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References updated October 2009 by date of publication, most recent first.
Behr, B., Rath,
D., Hildebrandt, T.B., Goeritz, F., Blottner, S., Portas, T.J., Bryant,
B.R., Sieg, B., Knieriem, A., de Graaf, S.P., Maxwell, W.M., Hermes, R.,
2009. Germany/Australia index of sperm sex sortability in elephants and
rhinoceros. Reprod. Domest. Anim 44, 273-277.
Abstract: Flow cytometric sexing of spermatozoa followed by application in
artificial insemination or in vitro fertilization provides a unique
opportunity to predetermine the sex of offspring and might enhance the
conservation management of endangered species in captivity such as the
elephant and rhinoceros. To obtain an indication of the sortability of
spermatozoa from these species, the relative DNA differences between X and
Y chromosome bearing spermatozoa (fresh, frozen thawed, epididymal) from
three rhinoceros species [white (Ceratotherium simum), black (Diceros
bicornis), Indian (Rhinoceros unicornis)] and both elephant species, the
Asian and the African elephant (Elephas maximus, Loxodonta Africana), were
determined through separation of spermatozoa into X and Y chromosome
bearing populations, using a modified high speed flow cytometer. The head
profile areas of spermatozoa from all five species were measured using
light microscopy. By multiplying the relative DNA differences and the head
profile areas, the sperm sorting indices were calculated to be 47, 48 and
51 for white, black and Indian rhinoceros respectively. The calculated
sorting index for the Asian elephant was 66. In the African elephant, we
determined the highest sorting index of 76. These results indicate the
practicability of flow cytometric sex sorting of spermatozoa from the
tested rhinoceros species and both elephant species. The lower sorting
indices in rhinos indicate that sex sorting of spermatozoa from the
rhinoceros will be more challenging than in elephants
Fulka, J., Jr.,
Loi, P., Ptak, G., Fulka, H., John, J.S., 2009. Hope for the mammoth?
Cloning Stem Cells 11, 1-4.
Garner, M.M.,
Helmick, K., Ochsenreiter, J., Richman, L.K., Latimer, E., Wise, A.G.,
Maes, R.K., Kiupel, M., Nordhausen, R.W., Zong, J.C., Hayward, G.S., 2009.
Clinico-pathologic features of fatal disease attributed to new variants of
endotheliotropic herpesviruses in two Asian elephants (Elephas maximus)
119. Vet. Pathol. 46, 97-104.
Abstract: The first herpesviruses described in association with serious
elephant disease were referred to as endotheliotropic herpesviruses (EEHV)
because of their ability to infect capillary endothelial cells and cause
potentially fatal disease. Two related viruses, EEHV1 and EEHV2, have been
described based on genetic composition. This report describes the
similarities and differences in clinicopathologic features of 2 cases of
fatal endotheliotropic herpesvirus infections in Asian elephants caused by
a previously unrecognized virus within the betaherpesvirus subfamily.
EEHV3 is markedly divergent from the 2 previously studied fatal
probosciviruses, based on polymerase chain reaction sequence analysis of 2
segments of the viral genome. In addition to ascites, widespread visceral
edema, petechiae, and capillary damage previously reported, important
findings with EEHV3 infection were the presence of grossly visible renal
medullary hemorrhage, a tropism for larger veins and arteries in various
tissues, relatively high density of renal herpetic inclusions, and
involvement of the retinal vessels. These findings indicate a less
selective organ tropism, and this may confer a higher degree of virulence
for EEHV3
Gobush, K.,
Kerr, B., Wasser, S., 2009. Genetic relatedness and disrupted social
structure in a poached population of African elephants
110. Mol. Ecol. 18, 722-734.
Abstract: We use genetic measures of relatedness and observations of
female bonding to examine the demographic signature of historically heavy
poaching of a population of free-ranging African elephants. We collected
dung samples to obtain DNA and observed behaviour from 102 elephant
families over a 25-month period in 2003-2005 in Mikumi National Park,
Tanzania. Poaching reduced the population by 75% in the decade prior to
the 1989 ivory trade ban; park records indicate that poaching dropped
significantly in Mikumi following the ban. Using 10 microsatellite loci,
DNA was genotyped in 203 elephants and pair-wise relatedness was
calculated among adult females within and between groups. The Mikumi
population is characterized by small group size, considerable variation in
group relatedness, females with no first-order adult relatives and females
that form only weak social bonds. We used gene-drop analysis and a model
of a genetically intact pedigree to compare our observed Mikumi group
relatedness to a simulated genetically intact unpoached expectation. The
majority of groups in Mikumi contain 2 to 3 adults; of these, 45% were
classified as genetically disrupted. Bonding, quantified with a pair-wise
association index, was significantly correlated with relatedness; however
only half of the females formed strong bonds with other females, and
relatedness was substantially lower for a given bond strength as compared
to an unpoached population. Female African elephants without kin
demonstrated considerable behavioural plasticity in this disturbed
environment, grouping with other females lacking kin, with established
groups, or remaining alone, unable to form any stable adult female-bonds.
We interpret these findings as the remaining effect of poaching
disturbance in Mikumi, despite a drop in the level of poaching since the
commercial trade in ivory was banned 15 years ago
Grus,
W.E., Zhang, J., 2009.
Origin of the
genetic components of the vomeronasal system in the common ancestor of all
extant vertebrates. Molecular Biology and Evolution 26, 407-419.
Abstract: Comparative genomics provides a valuable tool for inferring the
evolutionary history of physiological systems, particularly when this
information is difficult to ascertain by morphological traits. One such
example is the vomeronasal system (VNS), a vertebrate nasal chemosensory
system that is responsible for detecting intraspecific pheromonal cues as
well as environmental odorants. The morphological components of the VNS
are found only in tetrapods, but the genetic components of the system have
been found in teleost fish, in addition to tetrapods. To determine when
the genetic components of the VNS originated, we searched for the VNS-specific
genes in the genomes of two early diverging vertebrate lineages: the sea
lamprey from jawless fishes and the elephant shark from cartilaginous
fishes. Genes encoding vomeronasal type 1 receptors (V1Rs) and Trpc2, two
components of the vomeronasal signaling pathway, are present in the sea
lamprey genome, and both are expressed in the olfactory organ, revealing
that the genetic components of the present-day VNS existed in the common
ancestor of all extant vertebrates. Additionally, all three VNS genes,
Trpc2, V1Rs, and vomeronasal type 2 receptors (V2Rs), are found in the
elephant shark genome. Because V1Rs and V2Rs are related to two families
of taste receptors, we also searched the early diverging vertebrate
genomes for taste system genes and found them in the shark genome but not
in the lamprey. Coupled with known distributions of the genetic components
of the vertebrate main olfactory system, our results suggest staggered
origins of vertebrate sensory systems. These findings are important for
understanding the evolution of vertebrate sensory systems and illustrate
the utility of the genome sequences of early diverging vertebrates for
uncovering the evolution of vertebrate-specific traits
Hermes, R.,
Behr, B., Hildebrandt, T.B., Blottner, S., Sieg, B., Frenzel, A., Knieriem,
A., Saragusty, J., Rath, D., 2009. Sperm sex-sorting in the Asian elephant
(Elephas maximus). Anim Reprod. Sci. 112, 390-396.
Abstract: In captive Asian elephants, there is a strong need for
production of female offspring to enhance reproduction, counter premature
aging processes in female animals and reduce challenging management
situations derived from husbandry of several bulls in one institution.
Artificial insemination of flow cytometrically sex-sorted spermatozoa
offers the possibility to predetermine the sex of offspring with high
accuracy. The aims of this study were to determine a suitable semen
extender and basic parameters for flow cytometrical sex-sorting of Asian
elephant spermatozoa. In total 18 semen samples were collected by manual
rectal stimulation from one bull. Sperm quality parameters and sex
sortability of spermatozoa were evaluated after dilution in three semen
extenders (MES-HEPES-skim milk, MES-HEPES, TRIS-citric acid) and DNA
staining. MES-HEPES-skim milk was the only semen extender found suitable
to sex Asian elephant spermatozoa. From 18 ejaculates collected, 12 were
successfully sorted with a purity of 94.5+/-0.7% at an average sort rate
of 1945.5+/-187.5 spermatozoa per second. Sperm integrity, progressive and
total motility were 42.6+/-3.9%, 48.1+/-3.3%, 59.4+/-3.8% after DNA
labelling, and 64.8+/-3.2%, 58.0+/-5.0%, 70.8+/-4.4% after sorting,
respectively. After liquid storage of sorted spermatozoa for 12h at 4
degrees C, sperm integrity, progressive and total motility were
46.4+/-5.2%, 32.2+/-4.2% and 58.2+/-3.9%, respectively. The obtained
results provide a promising base to inseminate Asian elephants with sexed
semen
Landolfi, J.A.,
Schultz, S.A., Mikota, S.K., Terio, K.A., 2009. Development and validation
of cytokine quantitative, real time RT-PCR assays for characterization of
Asian elephant immune responses
71. Vet. Immunol. Immunopathol. 131, 73-78.
Abstract: Infectious disease is an important factor in Asian elephant
health and long-term species survival. In studying disease pathogenesis,
it is important to consider not only the pathogen, but also the
effectiveness of the host immune response. Currently, there is a paucity
of information available on elephant immune function. Measurement of
cytokine levels within clinical samples can provide valuable information
regarding immune function during health and disease that may elucidate
disease susceptibility. To develop tools for assessment of elephant immune
function, Asian elephant partial mRNA sequences for interleukin (IL)-2,
IL-4, IL-10, IL-12, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha,
transforming growth factor (TGF)-beta, glyceraldehyde 3-phosphate
dehydrogenase (GAPDH), and beta-actin were determined. Sequence
information was then utilized to design elephant-specific primers and
probes for quantitative, real time, RT-PCR assays for the measurement of
cytokine mRNA. Greater than 300bps of Asian elephant mRNA sequence were
determined for each cytokine of interest. Consistent and reproducible,
real time, RT-PCR assays with efficiencies of greater than 93% were also
developed. Assay sensitivities ranged from less than 1 to 5000 DNA copies
with the exception of IL-12, which had a sensitivity of 42,200 copies.
Employment of molecular techniques utilizing mRNA-based detection systems,
such as real time, RT-PCR, facilitate sensitive and specific cytokine
detection and measurement in samples from species for which commercial
reagents are not available. Future studies utilizing these techniques to
compare elephant immune function during health and in the face of
infection will be useful for characterizing the contribution of the
elephant immune system to disease
Lee, J.C.,
Hsieh, H.M., Huang, L.H., Kuo, Y.C., Wu, J.H., Chin, S.C., Lee, A.H.,
Linacre, A., Tsai, L.C., 2009. Ivory identification by DNA profiling of
cytochrome b gene. Int. J. Legal Med. 123, 117-121.
Abstract: Ivory can be visually identified in its native form as coming
from an elephant species; however, determining from which of the three
extant elephant species a section of ivory originates is more problematic.
We report on a method that will identify and distinguish the protected and
endangered elephant species, Elephas maximus or Loxodonta sp. To identify
the species of elephant from ivory products, we developed three groups of
nested PCR amplifications within the cytochrome b gene that generate
amplification products using highly degraded DNA isolated from confiscated
ivory samples dating from 1995. DNA from a total of 382 out of 453 ivory
samples were successfully isolated and amplified leading to species
identification. All sequences were searched against GenBank and found to
match with E. maximus and Loxodonta sp. with at least 99% similarity. The
samples that were tested came from eight Asian elephants, 14 African
forest elephants (Loxodonta cyclotis), and 360 African savannah elephants
(Loxodonta africana). This study demonstrates a high success rate in
species identification of ivory by a nested PCR approach within the
cytochrome b gene which provides the necessary information for the
protection of endangered species conservation
Lei, R.,
Brenneman, R.A., Schmitt, D.L., Louis, E.E., Jr., 2009. Detection of
Cytonuclear Genomic Dissociation in the North American Captive African
Elephant Collection. J. Hered.
Abstract: A total of 114 captive elephants (6 Asian; 108 African) from 43
private institutions or North American zoos accredited by the Association
of Zoos and Aquariums were sampled and evaluated to investigate genetic
status. Because previous analyses of the captive collection indicated
potential cytonuclear dissociation between mitochondrial DNA (mtDNA)
sequence and microsatellite nuclear DNA genotype data, we investigated
this phenomenon within the captive collection with 2 X-linked genes (BGN
and PHKA2) and 1 Y-linked gene (AMELY). These data reveal that individuals
with forest-derived elephant mtDNA lineages carried only savannah elephant
nuclear gene haplotypes. These results are concordant with a previous
study of wild populations sampled across Africa, indicating that
cytonuclear genomic dissociation was captured in the founders of the North
American African elephant collection. These results are important for
resolving questions that can potentially impact future management and
breeding programs related to the collection
Looringh van
Beeck, F.A., Reinink, P., Hermsen, R., Zajonc, D.M., Laven, M.J., Fun, A.,
Troskie, M., Schoemaker, N.J., Morar, D., Lenstra, J.A., Vervelde, L.,
Rutten, V.P., van, E.W., Van, R., I, 2009. Functional CD1d and/or NKT cell
invariant chain transcript in horse, pig, African elephant and guinea pig,
but not in ruminants
109. Mol. Immunol. 46, 1424-1431.
Abstract: CD1d-restricted invariant natural killer T cells (NKT cells)
have been well characterized in humans and mice, but it is unknown whether
they are present in other species. Here we describe the invariant TCR
alpha chain and the full length CD1d transcript of pig and horse.
Molecular modeling predicts that porcine (po) invariant TCR alpha
chain/poCD1d/alpha-GalCer and equine (eq) invariant TCR alpha
chain/eqCD1d/alpha-GalCer form complexes that are highly homologous to the
human complex. Since a prerequisite for the presence of NKT cells is the
expression of CD1d protein, we performed searches for CD1D genes and CD1d
transcripts in multiple species. Previously, cattle and guinea pig have
been suggested to lack CD1D genes. The CD1D genes of European taurine
cattle (Bos taurus) are known to be pseudogenes because of disrupting
mutations in the start codon and in the donor splice site of the first
intron. Here we show that the same mutations are found in six other
ruminants: African buffalo, sheep, bushbuck, bongo, N'Dama cattle, and roe
deer. In contrast, intact CD1d transcripts were found in guinea pig,
African elephant, horse, rabbit, and pig. Despite the discovery of a
highly homologous NKT/CD1d system in pig and horse, our data suggest that
functional CD1D and CD1d-restricted NKT cells are not universally present
in mammals
Murata, Y.,
Yonezawa, T., Kihara, I., Kashiwamura, T., Sugihara, Y., Nikaido, M.,
Okada, N., Endo, H., Hasegawa, M., 2009. Chronology of the extant African
elephant species and case study of the species identification of the small
African elephant with the molecular phylogenetic method
70. Gene 441, 176-186.
Abstract: Despite vigorous genetic studies of African elephants (Loxodonta
africana and L. cyclotis) during the last decade, their evolutionary
history is still obscure. Phylogenetic studies and coalescence time
estimation using longer nucleotide sequence data from denser samplings are
necessary to better understand the natural history of African elephants.
Further, species identification among African elephants is sometimes very
difficult using only the external morphological characteristics. This is a
serious problem for making an adequate breeding plan in zoological
gardens. In this paper, we investigated the continent-wide
phylogeographical pattern of the African elephants and estimated the
coalescence times among them. From these molecular data and geological
evidence, we proposed an evolutionary scenario for the African elephants.
We further demonstrated the effectiveness of molecular phylogenetic
methods in species identification.
Opazo, J.C.,
Sloan, A.M., Campbell, K.L., Storz, J.F., 2009. Origin and ascendancy of a
chimeric fusion gene: the beta/delta-globin gene of paenungulate mammals
84. Molecular Biology and Evolution 26, 1469-1478.
Abstract: The delta-globin gene (HBD) of eutherian mammals exhibits a
propensity for recombinational exchange with the closely linked beta-globin
gene (HBB) and has been independently converted by the HBB gene in
multiple lineages. Here we report the presence of a chimeric beta/delta
fusion gene in the African elephant (Loxodonta africana) that was created
by unequal crossing-over between misaligned HBD and HBB paralogs. The
recombinant chromosome that harbors the beta/delta fusion gene in
elephants is structurally similar to the "anti-Lepore" duplication mutant
of humans (the reciprocal exchange product of the hemoglobin Lepore
deletion mutant). However, the situation in the African elephant is unique
in that the chimeric beta/delta fusion gene supplanted the parental HBB
gene and is therefore solely responsible for synthesizing the beta-chain
subunits of adult hemoglobin. A phylogenetic survey of beta-like globin
genes in afrotherian and xenarthran mammals revealed that the origin of
the chimeric beta/delta fusion gene and the concomitant inactivation of
the HBB gene predated the radiation of "Paenungulata," a clade of
afrotherian mammals that includes three orders: Proboscidea (elephants),
Sirenia (dugongs and manatees), and Hyracoidea (hyraxes). The reduced
fitness of the human Hb Lepore deletion mutant helps to explain why
independently derived beta/delta fusion genes (which occur on an anti-Lepore
chromosome) have been fixed in a number of mammalian lineages, whereas the
reciprocal delta/beta fusion gene (which occurs on a Lepore chromosome)
has yet to be documented in any nonhuman mammal. This illustrates how the
evolutionary fates of chimeric fusion genes can be strongly influenced by
their recombinational mode of origin
Roca, A.L.,
Ishida, Y., Nikolaidis, N., Kolokotronis, S.O., Fratpietro, S., Stewardson,
K., Hensley, S., Tisdale, M., Boeskorov, G., Greenwood, A.D., 2009.
Genetic variation at hair length candidate genes in elephants and the
extinct woolly mammoth. BMC. Evol. Biol. 9, 232.
Abstract: BACKGROUND: Like humans, the living elephants are unusual among
mammals in being sparsely covered with hair. Relative to extant elephants,
the extinct woolly mammoth, Mammuthus primigenius, had a dense hair cover
and extremely long hair, which likely were adaptations to its subarctic
habitat. The fibroblast growth factor 5 (FGF5) gene affects hair length in
a diverse set of mammalian species. Mutations in FGF5 lead to recessive
long hair phenotypes in mice, dogs, and cats; and the gene has been
implicated in hair length variation in rabbits. Thus, FGF5 represents a
leading candidate gene for the phenotypic differences in hair length
notable between extant elephants and the woolly mammoth. We therefore
sequenced the three exons (except for the 3' UTR) and a portion of the
promoter of FGF5 from the living elephantid species (Asian, African
savanna and African forest elephants) and, using protocols for ancient
DNA, from a woolly mammoth. RESULTS: Between the extant elephants and the
mammoth, two single base substitutions were observed in FGF5, neither of
which alters the amino acid sequence. Modeling of the protein structure
suggests that the elephantid proteins fold similarly to the human FGF5
protein. Bioinformatics analyses and DNA sequencing of another locus that
has been implicated in hair cover in humans, type I hair keratin
pseudogene (KRTHAP1), also yielded negative results. Interestingly,
KRTHAP1 is a pseudogene in elephantids as in humans (although fully
functional in non-human primates). CONCLUSION: The data suggest that the
coding sequence of the FGF5 gene is not the critical determinant of hair
length differences among elephantids. The results are discussed in the
context of hairlessness among mammals and in terms of the potential impact
of large body size, subarctic conditions, and an aquatic ancestor on hair
cover in the Proboscidea
Rodriguez
Delgado, C.L., Waters, P.D., Gilbert, C., Robinson, T.J., Graves, J.A.,
2009. Physical mapping of the elephant X chromosome: conservation of gene
order over 105 million years. Chromosome. Res.
Abstract: All therian mammals (eutherians and marsupials) have an XX
female/XY male sex chromosome system or some variant of it. The X and Y
evolved from a homologous pair of autosomes over the 166 million years
since therian mammals diverged from monotremes. Comparing the sex
chromosomes of eutherians and marsupials defined an ancient X conserved
region that is shared between species of these mammalian clades. However,
the eutherian X (and the Y) was augmented by a recent addition (XAR) that
is autosomal in marsupials. XAR is part of the X in primates, rodents, and
artiodactyls (which belong to the eutherian clade Boreoeutheria), but it
is uncertain whether XAR is part of the X chromosome in more distantly
related eutherian mammals. Here we report on the gene content and order on
the X of the elephant (Loxodonta africana)-a representative of Afrotheria,
a basal endemic clade of African mammals-and compare these findings to
those of other documented eutherian species. A total of 17 genes were
mapped to the elephant X chromosome. Our results support the hypothesis
that the eutherian X and Y chromosomes were augmented by the addition of
autosomal material prior to eutherian radiation. Not only does the
elephant X bear the same suite of genes as other eutherian X chromosomes,
but gene order appears to have been maintained across 105 million years of
evolution, perhaps reflecting strong constraints posed by the eutherian X
inactivation system
Saragusty, J., Hildebrandt, T.B., Behr, B., Knieriem, A., Kruse, J.,
Hermes, R., 2009.
Successful
cryopreservation of Asian elephant (Elephas maximus) spermatozoa. Anim
Reprod. Sci. 115, 255-266.
Abstract: Reproduction in captive elephants is low and infant mortality is
high, collectively leading to possible population extinction. Artificial
insemination was developed a decade ago; however, it relies on
fresh-chilled semen from just a handful of bulls with inconsistent sperm
quality. Artificial insemination with frozen-thawed sperm has never been
described, probably, in part, due to low semen quality after
cryopreservation. The present study was designed with the aim of finding a
reliable semen freezing protocol. Screening tests included freezing semen
with varying concentrations of ethylene glycol, propylene glycol,
trehalose, dimethyl sulfoxide and glycerol as cryoprotectants and
assessing cushioned centrifugation, rapid chilling to suprazero
temperatures, freezing extender osmolarity, egg yolk concentration,
post-thaw dilution with cryoprotectant-free BC solution and the addition
of 10% (v/v) of autologous seminal plasma. The resulting optimal freezing
protocol uses cushioned centrifugation, two-step dilution with isothermal
285 m Osm/kg Berliner Cryomedium (BC) with final glycerol concentration of
7% and 16% egg yolk, and freezing in large volume by the directional
freezing technique. After thawing, samples are diluted 1:1 with BC
solution. Using this protocol, post-thaw evaluations results were:
motility upon thawing: 57.2+/-5.4%, motility following 30 min incubation
at 37 degrees C: 58.5+/-6.0% and following 3h incubation: 21.7+/-7.6%,
intact acrosome: 57.1+/-5.2%, normal morphology: 52.0+/-5.8% and
viability: 67.3+/-6.1%. With this protocol, good quality semen can be
accumulated for future use in artificial inseminations when and where
needed
Saragusty, J.,
Hermes, R., Goritz, F., Schmitt, D.L., Hildebrandt, T.B., 2009. Skewed
birth sex ratio and premature mortality in elephants. Anim Reprod. Sci.
115, 247-254.
Abstract: Sex allocation theories predict equal offspring number of both
sexes unless differential investment is required or some competition
exists. Left undisturbed, elephants reproduce well and in approximately
even numbers in the wild. We report an excess of males are born and
substantial juvenile mortality occurs, perinatally, in captivity. Studbook
data on captive births (CB, n=487) and premature deaths (PD, <5 years of
age; n=164) in Asian and African elephants in Europe and North America
were compared with data on Myanmar timber (Asian) elephants (CB, n=3070;
PD, n=738). Growth in CB was found in three of the captive populations. A
significant excess of male births occurred in European Asian elephants
(ratio: 0.61, P=0.044) and in births following artificial insemination
(0.83, P=0.003), and a numerical inclination in North American African
elephants (0.6). While juvenile mortality in European African and Myanmar
populations was 21-23%, it was almost double (40-45%) in all other captive
populations. In zoo populations, 68-91% of PD were within 1 month of birth
with stillbirth and infanticide being major causes. In Myanmar, 62% of
juvenile deaths were at >6 months with maternal insufficient milk
production, natural hazards and accidents being the main causes. European
Asian and Myanmar elephants PD was biased towards males (0.71, P=0.024 and
0.56, P<0.001, respectively). The skewed birth sex ratio and high juvenile
mortality hinder efforts to help captive populations become
self-sustaining. Efforts should be invested to identify the mechanism
behind these trends and seek solutions for them.
Schwarz, C.,
Debruyne, R., Kuch, M., McNally, E., Schwarcz, H., Aubrey, A.D., Bada, J.,
Poinar, H., 2009. New insights from old bones: DNA preservation and
degradation in permafrost preserved mammoth remains
89. Nucleic Acids Res. 37, 3215-3229.
Abstract: Despite being plagued by heavily degraded DNA in
palaeontological remains, most studies addressing the state of DNA
degradation have been limited to types of damage which do not pose a
hindrance to Taq polymerase during PCR. Application of serial qPCR to the
two fractions obtained during extraction (demineralization and protein
digest) from six permafrost mammoth bones and one partially degraded
modern elephant bone has enabled further insight into the changes which
endogenous DNA is subjected to during diagenesis. We show here that both
fractions exhibit individual qualities in terms of the prevailing type of
DNA (i.e. mitochondrial versus nuclear DNA) as well as the extent of
damage, and in addition observed a highly variable ratio of mitochondrial
to nuclear DNA among the six mammoth samples. While there is evidence
suggesting that mitochondrial DNA is better preserved than nuclear DNA in
ancient permafrost samples, we find the initial DNA concentration in the
bone tissue to be as relevant for the total accessible mitochondrial DNA
as the extent of DNA degradation post-mortem. We also evaluate the general
applicability of indirect measures of preservation such as amino-acid
racemization, bone crystallinity index and thermal age to these
exceptionally well-preserved samples
Schwarz, C.,
Debruyne, R., Kuch, M., McNally, E., Schwarcz, H., Aubrey, A.D., Bada, J.,
Poinar, H., 2009.
New
insights from old bones: DNA preservation and degradation in permafrost
preserved mammoth remains.
Nucleic Acids Res March 24.
Sherwood, C.C.,
Stimpson, C.D., Butti, C., Bonar, C.J., Newton, A.L., Allman, J.M., Hof,
P.R., 2009. Neocortical neuron types in Xenarthra and Afrotheria:
implications for brain evolution in mammals. Brain Struct. Funct. 213,
301-328.
Abstract: Interpreting the evolution of neuronal types in the cerebral
cortex of mammals requires information from a diversity of species.
However, there is currently a paucity of data from the Xenarthra and
Afrotheria, two major phylogenetic groups that diverged close to the base
of the eutherian mammal adaptive radiation. In this study, we used
immunohistochemistry to examine the distribution and morphology of
neocortical neurons stained for nonphosphorylated neurofilament protein,
calbindin, calretinin, parvalbumin, and neuropeptide Y in three xenarthran
species-the giant anteater (Myrmecophaga tridactyla), the lesser anteater
(Tamandua tetradactyla), and the two-toed sloth (Choloepus didactylus)-and
two afrotherian species-the rock hyrax (Procavia capensis) and the black
and rufous giant elephant shrew (Rhynchocyon petersi). We also studied the
distribution and morphology of astrocytes using glial fibrillary acidic
protein as a marker. In all of these species, nonphosphorylated
neurofilament protein-immunoreactive neurons predominated in layer V.
These neurons exhibited diverse morphologies with regional variation.
Specifically, high proportions of atypical neurofilament-enriched neuron
classes were observed, including extraverted neurons, inverted pyramidal
neurons, fusiform neurons, and other multipolar types. In addition, many
projection neurons in layers II-III were found to contain calbindin. Among
interneurons, parvalbumin- and calbindin-expressing cells were generally
denser compared to calretinin-immunoreactive cells. We traced the
evolution of certain cortical architectural traits using phylogenetic
analysis. Based on our reconstruction of character evolution, we found
that the living xenarthrans and afrotherians show many similarities to the
stem eutherian mammal, whereas other eutherian lineages display a greater
number of derived traits
Thongtip, N.,
Mahasawangkul, S., Thitaram, C., Pongsopavijitr, P., Kornkaewrat, K.,
Pinyopummin, A., Angkawanish, T., Jansittiwate, S., Rungsri, R.,
Boonprasert, K., Wongkalasin, W., Homkong, P., Dejchaisri, S., Wajjwalku,
W., Saikhun, K., 2009. Successful artificial insemination in the Asian
elephant (Elephas maximus) using chilled and frozen-thawed semen. Reprod.
Biol. Endocrinol. 7, 75.
Abstract: BACKGROUND: Artificial insemination (AI) using frozen-thawed
semen is well established and routinely used for breeding in various
mammalian species. However, there is no report of the birth of elephant
calves following AI with frozen-thawed semen. The objective of the present
study was to investigate the fertilizing ability of chilled and
frozen-thawed semen in the Asian elephant following artificial
insemination (AI). METHODS: Semen samples were collected by from 8 bulls
(age range, 12-to 42-years) by manual stimulation. Semen with high quality
were either cooled to 4 degrees C or frozen in liquid nitrogen (-196
degrees C) before being used for AI. Blood samples collected from ten
elephant females (age range, 12-to 52-years) were assessed for estrus
cycle and elephants with normal cycling were used for AI. Artificial
insemination series were conducted during 2003 to 2008; 55 and 2 AI trials
were conducted using frozen-thawed and chilled semen, respectively.
Pregnancy was detected using transrectal ultrasonography and serum
progestagen measurement. RESULTS: One female (Khod) inseminated with
chilled semen became pregnant and gave birth in 2007. The gestation length
was 663 days and the sex of the elephant calf was male. One female (Sao)
inseminated with frozen-thawed semen showed signs of pregnancy by
increasing progestagen levels and a fetus was observed for 5 months by
transrectal ultrasonography. CONCLUSION: This is the first report showing
pregnancy following AI with frozen-thawed semen in the Asian elephant.
Successful AI in the Asian elephant using either chilled or frozen-thawed
semen is a stepping stone towards applying this technology for genetic
improvement of the elephant population.
Vidya, T.N., Sukumar, R., Melnick, D.J., 2009.
Range-wide
mtDNA phylogeography yields insights into the origins of Asian elephants.
Proc. Biol. Sci. 276, 893-902.
Abstract: Recent phylogeographic studies of the endangered Asian elephant
(Elephas maximus) reveal two highly divergent mitochondrial DNA (mtDNA)
lineages, an elucidation of which is central to understanding the
species's evolution. Previous explanations for the divergent clades
include introgression of mtDNA haplotypes between ancestral species,
allopatric divergence of the clades between Sri Lanka or the Sunda region
and the mainland, historical trade of elephants, and retention of
divergent lineages due to large population sizes. However, these studies
lacked data from India and Myanmar, which host approximately 70 per cent
of all extant Asian elephants. In this paper, we analyse mtDNA sequence
data from 534 Asian elephants across the species's range to explain the
current distribution of the two divergent clades. Based on phylogenetic
reconstructions, estimates of times of origin of clades, probable
ancestral areas of origin inferred from dispersal-vicariance analyses and
the available fossil record, we believe both clades originated from
Elephas hysudricus. This probably occurred allopatrically in different
glacial refugia, the alpha clade in the Myanmar region and the beta clade
possibly in southern India-Sri Lanka, 1.6-2.1Myr ago. Results from nested
clade and dispersal-vicariance analyses indicate a subsequent isolation
and independent diversification of the beta clade in both Sri Lanka and
the Sunda region, followed by northward expansion of the clade. We also
find more recent population expansions in both clades based on mismatch
distributions. We therefore suggest a contraction-expansion scenario
during severe climatic oscillations of the Quaternary, with range
expansions from different refugia during warmer interglacials leading to
the varying geographical overlaps of the two mtDNA clades. We also
demonstrate that trade in Asian elephants has not substantially altered
the species's mtDNA population genetic structure
Wallis, M.,
2009. Prolactin in the Afrotheria: characterization of genes encoding
prolactin in elephant (Loxodonta africana), hyrax (Procavia capensis) and
tenrec (Echinops telfairi). J. Endocrinol. 200, 233-240.
Abstract: Pituitary prolactin shows an episodic pattern of molecular
evolution, with occasional short bursts of rapid change imposed on a
generally rather slow evolutionary rate. In mammals, episodes of rapid
change occurred in the evolution of primates, cetartiodactyls, rodents and
the elephant. The bursts of rapid evolution in cetartiodactyls and rodents
were followed by duplications of the prolactin gene that gave rise to
large families of prolactin-related proteins including placental lactogens,
while in primates the burst was followed by corresponding duplications of
the related GH gene. The position in elephant is less clear. Extensive
data relating to the genomic sequences of elephant and two additional
members of the group Afrotheria are now available, and have been used here
to characterize the prolactin genes in these species and explore whether
additional prolactin-related genes are present. The results confirm the
rapid evolution of elephant (Loxodonta africana) prolactin - the sequence
of elephant prolactin is substantially different from that predicted for
the ancestral placental mammal. Hyrax (Procavia capensis) prolactin is
even more divergent but tenrec (Echinops telfairi) prolactin is strongly
conserved. No evidence was obtained from searches of public databases for
additional genes encoding prolactin-like proteins in any of these species.
Detailed analysis of evolutionary rates, and other factors, indicates that
the episode of rapid change in hyrax, and probably elephant, was adaptive,
though the nature of the associated biological change(s) is not clear
Wasser, S.K.,
Clark, B., Laurie, C., 2009. The ivory trail
42. Scientific American 301, 68-74, 76.
Wittemyer, G.,
Okello, J.B., Rasmussen, H.B., Arctander, P., Nyakaana, S.,
Douglas-Hamilton, I., Siegismund, H.R., 2009. Where sociality and
relatedness diverge: the genetic basis for hierarchical social
organization in African elephants. Proc Royal Soc Biol 276,
3513-3521.
Abstract: Hierarchical properties characterize elephant fission-fusion
social organization whereby stable groups of individuals coalesce into
higher order groups or split in a predictable manner. This hierarchical
complexity is rare among animals and, as such, an examination of the
factors driving its emergence offers unique insight into the evolution of
social behaviour. Investigation of the genetic basis for such social
affiliation demonstrates that while the majority of core social groups
(second-tier affiliates) are significantly related, this is not
exclusively the case. As such, direct benefits received through membership
of these groups appear to be salient to their formation and maintenance.
Further analysis revealed that the majority of groups in the two higher
social echelons (third and fourth tiers) are typically not significantly
related. The majority of third-tier members are matrilocal, carrying the
same mtDNA control region haplotype, while matrilocality among fourth-tier
groups was slightly less than expected at random. Comparison of results to
those from a less disturbed population suggests that human depredation,
leading to social disruption, altered the genetic underpinning of social
relations in the study population. These results suggest that inclusive
fitness benefits may crystallize elephant hierarchical social structuring
along genetic lines when populations are undisturbed. However, indirect
benefits are not critical to the formation and maintenance of second-,
third- or fourth-tier level bonds, indicating the importance of direct
benefits in the emergence of complex, hierarchical social relations among
elephants. Future directions and conservation implications are discussed
Wong, K., 2009.
Decoding the mammoth
108. Scientific American 300, 26-27.
Archie, E.A.,
Maldonado, J.E., Hollister-Smith, J.A., Poole, J.H., Moss, C.J.,
Fleischer, R.C., Alberts, S.C., 2008. Fine-scale population genetic
structure in a fission-fusion society. Mol. Ecol. 17, 2666-2679.
Abstract: Nonrandom patterns of mating and dispersal create fine-scale
genetic structure in natural populations - especially of social mammals -
with important evolutionary and conservation genetic consequences. Such
structure is well-characterized for typical mammalian societies; that is,
societies where social group composition is stable, dispersal is
male-biased, and males form permanent breeding associations in just one or
a few social groups over the course of their lives. However, genetic
structure is not well understood for social mammals that differ from this
pattern, including elephants. In elephant societies, social groups fission
and fuse, and males never form permanent breeding associations with female
groups. Here, we combine 33 years of behavioural observations with genetic
information for 545 African elephants (Loxodonta africana), to investigate
how mating and dispersal behaviours structure genetic variation between
social groups and across age classes. We found that, like most social
mammals, female matrilocality in elephants creates co-ancestry within core
social groups and significant genetic differentiation between groups (Phi(ST)
= 0.058). However, unlike typical social mammals, male elephants do not
bias reproduction towards a limited subset of social groups, and instead
breed randomly across the population. As a result, reproductively dominant
males mediate gene flow between core groups, which creates cohorts of
similar-aged paternal relatives across the population. Because poaching
tends to eliminate the oldest elephants from populations, illegal hunting
and poaching are likely to erode fine-scale genetic structure. We discuss
our results and their evolutionary and conservation genetic implications
in the context of other social mammals
Baker, C.S.,
2008. A truer measure of the market: the molecular ecology of fisheries
and wildlife trade. Mol. Ecol. 17, 3985-3998.
Abstract: Wildlife and fisheries markets are end-points in the supply
chain of both legitimate and illegitimate or unregulated trade in species
and natural products. Molecular ecology provides powerful tools for
surveillance and estimation of this trade. Here, I review the application
of these tools to market surveys and species in trade, including species
identification and molecular taxonomy, population assignment and
'mixed-stock' analysis, genetic tracking and capture-recapture by
individual identification. I consider the analogy of markets to natural
populations and also the unique features that require novel analytical
approaches and sampling design. In the most developed of these
applications, the molecular ecology of market surveys and confiscated
trade shipments has provided independent estimates of illegal, unregulated
or unreported exploitation for sharks, elephants and whales. Although each
study has taken advantage of information from trade records or official
government reports concerning the ostensible levels of exploitation, it is
telling that the truer measure of exploitation seems to arise from the
market end-point of the supply chain
Bechert, U.,
Southern, S., Chase, M.
Minimally invasive molecular health analysis in elephants.
Proc American Associaton of Zoo Veterinarians and Assoc of Reptile and
Amphibian Veterinarians. 88. 2008. 11-10-2008.
Ref Type: Conference Proceeding
Abstract:
This
paper describes the application of a new assay platform called Stress
Response Profiling (SRP) to the analysis of health status in elephants.
SRP assays use a large biomarker panel as an indicator of chronically
perturbed physiologic homeostasis ("chronic stress"),1,2 which is a known
predictor of increased morbidity, infertility and mortality rates.3-8 SRP
assays have a broad-based sensitivity to diverse types of stressors in
multiple species of vertebrates.2 A minimally invasive SRP assay is based
on skin microsamples obtained using routine biopsy procedures.9 The skin
SRP assay was applied to captive African elephants with clinically
diagnosed gastrointestinal infections and to healthy wild elephants.10 The
elephant health status was classified using a reference database of SR
biomarker profiles corresponding to eight species of normal and stressed
animals. The biomarker profiles were converted into pathway profiles
indicating that the molecular mechanism of the elephant gastrointestinal
infections preferentially involved responses to misfolded proteins and DNA
lesions. To rapidly and economically screen samples from 70 free-ranging
African elephants sampled in Northern Botswana, we used a multiplexed SRP
assay called multi-SRP.1,2 Statistical analysis of the multi-SRP scores
showed correlations with population density, movements, and human-elephant
conflict reports. In
summary, this paper documents that SRP and multi-SRP assays are suitable
for the elephant skin and relevant to both symptomatic diseases and
asymptomatic effects of environmental and anthropogenic stressors. We
anticipate that the SRP technology might have a wide range of potential
applications in veterinary medicine and ecosystem conservation.
LITERATURE CITED
1. Southern, S.O., A.C. Allen, and N. Kellar. 2002. Molecular
signature of physiological stress in dolphins based on protein expression
profiling of skin. Administrative Report LJ-02-27, National Marine
Fisheries Service, SW Fisheries Science Center, La Jolla, California.
2. Southern, S.O., and G.W. Lilienthal. 2008. New technology for early
detection of health threats. Proc. SPIE 69450F.
3. Camougrand, N., and M. Rigoulet. 2001. Aging and oxidative stress:
studies of some genes involved both in aging and in response to oxidative
stress. Respir. Physiol. 128:393-40.
4. Epel, E.S., J. Lin, F.H. Wilhelm, O.M. Wolkowitz, R. Cawthon, N.E.
Adler, C. Dolbier, W.B. Mendes, and E.H. Blackburn. 2006. Cell aging in
relation to stress arousal and cardiovascular disease risk factors.
Psychoneuroendocrinology. 31:277-87.
5. Feder, M.E., and G.E. Hofmann. 1999. Heat-shock proteins, molecular
chaperones, and the stress response: evolutionary and ecological
physiology. Ann. Rev. Physiol. 61:243-82.
6. Kapahi, P., M.E. Boulton, and T.B.L. Kirkwood. 1999. Positive
correlation between mammalian life span and cellular resistance to stress.
Free Radical Biol. Med. 26:495-500.
7. Selye, H.A. 1936. Syndrome produced by diverse nocuous agents. Nature
138:32.
8. Wilson, J.F., and E.J. Kopitzke 2002. Stress and infertility Curr.
Womens Health Rep. 2: 194
Gilbert, C.,
Pace, J.K., Waters, P.D., 2008. Target site analysis of RTE1_LA and its
AfroSINE partner in the elephant genome. Gene 425 , 1-8.
Abstract: SINEs retrotranspose using their partner LINE's enzymatic
machinery. It has recently been proposed that AfroSINEs ending with GGTTT
3' tandem repeats were mobilized by RTE elements ending with CAA 3' tandem
repeats in the Afrotherian genome. Using sequences from the elephant
genome, we show that AfroSINEs derive from RTE ending with GGTTT-like 3'
tandem repeats, a subgroup of RTE1_LA that only reached low copy number,
and confirm that they were most likely mobilized by RTE ending with CAA(n)
tandem repeats (RTE1_LA-CAA(n)). This partnership is supported by sequence
similarity between two regions of the elements, overlap in the timing of
their activity, common features of their target site consensus that are
not shared by other members of the RTE family, and their high copy number.
Detailed analyses of pre-insertion loci reveal that like many other
apurinic/apyrimidinic endonuclease encoding elements, RTE1_LA-CAA(n) shows
loose target site specificity. In addition, the RTE1_LA-CAA(n) target site
consensus shares several structural and primary sequence features with
that of LINE1, suggesting that these two elements share close functional
similarity in the target primed reverse transcription (TPRT) reaction.
Interestingly, although globally similar, the target site consensus of
AfroSINE(Anc) and RTE1_LA-CAA(n) differ in several aspects. These
differences, not observed among all SINE/LINE pairs so far examined, are
most likely due to the fact that AfroSINEs and RTE1_LA-CAA(n) are
terminated by a different tandem repeat motif. We propose that these
differences reflect constraints imposed by base pairing interactions
between the mRNA 3' terminal tandem repeats and the target DNA at the
onset of TPRT. So in addition to the endonuclease nicking preference, the
mRNA of these elements appears to play an important role in integration
site choice through a passive, post-nicking, selective process
Gilbert, M.T.,
Drautz, D.I., Lesk, A.M., Ho, S.Y., Qi, J., Ratan, A., Hsu, C.H., Sher,
A., Dalen, L., Gotherstrom, A., Tomsho, L.P., Rendulic, S., Packard, M.,
Campos, P.F., Kuznetsova, T.V., Shidlovskiy, F., Tikhonov, A., Willerslev,
E., Iacumin, P., Buigues, B., Ericson, P.G., Germonpre, M., Kosintsev, P.,
Nikolaev, V., Nowak-Kemp, M., Knight, J.R., Irzyk, G.P., Perbost, C.S.,
Fredrikson, K.M., Harkins, T.T., Sheridan, S., Miller, W., Schuster, S.C.,
2008. Intraspecific phylogenetic analysis of Siberian woolly mammoths
using complete mitochondrial genomes. Proc. Natl. Acad. Sci. U. S. A 105,
8327-8332.
Abstract: We report five new complete mitochondrial DNA (mtDNA) genomes of
Siberian woolly mammoth (Mammuthus primigenius), sequenced with up to
73-fold coverage from DNA extracted from hair shaft material. Three of the
sequences present the first complete mtDNA genomes of mammoth clade II.
Analysis of these and 13 recently published mtDNA genomes demonstrates the
existence of two apparently sympatric mtDNA clades that exhibit high
interclade divergence. The analytical power afforded by the analysis of
the complete mtDNA genomes reveals a surprisingly ancient coalescence age
of the two clades, approximately 1-2 million years, depending on the
calibration technique. Furthermore, statistical analysis of the temporal
distribution of the (14)C ages of these and previously identified members
of the two mammoth clades suggests that clade II went extinct before clade
I. Modeling of protein structures failed to indicate any important
functional difference between genomes belonging to the two clades,
suggesting that the loss of clade II more likely is due to genetic drift
than a selective sweep
Gobush, K.S.,
Mutayoba, B.M., Wasser, S.K., 2008. Long-term impacts of poaching on
relatedness, stress physiology, and reproductive output of adult female
african elephants. Conserv. Biol. 22, 1590-1599.
Abstract: Widespread poaching prior to the 1989 ivory ban greatly altered
the demographic structure of matrilineal African elephant (Loxodonta
africana) family groups in many populations by decreasing the number of
old, adult females. We assessed the long-term impacts of poaching by
investigating genetic, physiological, and reproductive correlates of a
disturbed social structure resulting from heavy poaching of an African
elephant population in Mikumi National Park, Tanzania, prior to 1989. We
examined fecal glucocorticoid levels and reproductive output among 218
adult female elephants from 109 groups differing in size, age structure,
and average genetic relatedness over 25 months from 2003 to 2005. The
distribution in group size has changed little since 1989, but the number
of families with tusked old matriarchs has increased by 14.2%. Females
from groups that lacked an old matriarch, first-order adult relatives, and
strong social bonds had significantly higher fecal glucocorticoid values
than those from groups with these features (all females R(2)= 0.31;
females in multiadult groups R(2)= 0.46). Females that frequented isolated
areas with historically high poaching risk had higher fecal glucocorticoid
values than those in low poaching risk areas. Females with weak bonds and
low group relatedness had significantly lower reproductive output
(R(2)[U]=0.21). Females from disrupted groups, defined as having observed
average group relatedness 1 SD below the expected mean for a simulated
unpoached family, had significantly lower reproductive output than females
from intact groups, despite many being in their reproductive prime. These
results suggest that long-term negative impacts from poaching of old,
related matriarchs have persisted among adult female elephants 1.5 decades
after the 1989 ivory ban was implemented
Hofreiter, M.,
2008. DNA sequencing: Mammoth genomics. Nature 456, 330-331.
Huang, S.,
2008. Ancient fossil specimens of extinct species are genetically more
distant to an outgroup than extant sister species are. Riv. Biol. 101,
93-108.
Abstract: There exists a remarkable correlation between genetic distance
as measured by protein or DNA dissimilarity and time of species divergence
as inferred from fossil records. This observation has provoked the
molecular clock hypothesis. However, data inconsistent with the hypothesis
have steadily accumulated in recent years from studies of extant
organisms. Here the published DNA and protein sequences from ancient
fossil specimens were examined to see if they would support the molecular
clock hypothesis. The hypothesis predicts that ancient specimens cannot be
genetically more distant to an outgroup than extant sister species are.
Also, two distinct ancient specimens cannot be genetically more distant
than their extant sister species are. The findings here do not conform to
these predictions. Neanderthals are more distant to chimpanzees and
gorillas than modern humans are. Dinosaurs are more distant to frogs than
extant birds are. Mastodons are more distant to opossums than other
placental mammals are. The genetic distance between dinosaurs and
mastodons is greater than that between extant birds and mammals.
Therefore, while the molecular clock hypothesis is consistent with some
data from extant organisms, it has yet to find support from ancient
fossils. Far more damaging to the hypothesis than data from extant
organisms, which merely question the constancy of mutation rate, the study
of ancient fossil organisms here challenges for the first time the
fundamental premise of modern evolution theory that genetic distances had
always increased with time in the past history of life on Earth
Jackson, T.,
van Aarde, R., 2008. CSI:Africa. Africa Geographic 16, 35-39.
Abstract: In 1989, prompted by the wholesale slaughter of elephants for
their tusks, CITES (the Convention on International Trade in Endangered
Species) implemented a worldwide ban on the trade in ivory. Nearly 20
years later, elephant populations in some parts of Africa have stabilised,
some are even increasing, and yet, seizures of ivory destined for the
black market continue. While imposing tougher punishments on poachers,
middlemen and dealers is an obvious measure, first prize would be
preventing the elephants from being killed in the first place. To do this
effectively, however, you need to know which populations are at risk. So,
how can we find out where all the ivory is coming from? The answers, Tim
Jackson finds, range from the seemingly low-tech collection of elephant
dung to the very latest developments in DNA analysis.
Konnai, S.,
Mekata, H., Odbileg, R., Simuunza, M., Chembensof, M., Witola, W.H., Tembo,
M.E., Chitambo, H., Inoue, N., Onuma, M., Ohashi, K., 2008. Detection of
Trypanosoma brucei in field-captured tsetse flies and identification of
host species fed on by the infected flies. Vector. Borne. Zoonotic. Dis. 8,
565-573.
Abstract: The prevalence of trypanosome infections in tsetse flies in the
Chiawa area of Lower Zambezi in Zambia, with endemic trypanosomosis, was
determined by a polymerase chain reaction (PCR) method that allowed the
detection of trypanosome DNA and determination of the type of animal host
fed on by the tsetse fly Glossina pallidipes, using tsetse-derived DNA
extracts as templates. Ninety G. pallidipes (82 females and 8 males;
18.3%) of the 492 flies captured by baited biconical traps tested positive
for the presence of Trypanosoma brucei species genomic DNA. Of the 90 T.
brucei-positive flies, 47 (52.2%) also tested positive for vertebrate
mitochondrial DNA. Sequence analysis of the vertebrate mitochondrial DNA
amplicons established that they originated from 8 different vertebrate
species, namely, human (Homo sapiens), African elephant (Loxodonta
cyclotis), African buffalo (Syncerus caffer), waterbuck (Kobus
ellipsiprymnus), roan antelope (Hippotragus equinus), greater kudu
(Tragelaphus strepsiceros), warthog (Phacochoerus africanus), and goat
(Capra hircus). Furthermore, to investigate the prevalence of trypanosome
infections in domestic goats in the same area where trypanosomes had been
detected in tsetse files, a total of 86 goats were randomly selected from
6 different herds. Among the selected goats, 36 (41.9%) were found to be
positive for T. brucei species. This combined detection method would be an
ideal approach not only for mass screening for infection prevalence in
tsetse populations, but also for the prediction of natural reservoirs in
areas endemic for trypanosomosis
Kurth, A.,
Wibbelt, G., Gerber, H.P., Petschaelis, A., Pauli, G., Nitsche, A., 2008.
Rat-to-elephant-to-human transmission of cowpox virus. Emerg. Infect. Dis.
14, 670-671.
Liu, A.G.,
Seiffert, E.R., Simons, E.L., 2008. Stable isotope evidence for an
amphibious phase in early proboscidean evolution. Proc. Natl. Acad. Sci.
U. S. A 105, 5786-5791.
Abstract: The order Proboscidea includes extant elephants and their
extinct relatives and is closely related to the aquatic sirenians
(manatees and dugongs) and terrestrial hyracoids (hyraxes). Some analyses
of embryological, morphological, and paleontological data suggest that
proboscideans and sirenians shared an aquatic or semiaquatic common
ancestor, but independent tests of this hypothesis have proven elusive.
Here we test the hypothesis of an aquatic ancestry for advanced
proboscideans by measuring delta(18)O in tooth enamel of two late Eocene
proboscidean genera, Barytherium and Moeritherium, which are sister taxa
of Oligocene-to-Recent proboscideans. The combination of low delta(18)O
values and low delta(18)O standard deviations in Barytherium and
Moeritherium matches the isotopic pattern seen in aquatic and semiaquatic
mammals, and differs from that of terrestrial mammals. delta(13)C values
of these early proboscideans suggest that both genera are likely to have
consumed freshwater plants, although a component of C(3) terrestrial
vegetation cannot be ruled out. The simplest explanation for the combined
evidence from isotopes, dental functional morphology, and depositional
environments is that Barytherium and Moeritherium were at least
semiaquatic and lived in freshwater swamp or riverine environments, where
they grazed on freshwater vegetation. These results lend new support to
the hypothesis that Oligocene-to-Recent proboscideans are derived from
amphibious ancestors
Lotfy, W.M.,
Brant, S.V., DeJong, R.J., Le, T.H., Demiaszkiewicz, A., Rajapakse, R.P.,
Perera, V.B., Laursen, J.R., Loker, E.S., 2008. Evolutionary origins,
diversification, and biogeography of liver flukes (Digenea, Fasciolidae).
American Journal of Tropical Medicine and Hygiene 79, 248-255.
Abstract: Fasciolid flukes are among the largest and best known digenetic
trematodes and have considerable historical and veterinary significance.
Fasciola hepatica is commonly implicated in causing disease in humans. The
origins, patterns of diversification, and biogeography of fasciolids are
all poorly known. We have undertaken a molecular phylogenetic study using
28S, internal transcribed spacer 1 and 2 (ITS-1 and ITS-2) of nuclear
ribosomal DNA, and mitochondrial nicotinamide dehydrogenase subunit 1
(nad1) that included seven of the nine recognized species in the family.
The fasciolids examined comprise a monophyletic group with the most basal
species recovered from African elephants. We hypothesize fasciolids
migrated from Africa to Eurasia, with secondary colonization of Africa.
Fasciolids have been conservative in maintaining relatively large adult
body size, but anatomical features of their digestive and reproductive
systems are available. These flukes have been opportunistic, with respect
to switching to new snail (planorbid to lymnaeid) and mammalian hosts and
from intestinal to hepatic habitats within mammals
Lynch, V.J.,
Tanzer, A., Wang, Y., Leung, F.C., Gellersen, B., Emera, D., Wagner, G.P.,
2008. Adaptive changes in the transcription factor HoxA-11 are essential
for the evolution of pregnancy in mammals. Proc. Natl. Acad. Sci. U. S. A
105, 14928-14933.
Abstract: Evolutionary change in gene regulation can result from changes
in cis-regulatory elements, leading to differences in the temporal and
spatial expression of genes or in the coding region of transcription
factors leading to novel functions or both. Although there is a growing
body of evidence supporting the importance of cis-regulatory evolution,
examples of protein-mediated evolution of novel developmental pathways
have not been demonstrated. Here, we investigate the evolution of
prolactin (PRL) expression in endometrial cells, which is essential for
placentation/pregnancy in eutherian mammals and is a direct regulatory
target of the transcription factor HoxA-11. Here, we show that (i)
endometrial PRL expression is a derived feature of placental mammals, (ii)
the PRL regulatory gene HoxA-11 experienced a period of strong positive
selection in the stem-lineage of eutherian mammals, and (iii) only HoxA-11
proteins from placental mammals, including the reconstructed ancestral
eutherian gene, are able to up-regulate PRL from the promoter used in
endometrial cells. In contrast, HoxA-11 from the reconstructed therian
ancestor, opossum, platypus, and chicken are unable to up-regulate PRL
expression. These results demonstrate that the evolution of novel gene
expression domains is not only mediated by the evolution of cis-regulatory
elements but can also require evolutionary changes of transcription factor
proteins themselves
Mekata, H.,
Konnai, S., Simuunza, M., Chembensofu, M., Kano, R., Witola, W.H., Tembo,
M.E., Chitambo, H., Inoue, N., Onuma, M., Ohashi, K., 2008. Prevalence and
source of trypanosome infections in field-captured vector flies (Glossina
pallidipes) in southeastern Zambia. J. Vet. Med. Sci. 70, 923-928.
Abstract: The prevalence of trypanosome infections in tsetse flies,
Glossina pallidipes, collected from Chiawa and Chakwenga in Zambia with
endemic trypanosomosis was assessed by polymerase chain reaction (PCR).
Out of the 550 G. pallidipes, 58 (10.5%) flies were found to harbor
trypanosome DNA. Infection rates of tsetse with Trypanosoma vivax
universal, Trypanosoma congolense savannah, T. congolense forest and T.
congolense kilifi were 4.2% (23/550), 4.7% (26/550), 1.1% (6/550) and 1.6%
(9/550), respectively. To determine the mammalian hosts of T. congolense
and T. vivax infections from the tsetse flies, mammalian mitochondrion DNA
of blood meal in these flies were analyzed by PCR and subsequent gene
sequence analysis of the amplicons. Sequence analysis showed the presence
of cytochrome b gene (cyt b) of 7 different mammalian species such as
human, elephant, buffalo, goat, warthog, greater kudu and cattle. Goats
which were main livestock in these areas were further examined to know the
extent of its contribution in spreading the infection. We examined the
prevalence of trypanosome infections in the domestic goat population in 6
settlements in Chiawa alone. Of the 86 goats sampled, 4 (4.6%), 5 (5.8%),
4 (4.6%) and 4 (4.6%) were positive for T. vivax universal, T. congolense
savannah, forest and kilifi, respectively. These findings showed that the
host-source of trypanosome infections in vector fly give a vital
information about spread of infection. The result of this study will
certainly contribute in elucidating more the epidemiology of
trypanosomosis
Miller, W.,
Drautz, D.I., Ratan, A., Pusey, B., Qi, J., Lesk, A.M., Tomsho, L.P.,
Packard, M.D., Zhao, F., Sher, A., Tikhonov, A., Raney, B., Patterson, N.,
Lindblad-Toh, K., Lander, E.S., Knight, J.R., Irzyk, G.P., Fredrikson, K.M.,
Harkins, T.T., Sheridan, S., Pringle, T., Schuster, S.C., 2008. Sequencing
the nuclear genome of the extinct woolly mammoth. Nature 456,
387-390.
Abstract: In 1994, two independent groups extracted DNA from several
Pleistocene epoch mammoths and noted differences among individual
specimens. Subsequently, DNA sequences have been published for a number of
extinct species. However, such ancient DNA is often fragmented and
damaged, and studies to date have typically focused on short mitochondrial
sequences, never yielding more than a fraction of a per cent of any
nuclear genome. Here we describe 4.17 billion bases (Gb) of sequence from
several mammoth specimens, 3.3 billion (80%) of which are from the woolly
mammoth (Mammuthus primigenius) genome and thus comprise an extensive set
of genome-wide sequence from an extinct species. Our data support earlier
reports that elephantid genomes exceed 4 Gb. The estimated divergence rate
between mammoth and African elephant is half of that between human and
chimpanzee. The observed number of nucleotide differences between two
particular mammoths was approximately one-eighth of that between one of
them and the African elephant, corresponding to a separation between the
mammoths of 1.5-2.0 Myr. The estimated probability that orthologous
elephant and mammoth amino acids differ is 0.002, corresponding to about
one residue per protein. Differences were discovered between mammoth and
African elephant in amino-acid positions that are otherwise invariant over
several billion years of combined mammalian evolution. This study shows
that nuclear genome sequencing of extinct species can reveal population
differences not evident from the fossil record, and perhaps even discover
genetic factors that affect extinction
Nicholls, H.,
2008. Darwin 200: Let's make a mammoth. Nature 456, 310-314.
Nishihara, H.,
Okada, N., 2008. Retroposons: genetic footprints on the evolutionary paths
of life. Methods Mol. Biol. 422, 201-225.
Abstract: Retroposons such as short interspersed elements (SINEs) and long
interspersed elements are abundant transposable elements in eukaryote
genomes. Recent large-scale comparative genome analyses have revealed that
retroposons are a major component of genomes, wherein they provide
structural diversity between species and uniqueness to each species. SINEs
have been used as powerful markers in phylogenetic analyses of various
species. This approach, which has been termed the SINE insertion method,
infers phylogenetic relationships based on the presence/absence of SINEs
among lineages. However, the method is not yet used extensively among
biologists, especially molecular phylogenetists, because it is based on an
understanding of the molecular mechanisms of retroposition, which may be
unfamiliar to many researchers. Moreover, the method may require a large
amount of bench work to characterize a new SINE family and to screen
genomic libraries of the species of interest. In this chapter, we present
the basic theory and detailed technical steps involved in a SINE insertion
analysis. Furthermore, we explain the isolation and characterization of a
new SINE family from the genome of a species of interest using as an
example a known SINE family in mammals
Okello, J.B.,
Wittemyer, G., Rasmussen, H.B., Arctander, P., Nyakaana, S.,
Douglas-Hamilton, I., Siegismund, H.R., 2008. Effective population size
dynamics reveal impacts of historic climatic events and recent
anthropogenic pressure in African elephants. Mol. Ecol. 17,
3788-3799.
Abstract: Two hundred years of elephant hunting for ivory, peaking in
1970-1980s, caused local extirpations and massive population declines
across Africa. The resulting genetic impacts on surviving populations have
not been studied, despite the importance of understanding the evolutionary
repercussions of such human-mediated events on this keystone species.
Using Bayesian coalescent-based genetic methods to evaluate time-specific
changes in effective population size, we analysed genetic variation in 20
highly polymorphic microsatellite loci from 400 elephants inhabiting the
greater Samburu-Laikipia region of northern Kenya. This area experienced a
decline of between 80% and 90% in the last few decades when ivory
harvesting was rampant. The most significant change in effective
population size, however, occurred approximately 2500 years ago during a
mid-Holocene period of climatic drying in tropical Africa. Contrary to
expectations, detailed analyses of four contemporary age-based cohorts
showed that the peak poaching epidemic in the 1970s caused detectable
temporary genetic impacts, with genetic diversity rebounding as juveniles
surviving the poaching era became reproductively mature. This study
demonstrates the importance of climatic history in shaping the
distribution and genetic history of a keystone species and highlights the
utility of coalescent-based demographic approaches in unravelling
ancestral demographic events despite a lack of ancient samples. Unique
insights into the genetic signature of mid-Holocene climatic change in
Africa and effects of recent poaching pressure on elephants are discussed
Okello, J.B.,
Masembe, C., Rasmussen, H.B., Wittemyer, G., Omondi, P., Kahindi, O.,
Muwanika, V.B., Arctander, P., Douglas-Hamilton, I., Nyakaana, S.,
Siegismund, H.R., 2008. Population genetic structure of savannah elephants
in Kenya: conservation and management implications. J. Hered. 99,
443-452.
Abstract: We investigated population genetic structure and regional
differentiation among African savannah elephants in Kenya using
mitochondrial and microsatellite markers. We observed mitochondrial DNA (mtDNA)
nucleotide diversity of 1.68% and microsatellite variation in terms of
average number of alleles, expected and observed heterozygosities in the
total study population of 10.20, 0.75, and 0.69, respectively.
Hierarchical analysis of molecular variance of mtDNA variation revealed
significant differentiation among the 3 geographical regions studied (F(CT)
= 0.264; P < 0.05) and a relatively lower differentiation among
populations within regions (F(SC) = 0.218; P < 0.0001). Microsatellite
variation significantly differentiated among populations within regions (F(SC)
= 0.019; P < 0.0001) but not at the regional levels (F(CT) = 0.000; P >
0.500). We attribute the high differentiation at the mitochondrial genome
to the matrilineal social structure of elephant populations, female natal
philopatry, and probably ancient vicariance. Lack of significant regional
differentiation at the nuclear loci vis-a-vis strong differences at mtDNA
loci between regions is likely the effect of subsequent homogenization
through male-mediated gene flow. Our results depicting 3 broad regional
mtDNA groups and the observed population genetic differentiation as well
as connectivity patterns should be incorporated in the planning of future
management activities such as translocations
Organ, C.L.,
Schweitzer, M.H., Zheng, W., Freimark, L.M., Cantley, L.C., Asara, J.M.,
2008. Molecular phylogenetics of mastodon and Tyrannosaurus rex. Science
320, 499.
Abstract: We report a molecular phylogeny for a nonavian dinosaur,
extending our knowledge of trait evolution within nonavian dinosaurs into
the macromolecular level of biological organization. Fragments of collagen
alpha1(I) and alpha2(I) proteins extracted from fossil bones of
Tyrannosaurus rex and Mammut americanum (mastodon) were analyzed with a
variety of phylogenetic methods. Despite missing sequence data, the
mastodon groups with elephant and the T. rex groups with birds, consistent
with predictions based on genetic and morphological data for mastodon and
on morphological data for T. rex. Our findings suggest that molecular data
from long-extinct organisms may have the potential for resolving
relationships at critical areas in the vertebrate evolutionary tree that
have, so far, been phylogenetically intractable
Pacheco, J.M.,
Traulsen, A., Antal, T., Dingli, D., 2008. Cyclic neutropenia in mammals.
Am. J. Hematol. 83, 920-921.
Abstract: Cyclic neutropenia (CN) has been well documented in humans and
the gray collie. A recent model of the architecture and dynamics of
hematopoiesis has been used to provide insights into the mechanism of
cycling of this disorder. It provides a link between the cycling period
and the cells where the mutated ELA2 is expressed. Assuming that the
biologic defect in CN is the same in dogs, and the observation that the
structure of hematopoiesis is invariant across mammals, we use allometric
scaling techniques to correctly predict the period of cycling in the gray
collie and extend it to other mammals from mice to elephants. This work
provides additional support for the relevance of animal models to
understand disease but cautions that disease dynamics in model animals are
different and this has to be taken into consideration when planning
experiments
Page, J.E.,
Murphy, W.J., 2008. Construction of radiation hybrid panels. Methods Mol.
Biol. 422, 51-64.
Abstract: Whole-genome radiation hybrid (RH) mapping has proven to be a
powerful tool for mapping genes and comparing genome architecture. We
describe a protocol for constructing RH panels by rescuing irradiated
fibroblast donor cells of any mammalian species by polyethylene glycol
fusion to a thymidine kinase-deficient hamster cell line. Characterization
and expansion of a panel of 90-100 cell lines can be used to map virtually
any PCR-based marker that can be distinguished from the recipient hamster
genome. The described procedure has been used successfully to create RH
panels from diverse mammalian species such as macaques, elephants,
alpacas, and armadillos, and may be applicable to nonmammalian vertebrates
as well
Perelygin, A.A.,
Zharkikh, A.A., Astakhova, N.M., Lear, T.L., Brinton, M.A., 2008.
Concerted evolution of vertebrate CCR2 and CCR5 genes and the origin of a
recombinant equine CCR5/2 gene. J. Hered. 99, 500-511.
Abstract: Chemokine receptors (CCRs) play an essential role in the
initiation of an innate immune host response. Several of these receptors
have been shown to modulate the outcome of viral infections. The recent
availability of complete genome sequences from a number of species
provides a unique opportunity to analyze the evolution of the CCR genes. A
phylogenetic analysis revealed that the CCR2 gene evolved in concert with
the paralogous CCR5 gene, but not with another paralogous gene, CCR3, in
the opossum, platypus, rabbit, guinea pig, cat, and rodent lineages. In
addition, evidence of concerted evolution of the CCR2 and CCR5 genes was
observed in chicken and lizard genomes. A unique CCR5/2 gene that
originated by unequal crossing over between the CCR2 and CCR5 genes was
detected in the domestic horse. The CCR2, CCR5, and CCR5/2 genes were
mapped to ECA16q21 using fluorescent in situ hybridization (FISH).
Single-nucleotide polymorphisms identified in the equine CCR5 gene and
characterized within 5 horse breeds provide haplotype markers for future
case/control studies investigating the genetic bases of horse
susceptibility to infectious diseases
Thongtip, N.,
Saikhun, J., Mahasawangkul, S., Kornkaewrat, K., Pongsopavijitr, P.,
Songsasen, N., Pinyopummin, A., 2008. Potential factors affecting semen
quality in the Asian elephant (Elephas maximus). Reprod. Biol. Endocrinol.
6, 9.
Abstract: BACKGROUND: One of the major obstacles in using artificial
insemination to manage genetics of elephant population in captivity is the
large variations in semen quality among ejaculates within the same and
among individuals. The objectives of this study were to determine the
influences of (1) age (2) seasonality (3) and circulating testosterone (SrTest),
triiodothyronine (SrT3) and tetraiodothyronine (SrT4), as well as seminal
(4) testosterone (SpTest), zinc (SpZn) and protein (SpTP) on semen quality
in the Asian elephant METHODS: Analyses, including motility, viability and
morphology were performed in semen samples collected twice monthly from 13
elephant bulls (age range, 10-to 72-years) by manual stimulation between
July 2004 and June 2005. Serum samples obtained monthly were assessed for
SrTest, SrT3, SrT4, and seminal plasma samples were evaluated for, SpTest,
SpZn and SpTP. RESULTS: The highest semen quality was observed at age 23
to 43 years. Percentages of progressive motility and viable sperm were
lowest at age 51 to 70 years (P < 0.05); on the other hand, sperm
concentration was lowest at age 10 to 19 years (P < 0.05). Percentage of
sperm with normal morphology was highest at age 23 to 43 years. The levels
of SrT3, SrTest, SpTest and SpZn were lowest at age 51 to 70 years,
whereas SrT4 was lowest at age 23 to 43 years. Seasonality significantly
affected semen characteristics in which percentage of viable sperm and
cell concentration were highest during rainy season and lowest during
summer months (P < 0.05). However, percentage of sperm with normal
morphology was highest in summer and lowest in rainy season (P < 0.05).
Seasonality significantly influenced SrTest with elevated concentrations
observed in rainy season and winter (P < 0.05). CONCLUSION: This study
indicates that age and seasonality had influence on semen characteristics
in the Asian elephant. The knowledge obtained in this study will improve
our understanding of the reproductive biology of this species
von, A., I,
Nimzyk, R., Klemke, M., Bullerdiek, J., 2008. A microRNA encoded in a
highly conserved part of the mammalian HMGA2 gene. Cancer Genet. Cytogenet.
187, 43-44.
Abstract: The high mobility group protein HMGA2 plays an important role as
a chromatin component of stem cells and as a protein causally related to
the development of a variety of benign tumors (e.g., uterine leiomyomas,
lipomas, and pleomorphic adenomas of the salivary glands). Herein, the
existence of a highly conserved region within intron 3 of HMGA2 encoding a
microRNA is described. The co-expression with HMGA2 suggests that as an
intronic microRNA, this microRNA may cooperate with HMGA2 in its
physiological and/or aberrant functions
Wallis, M.,
2008. Mammalian genome projects reveal new growth hormone (GH) sequences.
Characterization of the GH-encoding genes of armadillo (Dasypus
novemcinctus), hedgehog (Erinaceus europaeus), bat (Myotis lucifugus),
hyrax (Procavia capensis), shrew (Sorex araneus), ground squirrel (Spermophilus
tridecemlineatus), elephant (Loxodonta africana), cat (Felis catus) and
opossum (Monodelphis domestica). Gen. Comp Endocrinol. 155,
271-279.
Abstract: Mammalian growth hormone (GH) sequences have been shown
previously to display episodic evolution: the sequence is generally
strongly conserved but on at least two occasions during mammalian
evolution (on lineages leading to higher primates and ruminants) bursts of
rapid evolution occurred. However, the number of mammalian orders studied
previously has been relatively limited, and the availability of sequence
data via mammalian genome projects provides the potential for extending
the range of GH gene sequences examined. Complete or nearly complete GH
gene sequences for six mammalian species for which no data were previously
available have been extracted from the genome databases-Dasypus
novemcinctus (nine-banded armadillo), Erinaceus europaeus (western
European hedgehog), Myotis lucifugus (little brown bat), Procavia capensis
(cape rock hyrax), Sorex araneus (European shrew), Spermophilus
tridecemlineatus (13-lined ground squirrel). In addition incomplete data
for several other species have been extended. Examination of the data in
detail and comparison with previously available sequences has allowed
assessment of the reliability of deduced sequences. Several of the new
sequences differ substantially from the consensus sequence previously
determined for eutherian GHs, indicating greater variability than
previously recognised, and confirming the episodic pattern of evolution.
The episodic pattern is not seen for signal sequences, 5' upstream
sequence or synonymous substitutions-it is specific to the mature protein
sequence, suggesting that it relates to the hormonal function. The
substitutions accumulated during the course of GH evolution have occurred
mainly on the side of the hormone facing away from the receptor, in a
non-random fashion, and it is suggested that this may reflect interaction
of the receptor-bound hormone with other proteins or small ligands
Wasser, S.K.,
Joseph, C.W., Drori, O., Stephen, K.E., Mailand, C., Mutayoba, B.,
Stephens, M., 2008. Combating the illegal trade in African elephant ivory
with DNA forensics. Conserv. Biol. 22, 1065-1071.
Abstract: International wildlife crime is burgeoning in this climate of
global trade. We contend that the most effective way to contain this
illegal trade is to determine where the wildlife is being removed. This
allows authorities to direct law enforcement to poaching hot spots,
potentially stops trade before the wildlife is actually killed, prevents
countries from denying their poaching problems at home, and thwarts trade
before it enters into an increasingly complex web of international
criminal activity. Forensic tools have been limited in their ability to
determine product origin because the information they can provide
typically begins only at the point of shipment. DNA assignment analyses
can determine product origin, but its use has been limited by the
inability to assign samples to locations where reference samples do not
exist. We applied new DNA assignment methods that can determine the
geographic origin(s) of wildlife products from anywhere within its range.
We used these methods to examine the geographic origin(s) of 2 strings of
seizures involving large volumes of elephant ivory, 1 string seized in
Singapore and Malawi and the other in Hong Kong and Cameroon. These ivory
traffickers may comprise 2 of the largest poaching rings in Africa. In
both cases all ivory seized in the string had common origins, which
indicates that crime syndicates are targeting specific populations for
intense exploitation. This result contradicts the dominant belief that
dealers are using a decentralized plan of procuring ivory stocks as they
became available across Africa. Large quantities of ivory were then moved,
in multiple shipments, through an intermediate country prior to shipment
to Asia, as a risk-reduction strategy that distances the dealer from the
poaching locale. These smuggling strategies could not have been detected
by forensic information, which typically begins only at the shipping
source
Asara, J.M.,
Schweitzer, M.H., Freimark, L.M., Phillips, M., Cantley, L.C., 2007.
Protein sequences from mastodon and Tyrannosaurus rex revealed by mass
spectrometry. Science 316, 280-285.
Abstract: Fossilized bones from extinct taxa harbor the potential for
obtaining protein or DNA sequences that could reveal evolutionary links to
extant species. We used mass spectrometry to obtain protein sequences from
bones of a 160,000- to 600,000-year-old extinct mastodon (Mammut
americanum) and a 68-million-year-old dinosaur (Tyrannosaurus rex). The
presence of T. rex sequences indicates that their peptide bonds were
remarkably stable. Mass spectrometry can thus be used to determine unique
sequences from ancient organisms from peptide fragmentation patterns, a
valuable tool to study the evolution and adaptation of ancient taxa from
which genomic sequences are unlikely to be obtained. Division of Signal
Transduction, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA.
jasara@bidmc.harvard.edu
Barnes, I.,
Shapiro, B., Lister, A., Kuznetsova, T., Sher, A., Guthrie, D., Thomas,
M.G., 2007. Genetic structure and extinction of the woolly mammoth,
Mammuthus primigenius. Curr. Biol. 17, 1072-1075.
Abstract: The interval since circa 50 Ka has been a period of significant
species extinctions among the large mammal fauna. However, the relative
roles of an increasing human presence and a synchronous series of complex
environmental changes in these extinctions have yet to be fully resolved.
Recent analyses of fossil material from Beringia have clarified our
understanding of the spatiotemporal pattern of Late Pleistocene
extinctions, identifying periods of population turnover well before the
last glacial maximum (LGM: circa 21 Ka) or subsequent human expansion. To
examine the role of pre-LGM population changes in shaping the genetic
structure of an extinct species, we analyzed the mitochondrial DNA of
woolly mammoths in western Beringia and across its range. We identify
genetic signatures of a range expansion of mammoths, from eastern to
western Beringia, after the last interglacial (circa 125 Ka), and then an
extended period during which demographic inference indicates no
population-size increase. The most marked change in diversity at this time
is the loss of one of two major mitochondrial lineages
Binladen, J.,
Gilbert, M.T., Willerslev, E., 2007. 800,000 year old mammoth DNA, modern
elephant DNA or PCR artefact? Biol. Lett. 3, 55-56.
Abstract: Poulakakis and colleagues (Poulakakis et al. 2006: Biol. Lett.
2, 451-454), report the recovery of 'authentic' mammoth DNA from an
800,000-year-old fragment of bone excavated on the island of Crete. In
light of results from other ancient DNA studies that indicate how DNA
survival is unlikely in samples, which are recovered from warm
environments and are relatively old (e.g. more than 100,000 years), these
findings come as a great surprise. Here, we show that problems exist with
the methodological approaches used in the study. First, the nested PCR
technique as reported is nonsensical--one of the second round 'nested'
primers falls outside the amplicon of the first round PCR. More
worryingly, the binding region of one of the first round primers
(Elcytb320R) falls within the short 43 base pair reported mammoth
sequence, specifically covering two of the three reportedly diagnostic
Elephas polymorphisms. Finally, we demonstrate using a simple BLAST search
in GenBank that the claimed 'uniquely derived character state' for
mammoths is in fact also found within modern elephants
Gilbert, M.T.,
Binladen, J., Miller, W., Wiuf, C., Willerslev, E., Poinar, H., Carlson,
J.E., Leebens-Mack, J.H., Schuster, S.C., 2007. Recharacterization of
ancient DNA miscoding lesions: insights in the era of
sequencing-by-synthesis
422. Nucleic Acids Res. 35, 1-10.
Abstract: Although ancient DNA (aDNA) miscoding lesions have been studied
since the earliest days of the field, their nature remains a source of
debate. A variety of conflicting hypotheses exist about which miscoding
lesions constitute true aDNA damage as opposed to PCR polymerase
amplification error. Furthermore, considerable disagreement and
speculation exists on which specific damage events underlie observed
miscoding lesions. The root of the problem is that it has previously been
difficult to assemble sufficient data to test the hypotheses, and
near-impossible to accurately determine the specific strand of origin of
observed damage events. With the advent of emulsion-based clonal
amplification (emPCR) and the sequencing-by-synthesis technology this has
changed. In this paper we demonstrate how data produced on the Roche GS20
genome sequencer can determine miscoding lesion strands of origin, and
subsequently be interpreted to enable characterization of the aDNA damage
behind the observed phenotypes. Through comparative analyses on 390,965 bp
of modern chloroplast and 131,474 bp of ancient woolly mammoth GS20
sequence data we conclusively demonstrate that in this sample at least, a
permafrost preserved specimen, Type 2
(cytosine-->thymine/guanine-->adenine) miscoding lesions represent the
overwhelming majority of damage-derived miscoding lesions. Additionally,
we show that an as yet unidentified guanine-->adenine analogue
modification, not the conventionally argued cytosine-->uracil deamination,
underpins a significant proportion of Type 2 damage. How widespread these
implications are for aDNA will become apparent as future studies analyse
data recovered from a wider range of substrates
Hollister-Smith, J.A., Poole, J.H., Archie, E.A., Vance, E.A., Georgiadis,
N.J., Moss, C.J., Alberts, S.C., 2007. Age, musth and paternity success in
wild maleAfrican elephants, Loxodonta africana. Animal Behaviour 74,
287-296.
Abstract: Male African elephants experience intense intrasexual selection
in gaining access to oestrous females, who represent a very scarce and
highly mobile resource. An unusual combination of behavioural and
physiologica ltraits in males probably reflects this intense selection
pressure. Males show prolonged growth, growing throughout much or perhaps
all of their long life span (ca. 60-65 years), and they show musth,a
physiological and behavioural condition exclusive to elephants, which is
manifested by bouts of elevated testosterone and aggression and heightened
sexual activity. Most observed matings are by males over 35years of age
and in musth, suggesting that age and musth are both important factors
contributing to male reproductive success. Here we report the results of a
genetic paternity analysis of a well-studied population of wild African
elephants. Patterns of paternity for 119 calves born over a 22-year period
showed significant effects of both age and musth on paternity success.
Among males in musth, paternity success increased significantly with age
until the very oldest age classes, when it modestly declined. When not
inmusth, males experienced relatively constant, low levels of paternity
success at all ages. Thus, despite the importance of both musth and age in
determining male paternity success, adult males both in and out ofmusth,
and of all ages, produced calves. In general, however, older males had
markedly elevated paternitysuccess compared with younger males, suggesting
the possibility of sexual selection for longevity in this species.
Hubbard, T.J.,
Aken, B.L., Beal, K., Ballester, B., Caccamo, M., Chen, Y., Clarke, L.,
Coates, G., Cunningham, F., Cutts, T., Down, T., Dyer, S.C., Fitzgerald,
S., Fernandez-Banet, J., Graf, S., Haider, S., Hammond, M., Herrero, J.,
Holland, R., Howe, K., Howe, K., Johnson, N., Kahari, A., Keefe, D.,
Kokocinski, F., Kulesha, E., Lawson, D., Longden, I., Melsopp, C., Megy,
K., Meidl, P., Ouverdin, B., Parker, A., Prlic, A., Rice, S., Rios, D.,
Schuster, M., Sealy, I., Severin, J., Slater, G., Smedley, D., Spudich,
G., Trevanion, S., Vilella, A., Vogel, J., White, S., Wood, M., Cox, T.,
Curwen, V., Durbin, R., Fernandez-Suarez, X.M., Flicek, P., Kasprzyk, A.,
Proctor, G., Searle, S., Smith, J., Ureta-Vidal, A., Birney, E., 2007.
Ensembl 2007. Nucleic Acids Res. 35, D610-D617.
Abstract: The Ensembl (http://www.ensembl.org/) project provides a
comprehensive and integrated source of annotation of chordate genome
sequences. Over the past year the number of genomes available from Ensembl
has increased from 15 to 33, with the addition of sites for the mammalian
genomes of elephant, rabbit, armadillo, tenrec, platypus, pig, cat, bush
baby, common shrew, microbat and european hedgehog; the fish genomes of
stickleback and medaka and the second example of the genomes of the sea
squirt (Ciona savignyi) and the mosquito (Aedes aegypti). Some of the
major features added during the year include the first complete gene sets
for genomes with low-sequence coverage, the introduction of new strain
variation data and the introduction of new orthology/paralog annotations
based on gene trees
Kellogg, M.E.,
Burkett, S., Dennis, T.R., Stone, G., Gray, B.A., McGuire, P.M., Zori, R.T.,
Stanyon, R., 2007. Chromosome painting in the manatee supports Afrotheria
and Paenungulata. BMC. Evol. Biol. 7, 6.
Abstract: BACKGROUND: Sirenia (manatees, dugongs and Stellar's sea cow)
have no evolutionary relationship with other marine mammals, despite
similarities in adaptations and body shape. Recent phylogenomic results
place Sirenia in Afrotheria and with elephants and rock hyraxes in
Paenungulata. Sirenia and Hyracoidea are the two afrotherian orders as yet
unstudied by comparative molecular cytogenetics. Here we report on the
chromosome painting of the Florida manatee. RESULTS: The human autosomal
and X chromosome paints delimited a total of 44 homologous segments in the
manatee genome. The synteny of nine of the 22 human autosomal chromosomes
(4, 5, 6, 9, 11, 14, 17, 18 and 20) and the X chromosome were found intact
in the manatee. The syntenies of other human chromosomes were disrupted in
the manatee genome into two to five segments. The hybridization pattern
revealed that 20 (15 unique) associations of human chromosome segments are
found in the manatee genome: 1/15, 1/19, 2/3 (twice), 3/7 (twice), 3/13,
3/21, 5/21, 7/16, 8/22, 10/12 (twice), 11/20, 12/22 (three times), 14/15,
16/19 and 18/19. CONCLUSION: There are five derived chromosome traits that
strongly link elephants with manatees in Tethytheria and give implicit
support to Paenungulata: the associations 2/3, 3/13, 8/22, 18/19 and the
loss of the ancestral eutherian 4/8 association. It would be useful to
test these conclusions with chromosome painting in hyraxes. The manatee
chromosome painting data confirm that the associations 1/19 and 5/21
phylogenetically link afrotherian species and show that Afrotheria is a
natural clade. The association 10/12/22 is also ubiquitous in Afrotheria (clade
I), present in Laurasiatheria (clade IV), only partially present in
Xenarthra (10/12, clade II) and absent in Euarchontoglires (clade III). If
Afrotheria is basal to eutherians, this association could be part of the
ancestral eutherian karyotype. If afrotherians are not at the root of the
eutherian tree, then the 10/12/22 association could be one of a suite of
derived associations linking afrotherian taxa
Kirkpatrick,
J.F., 2007. Measuring the effects of wildlife contraception: the argument
for comparing apples with oranges. Reprod. Fertil. Dev. 19,
548-552.
Abstract: There are few wildlife populations existing today that can be
supported without some form of management. Wildlife fertility control, as
one option, has moved from the research stage to actual application with a
number of species, including wild horses, urban deer, captive exotic
species and even African elephants, but this approach remains
controversial in many quarters. Strident debate has arisen over the
possible effects of contraception on behaviour, genetics, stress and even
management economics, among other parameters. Part of the debate arises
from the fact that critics often fail to recognise that some form of
alternative management will be applied, and a second problem arises when
critics fail to identify and demand the same concern for the consequences
of the alternative management approaches. Thus, any rational debate on the
merits or possible effects of contraceptive management of wildlife must
also recognise all alternative management approaches and apply the same
concern and questions to these alternative approaches--including 'no
management'--as are currently being applied to fertility control. Only
then will the stewards of wildlife be in a position to make wise and
informed decisions about management options
Kullberg, M.,
Hallström, B., Arnason, U., Janke, A., 2007. Expressed sequence tags as a
tool for phylogenetic analysis of placental mammal evolution. PLoS ONE E
publication Aug 22;2(1):e775.
Abstract: BACKGROUND: We investigate the usefulness of expressed sequence
tags, ESTs, for establishing divergences within the tree of placental
mammals. This is done on the example of the established relationships
among primates (human), lagomorphs (rabbit), rodents (rat and mouse),
artiodactyls (cow), carnivorans (dog) and proboscideans (elephant).
METHODOLOGY/PRINCIPAL FINDINGS: We have produced 2000 ESTs (1.2 mega
bases) from a marsupial mouse and characterized the data for their use in
phylogenetic analysis. The sequences were used to identify putative
orthologous sequences from whole genome projects. Although most ESTs stem
from single sequence reads, the frequency of potential sequencing errors
was found to be lower than allelic variation. Most of the sequences
represented slowly evolving housekeeping-type genes, with an average amino
acid distance of 6.6% between human and mouse. Positive Darwinian
selection was identified at only a few single sites. Phylogenetic analyses
of the EST data yielded trees that were consistent with those established
from whole genome projects. CONCLUSIONS: The general quality of EST
sequences and the general absence of positive selection in these sequences
make ESTs an attractive tool for phylogenetic analysis. The EST approach
allows, at reasonable costs, a fast extension of data sampling from
species outside the genome projects.
Lynn, D.J.,
Bradley, D.G., 2007. Discovery of alpha-defensins in basal mammals. Dev.
Comp Immunol. 31, 963-967.
Abstract: Alpha-defensins are essential molecules of the innate immune
system that have broad spectrum antimicrobial activity against a range of
bacteria and viruses. To date, alpha-defensins have only been identified
in the Euarchontoglires branch of the mammals. This has led to speculation
that alpha-defensins may be specific to this group, a somewhat surprising
finding, given their importance in the immune system. The mammalian genome
project provided us with the opportunity to search for alpha-defensins in
previously unexamined mammalian superorders. Using hidden Markov model
(HMM) profile searching, we report the discovery of alpha-defensins in the
African savanna elephant, the lesser hedgehog tenrec, and the nine-banded
armadillo genomes representing two of the most basal mammalian superorders,
Afrotheria and Xenarthra. Furthermore, we identify an alpha-defensin-like
gene in the gray short-tailed opossum, suggesting that alpha-defensins may
have evolved much earlier than previously thought, before the divergence
of placental mammals and marsupials approximately 130 mya
Mailand, C.,
Wasser, S.K., 2007. Isolation of DNA from small amounts of elephant ivory.
Nat Protoc 2, 2228-2232.
Abstract: This protocol describes a method for the extraction of DNA from
elephant ivory. These techniques are being used to assign geographic
origin to poached ivory by comparing the ivory genotype to a
geographic-based gene frequency map, developed separately. The method has
three components: ivory pulverization, decalcification and DNA extraction.
Pulverization occurs in a freezer mill while the sample is deep frozen in
liquid nitrogen, preventing degradation of DNA during the process.
Decalcification involves repeated agitation of the sample in 0.5 M
ethylenediaminetetraacetic acid over a 4-d period. Extraction follows a
modified Qiagen protocol for the extraction of DNA from animal tissue.
This method can be used on all forms of ivory. However, DNA recovery is
highest when the outermost layer of the tusk, the cementum, is used. When
applied to extract DNA from 11 samples, in duplicate, the entire protocol
can be completed in 6 d, although much of this time consists of pause
points that do not require effort. The protocol provides 0.8 +/- 0.11 ng
microl(-1) (mean +/- s.e., n = 48) of DNA per sample.
Matsumoto, K.,
Parola, P., Rolain, J.M., Jeffery, K., Raoult, D., 2007. Detection of "Rickettsia
sp. strain Uilenbergi" and "Rickettsia sp. strain Davousti" in Amblyomma
tholloni ticks from elephants in Africa. BMC Microbiol 7, 74 [Epub
ahead of print].
Abstract: ABSTRACT: BACKGROUND: To date, 6 tick-borne rickettsiae
pathogenic for humans are known to occur in Africa and 4 of them were
first identified in ticks before being recognized as human pathogens.
RESULTS: We examined 33 and 5 Amblyomma tholloni ticks from African
elephants in the Central African Republic and Gabon, respectively, by PCR
amplification and sequencing of a part of gltA and ompA genes of the genus
Rickettsia. The partial sequences of gltA and ompA genes detected in tick
in Gabon had 99.1% similarity with those of R. heilongjiangensis and 97.1%
with those of Rickettsia sp. HL-93 strain, respectively. The partial gltA
and ompA gene sequences detected in tick in the Central African Republic
were 98.9% and 95.1% similar to those of Rickettsia sp. DnS14 strain and
R. massiliae, respectively. Phylogenetic analysis showed Rickettsia sp.
detected in Gabon clusters with R. japonica and R. heilongjiangensis in a
phylogenetic tree based on the partial gltA and ompA genes. The genotype
of the Rickettsia sp. detected in the Central African Republic is close to
those of R. massiliae group in the phylogenetic tree based on partial gltA
gene sequences, and distantly related to other rickettsiae in the tree
based on partial ompA gene. CONCLUSIONS: The degrees of similarity of
partial gltA and ompA genes with recognized species indicate the
rickettsiae detected in this study may be new species although we could
only study the partial sequences of 2 genes regarding the amount of DNA
that was available. We propose the Rickettsia sp. detected in Gabon be
provisionally named "Rickettsia sp. stain Davousti" and Rickettsia sp.
detected in the Central African Republic be named "Rickettsia sp. strain
Uilenbergi".
Murphy, W.J.,
Pringle, T.H., Crider, T.A., Springer, M.S., Miller, W., 2007. Using
genomic data to unravel the root of the placental mammal phylogeny. Genome
Res. 17, 413-421.
Abstract: The phylogeny of placental mammals is a critical framework for
choosing future genome sequencing targets and for resolving the ancestral
mammalian genome at the nucleotide level. Despite considerable recent
progress defining superordinal relationships, several branches remain
poorly resolved, including the root of the placental tree. Here we
analyzed the genome sequence assemblies of human, armadillo, elephant, and
opossum to identify informative coding indels that would serve as rare
genomic changes to infer early events in placental mammal phylogeny. We
also expanded our species sampling by including sequence data from >30
ongoing genome projects, followed by PCR and sequencing validation of each
indel in additional taxa. Our data provide support for a sister-group
relationship between Afrotheria and Xenarthra (the Atlantogenata
hypothesis), which is in turn the sister-taxon to Boreoeutheria. We failed
to recover any indels in support of a basal position for Xenarthra (Epitheria),
which is suggested by morphology and a recent retroposon analysis, or a
hypothesis with Afrotheria basal (Exafricoplacentalia), which is favored
by phylogenetic analysis of large nuclear gene data sets. In addition, we
identified two retroposon insertions that also support Atlantogenata and
none for the alternative hypotheses. A revised molecular timescale based
on these phylogenetic inferences suggests Afrotheria and Xenarthra
diverged from other placental mammals approximately 103 (95-114) million
years ago. We discuss the impacts of this topology on earlier phylogenetic
reconstructions and repeat-based inferences of phylogeny
Orlando, L.,
Pages, M., Calvignac, S., Hughes, S., Hanni, C., 2007. Does the 43 bp
sequence from an 800,000 year old cretan dwarf elephantid really rewrite
the textbook on mammoths? Biol. Lett. 3, 57-59.
Abstract: Pigmy elephants inhabited the islands from the Mediterranean
region during the Pleistocene period but became extinct in the course of
the Holocene. Despite striking distinctive anatomical characteristics
related to insularity, some similarities with the lineage of extant Asian
elephants have suggested that pigmy elephants could be most probably seen
as members of the genus Elephas. Poulakakis et al (2006) have recently
challenged this view by recovering a short mtDNA sequence from an 800 000
year old fossil of the Cretan pigmy elephant (Elephas creticus). According
to the authors of this study, a deep taxonomic revision of Cretan dwarf
elephants would be needed, as the sequence exhibits clear affinities with
woolly mammoth haplotypes. However, we point here many aspects that
seriously weaken the strength of the ancient DNA evidence reported
Orlando, L.,
Hanni, C., Douady, C.J., 2007. Mammoth and Elephant Phylogenetic
Relationships: Mammut Americanum, the Missing Outgroup. Evol. Bioinform.
Online. 3, 45-51.
Abstract: At the morphological level, the woolly mammoth has most often
been considered as the sister-species of Asian elephants, but at the DNA
level, different studies have found support for proximity with African
elephants. Recent reports have increased the available sequence data and
apparently solved the discrepancy, finding mammoths to be most closely
related to Asian elephants. However, we demonstrate here that the three
competing topologies have similar likelihood, bayesian and parsimony
supports. The analysis further suggests the inadequacy of using Sirenia or
Hyracoidea as outgroups. We therefore argue that orthologous sequences
from the extinct American mastodon will be required to definitively solve
this long-standing question
Orlando, L.,
Pages, M., Calvignac, S., Hughes, S., Hanni, C., 2007. Does the 43 bp
sequence from an 800,000 year old Cretan dwarf elephantid really rewrite
the textbook on mammoths? Biology Letters 3, 57-59.
Abstract: Pigmy elephants inhabited the islands from the Mediterranean
region during the Pleistocene period but became extinct in the course of
the Holocene. Despite striking distinctive anatomical characteristics
related to insularity, some similarities with the lineage of extant Asian
elephants have suggested that pigmy elephants could be most probably seen
as members of the genus Elephas. Poulakakis et al. (2006) have recently
challenged this view by recovering a short mtDNA sequence from an 800 000
year old fossil of the Cretan pigmy elephant (Elephas creticus). According
to the authors of this study, a deep taxonomic revision of Cretan dwarf
elephants would be needed, as the sequence exhibits clear affinities with
woolly mammoth haplotypes. However, we point here many aspects that
seriously weaken the strength of the ancient DNA evidence reported.
Pan, D., 2007.
Hippo signaling in organ size control. Genes Dev. 21, 886-897.
Abstract: The control of organ (or organism) size is a fundamental aspect
of life that has long captured human imagination. What makes an elephant
grow a million times larger than a mouse? How do our two hands develop
independently of each other yet reach very similar size? How does a liver
precisely regenerate its original mass when two-thirds of it is removed?
The recent discovery of a novel signaling network in Drosophila, known as
the Hippo (Hpo) pathway, might provide an important entry point to these
fascinating questions. The Hpo pathway consists of several negative growth
regulators acting in a kinase cascade that ultimately phosphorylates and
inactivates Yorkie (Yki), a transcriptional coactivator that positively
regulates cell growth, survival, and proliferation. Components of the Hpo
pathway are highly conserved throughout evolution, suggesting that this
pathway may function as a global regulator of tissue homeostasis in all
metazoan animals. Here, I provide a historical review of this potent
growth-regulatory pathway and highlight outstanding questions that will
likely be the focus of future investigation
Pardini, A.T.,
O'Brien, P.C., Fu, B., Bonde, R.K., Elder, F.F., Ferguson-Smith, M.A.,
Yang, F., Robinson, T.J., 2007. Chromosome painting among Proboscidea,
Hyracoidea and Sirenia: support for Paenungulata (Afrotheria, Mammalia)
but not Tethytheria. Proc. Biol. Sci. 274, 1333-1340.
Abstract: Despite marked improvements in the interpretation of systematic
relationships within Eutheria, particular nodes, including Paenungulata (Hyracoidea,
Sirenia and Proboscidea), remain ambiguous. The combination of a rapid
radiation, a deep divergence and an extensive morphological
diversification has resulted in a limited phylogenetic signal confounding
resolution within this clade both at the morphological and nucleotide
levels. Cross-species chromosome painting was used to delineate regions of
homology between Loxodonta africana (2n=56), Procavia capensis (2n=54),
Trichechus manatus latirostris (2n=48) and an outgroup taxon, the aardvark
(Orycteropus afer, 2n=20). Changes specific to each lineage were
identified and although the presence of a minimum of 11 synapomorphies
confirmed the monophyly of Paenungulata, no change characterizing
intrapaenungulate relationships was evident. The reconstruction of an
ancestral paenungulate karyotype and the estimation of rates of
chromosomal evolution indicate a reduced rate of genomic repatterning
following the paenungulate radiation. In comparison to data available for
other mammalian taxa, the paenungulate rate of chromosomal evolution is
slow to moderate. As a consequence, the absence of a chromosomal character
uniting two paenungulates (at the level of resolution characterized in
this study) may be due to a reduced rate of chromosomal change relative to
the length of time separating successive divergence events
Redi, C.A.,
Garagna, S., Zuccotti, M., Capanna, E., 2007. Genome size: a novel genomic
signature in support of Afrotheria. Journal of Molecular Evolution 64,
484-487.
Abstract: Molecular phylogenetic analyses suggest an emerging phylogeny
for the extant Placentalia (eutherian) that radically departs from
morphologically based constructions of the past. Placental mammals are
partitioned into four supraordinal clades: Afrotheria, Xenarthra,
Laurasiatheria, and Euarchontoglires. Afrotheria form an endemic African
clade that includes elephant shrews, golden moles, tenrecs, aardvarks,
hyraxes, elephants, dugongs, and manatees. Datamining databases of genome
size (GS) shows that till today just one afrotherian GS has been
evaluated, that of the aardvark Orycteropus afer. We show that the GSs of
six selected representatives across the Afrotheria supraordinal group are
among the highest for the extant Placentalia, providing a novel genomic
signature of this enigmatic group. The mean GS value of Afrotheria, 5.3
+/- 0.7 pg, is the highest reported for the extant Placentalia. This
should assist in planning new genome sequencing initiatives
Roca, A.L.,
Georgiadis, N., O'Brien, S.J., 2007. Cyto-nuclear genomic dissociation and
the African elephant species question. Quat. Int. 169-170, 4-16.
Abstract: Studies of skull morphology and of nuclear DNA have strongly
concluded that African elephants comprise two species. Nonetheless,
Debruyne (2005) has suggested a single-species model for Loxodonta based
on the polyphyly of a single genetic locus, mitochondrial DNA (mtDNA).
Discordant patterns between mitochondrial and nuclear DNA markers were
subsequently reported in some African savanna elephant populations,
further supporting a two-species model, and prompting us to re-examine
here the geographic distribution of different elephant morphotypes and
their relationship to nuclear and mtDNA phylogeographic patterns. We used
exact tests to compare the distribution of forest elephant-typical and
savanna elephant-typical characteristics across eight published datasets
containing morphological, mtDNA or nuclear DNA data for African elephants.
Among the elephants examined by Debruyne (2005), we found that patterns of
forest vs. savanna characteristics were significantly different (p <
10(-5)) between mtDNA and morphology, suggesting the presence of cyto-nuclear
genomic dissociation. We show that the eight African elephant
continent-wide datasets compared, including that of Debruyne (2005),
together support a two-species model with cyto-nuclear genomic
dissociation rather than a one-species model, and together indicate that
Africa harbors two species of elephant
Rohland, N.,
Malaspinas, A.S., Pollack, J.L., Slatkin, M., Matheus, P., 2007.
Proboscidean mitogenomics: Chronology and mode of elephant evolution using
mastodon as outgroup. PLoS Biol 5, e207.
doi:10.1371/journal.pbio.0050207.
Abstract: We have sequenced the complete mitochondrial genome of the
extinct American mastodon (Mammut americanum) from an Alaskan fossil that
is between 50,000 and 130,000 y old, extending the age range of genomic
analyses by almost a complete glacial cycle. The sequence we obtained is
substantially different from previously reported partial mastodon
mitochondrial DNA sequences. By comparing those partial sequences to other
proboscidean sequences, we conclude that we have obtained the first
sequence of mastodon DNA ever reported. Using the sequence of the
mastodon, which diverged 24-28 million years ago (mya) from the
Elephantidae lineage, as an outgroup, we infer that the ancestors of
African elephants diverged from the lineage leading to mammoths and Asian
elephants approximately 7.6 mya and that mammoths and Asian elephants
diverged approximately 6.7 mya. We also conclude
that the nuclear genomes of the African savannah and forest elephants
diverged approximately 4.0 mya, supporting the view that these two groups
represent different species. Finally, we found the mitochondrial mutation
rate of proboscideans to be roughly half of the rate in primates during at
least the last 24 million years.
Sreekumar, E.,
Janki, M.B., Arathy, D.S., Hariharan, R., Premraj, C.A., Rasool, T.J.,
2007. Molecular characterization and expression of interferon-gamma of
Asian elephant (Elephas maximus). Vet. Immunol. Immunopathol. 118,
75-83.
Abstract: Tuberculosis (TB) caused by Mycobacterial organisms has emerged
as one of the major diseases in captive elephants. In vitro
Interferon-gamma (IFN-gamma) assay is being used as an ancillary test for
early detection of TB in domestic and captive wild animals. In the present
study, basic sequence information and immunological cross-reactivity of
this major cytokine of Asian elephants were explored. At predicted amino
acid level, IFN-gamma of Asian elephant showed maximum identity to that of
horse (73%). Other IFN-gamma amino acid sequences that showed high level
identity were that of giant panda (72%), dog (71%), nine-banded armadillo
(69%), cattle (63%) and human (62%). IFN-gamma promoter sequences of Asian
elephant, human, cattle and mouse showed high level conservation of the
putative transcription factor binding sites, TATA box and transcriptional
start site. The functionally important human IFN-gamma promoter elements,
such as AP-2IRE-BE, YY1-gammaIFN-BED, ATFCS and AP-1gammaINF binding
sites, were absolutely conserved in the corresponding elephant sequence.
There was only a single nucleotide variation in the other two important
elements, NFAT-gammaINF and IFN-gammaPE, indicating the highly conserved
regulation of IFN-gamma expression across different species. Phylogenetic
analysis based on IFN-gamma protein sequences revealed a closer relation
of Asian elephants and nine-banded armadillo. This shows a closer
evolution of these members of Afrotheria and Xenarthra, respectively; and
supports the previous reports based on mitochondrial DNA studies. In
Western blot analysis, IFN-gamma of Asian elephant expressed in
Escherichia coli was detected using an anti-bovine IFN-gamma monoclonal
antibody, indicating immunological cross-reactivity
Tabuce, R.,
Marivaux, L., Adaci, M., Bensalah, M., Hartenberger, J.L., Mahboubi, M.,
Mebrouk, F., Tafforeau, P., Jaeger, J.J., 2007. Early Tertiary mammals
from North Africa reinforce the molecular Afrotheria clade. Proc. Biol.
Sci. 274, 1159-1166.
Abstract: The phylogenetic pattern and timing of the radiation of mammals,
especially the geographical origins of major crown clades, are areas of
controversy among molecular biologists, morphologists and palaeontologists.
Molecular phylogeneticists have identified an Afrotheria clade, which
includes several taxa as different as tenrecs (Tenrecidae), golden moles (Chrysochloridae),
elephant-shrews (Macroscelididae), aardvarks (Tubulidentata) and
paenungulates (elephants, sea cows and hyracoids). Molecular data also
suggest a Cretaceous African origin for Afrotheria within Placentalia
followed by a long period of endemic evolution on the Afro-Arabian
continent after the mid-Cretaceous Gondwanan breakup (approx. 105-25 Myr
ago). However, there was no morphological support for such a natural
grouping so far. Here, we report new dental and postcranial evidence of
Eocene stem hyrax and macroscelidid from North Africa that, for the first
time, provides a congruent phylogenetic view with the molecular Afrotheria
clade. These new fossils imply, however, substantial changes regarding the
historical biogeography of afrotheres. Their long period of isolation in
Africa, as assumed by molecular inferences, is now to be reconsidered
inasmuch as Eocene paenungulates and elephant-shrews are here found to be
related to some Early Tertiary Euramerican 'hyopsodontid condylarths'
(archaic hoofed mammals). As a result, stem members of afrotherian clades
are not strictly African but also include some Early Paleogene Holarctic
mammals
Wasser, S.K.,
Mailand, C., Booth, R., Mutayoba, B., Kisamo, E., Clark, B., Stephens, M.,
2007. Using DNA to track the origin of the largest ivory seizure since the
1989 trade ban. Proc. Natl. Acad. Sci. U. S. A 104 , 4228-4233.
Abstract: The illegal ivory trade recently intensified to the highest
levels ever reported. Policing this trafficking has been hampered by the
inability to reliably determine geographic origin of contraband ivory.
Ivory can be smuggled across multiple international borders and along
numerous trade routes, making poaching hotspots and potential trade routes
difficult to identify. This fluidity also makes it difficult to refute a
country's denial of poaching problems. We extend an innovative DNA
assignment method to determine the geographic origin(s) of large elephant
ivory seizures. A Voronoi tessellation method is used that utilizes
genetic similarities across tusks to simultaneously infer the origin of
multiple samples that could have one or more common origin(s). We show
that this joint analysis performs better than sample-by-sample methods in
assigning sample clusters of known origin. The joint method is then used
to infer the geographic origin of the largest ivory seizure since the 1989
ivory trade ban. Wildlife authorities initially suspected that this ivory
came from multiple locations across forest and savanna Africa. However, we
show that the ivory was entirely from savanna elephants, most probably
originating from a narrow east-to-west band of southern Africa, centered
on Zambia. These findings enabled law enforcement to focus their
investigation to a smaller area and fewer trade routes and led to changes
within the Zambian government to improve antipoaching efforts. Such
outcomes demonstrate the potential of genetic analyses to help combat the
expanding wildlife trade by identifying origin(s) of large seizures of
contraband ivory. Broader applications to wildlife trade are discussed
Weiss, B., Faus,
H., Haendler, B., 2007. Phylogenetic conservation of the androgen receptor
AR45 variant form in placental mammals. Gene 399, 105-111.
Abstract: A cDNA coding for a tissue-specific AR45 variant form of the
androgen receptor (AR) has recently been identified in humans, with
highest expression levels found in heart. The deduced protein comprises
the DNA-binding domain, hinge region and ligand-binding domain of the AR,
but not the N-terminal domain which is replaced by a unique, short, seven
amino-acid-long stretch. This sequence is encoded by the mutually
exclusive exon 1B, located between exons 1 and 2 of the human AR gene. As
transcript variants of the steroid receptor family have been shown to have
important implications for hormone function, we set out to analyse the
genomes of different organisms for potential AR45 expression. We found
exon 1B to be conserved in the syntenic chromosomal region of non-human
primates such as the chimpanzee Pan troglodytes, the orang-utan Pongo
pygmaeus, the macaque Macaca mulatta and the marmoset Callithrix jacchus,
and of the elephant Loxondonta africana, the pig Sus scrofa and the dog
Canis familiaris. Quantification of AR45 transcript levels in heart,
skeletal muscle and lung of Macaca fascicularis showed the heart to be the
main organ of expression. A complete AR45 cDNA was furthermore isolated
from the heart of this species. Comparative analysis of the identified
AR45 exon 1B regions and of the deduced amino acids revealed a high
conservation among species. The four N-terminal residues were identical in
all eight species, whereas a few changes were seen in the other three
residues in the marmoset, elephant and pig. In contrast, we observed more
divergence in the mouse Mus musculus and rat Rattus norvegicus syntenic
regions. Here a stop codon was found downstream of the potential start
codon in the putatively deduced protein sequence and it can be inferred
that no protein corresponding to AR45 exists in these two species. The
existence of AR45 in different placental mammals with the exception of
mouse and rat suggests a disappearance in rodents late in evolution,
before the separation of the mouse and rat lineages, about 16 million
years ago. In view of the potential function of AR45 as a regulator of AR
function, and considering the multiple roles of androgens in normal
physiology and in several diseases, these findings have important
implications with regard to subtle differences in the action of the male
sexual hormone in various organisms
Wellehan, J.F.,
Johnson, A.J., Childress, A.L., Harr, K.E., Isaza, R., 2007. Six novel
gammaherpesviruses of Afrotheria provide insight into the early divergence
of the Gammaherpesvirinae. Vet Microbiol 2007 Aug 19; [Epub ahead of
print].
Abstract: The Afrotheria represent an early branching of placental
mammals. Only two herpesviruses from Afrotheria have been previously
identified, and the genus Proboscivirus in the subfamily Betaherpesvirinae
has been proposed for them. Six novel gammaherpesviruses were identified
in four species in the superorder Afrotheria by detection and analysis of
their DNA polymerase genes. Elephantid herpesvirus 3 (ElHV3) and
Elephantid herpesvirus 4 (ElHV4) were identified from conjunctival swabs
from Asian elephants (Elephas maximus). ElHV3 was also found
in a vaginal swab from one elephant with vaginitis. Elephantid herpesvirus
5 (ElHV5) was identified from vaginal swabs of two Asian elephants with
vaginal plaques. Elephantid herpesvirus 6 was discovered in a conjunctival
swab from an African elephant (Loxodonta africana). Procavid herpesvirus 1
(PrHV1) was found in spleen and conjunctival swabs of rock hyrax (Procavia
capensis). Trichechid herpesvirus 1 (TrHV1) was identified from skin and
buffy coats of Florida manatees (Trichechus manatus latirostris). ElHV3
and ElHV4 form a distinct cluster, and ElHV5, ElHV6, TrHV1, and PrHV1 form
a second cluster. These viruses may have codiverged with their host
species. Phylogenetic analysis of these novel herpesviruses suggests that
two separate groups of gammaherpesviruses may have codiverged with the
Afrotheria.
Archie, E.A.,
Moss, C.J., Alberts, S.C., 2006. The ties that bind: genetic relatedness
predicts the fission and fusion of social groups in wild African elephants
490. Proc. Biol. Sci. 273, 513-522.
Abstract: Many social animals live in stable groups. In contrast, African
savannah elephants (Loxodonta africana) live in unusually fluid,
fission-fusion societies. That is, 'core' social groups are composed of
predictable sets of individuals; however, over the course of hours or
days, these groups may temporarily divide and reunite, or they may fuse
with other social groups to form much larger social units. Here, we test
the hypothesis that genetic relatedness predicts patterns of group fission
and fusion among wild, female African elephants. Our study of a single
Kenyan population spans 236 individuals in 45 core social groups,
genotyped at 11 microsatellite and one mitochondrial DNA (mtDNA) locus. We
found that genetic relatedness predicted group fission; adult females
remained with their first order maternal relatives when core groups
fissioned temporarily. Relatedness also predicted temporary fusion between
social groups; core groups were more likely to fuse with each other when
the oldest females in each group were genetic relatives. Groups that
shared mtDNA haplotypes were also significantly more likely to fuse than
groups that did not share mtDNA. Our results suggest that associations
between core social groups persist for decades after the original maternal
kin have died. We discuss these results in the context of kin selection
and its possible role in the evolution of elephant sociality
Ball, R.L.,
Dumonceaux, G., Olsen, J.H., Burton, M.S., Lyashchenko, K. Comparison of
trunk wash results matched to multiantigen print immunoassay (MAPIA) in a
group of captive Asian elephants (Elephas maximus). 2006 Proceedings
American Association of Zoo Veterinarians. 303-304. 2006.
Ref Type: Conference Proceeding
Abstract: Introduction: Between 1994 and June 2005, there were 34
confirmed cases of tuberculosis in elephants in the U.S. population.
Thirty-one Asian (Elephas maximus) and three African (Loxodonta africana)
elephants were affected. Mycobacterium tuberculosis was the etiologic
agent in 33 cases and M. bovis in one case. Cases of tuberculosis caused
by an unusual nontuberculous mycobacteria, M. szulgai have recently
occurred as well. Currently, TB in elephants remains a diagnostic
dilemma. The sensitivity of trunk wash culture, the currently recommended
test for diagnosis, is unknown. False negatives have been documented
(trunk wash negative elephants that were subsequently found to be culture
positive at necropsy). Other non-culture techniques for TB diagnosis
include ELISA, and PCR. A novel technology, MultiAntigen Print ImmunoAssay
(MAPIA) and lateral-flow technology (Rapid Test) has been evaluated and
used to diagnose tuberculosis in captive elephants with encouraging
results. One concern with this serologic testing is the possibility of
Mycobacterium other than tuberculosis (MOTT) cross-reacting with the
antigen used in the Rapid Test or the MAPIA and leading to a false
positive. With numerous MOTT routinely cultured from trunk washes, this
is a valid concern. Methods and Materials: A retrospective analysis was
done at Busch Gardens Tampa Bay and Chembio, Inc. that matched trunk wash
results to serum samples. All serum was collected within 7 days of the
trunk wash and analyzed with the Rapid Test and MAPIA. Four Asian
elephants with a total of 18 samples met this criteria and had serum
submitted for testing. Results and Discussion: Table 1 lists the results
and the organisms cultured. While the sampling is limited in this pilot
project, it appears that MOTT does not evoke a response when assayed with
the Rapid Test or MAPIA. The recent cases of M. szulgai do demonstrate the
potential usefulness for this test when a disease develops from MOTT. The
usefulness of this new technology, taken in conjunction with other
clinical data including trunk washes when indicated, is a valuable tool in
the healthcare of captive elephants.
LITERATURE CITED
1 Lacasse, C., K.C. Gamble, K. Terio, L.L. Farina, D.A. Travis, and
M.Miller. 2005. Mycobacterium szulgai osteroarthritis and pneumonia in an
African elephant (Loxdonta africana). Proc. Am. Assoc. Zoo Vet. Ann. Meet.
Pp. 170-172.
2 Larsen, R.S., M.D. Salman, S.K. Mikota, R. Isaza, R.J. Montali, and J.
Triantis. 2000. Evaluation of a multiple-antigen enzyme-linked
immunosorbent assay for detection of Mycobacterium tuberculosis infection
in captive elephants. J. Zoo Wildl. Med. 31:291-302.
3 Lyashchenko, K., et al. 2000. A multiantigen print immunoassay for the
serological diagnosis of infectious diseases. J. Immunol. Methods
242:91-100
4 Lyashchenko, K., M. Miller, and W.R. Waters. 2005. Application of
multiple antigen print immunoassay and rapid lateral flow technology for
tuberculosis testing of elephants. Proc. Am. Assoc. Zoo Vet. Ann. Meet.
Pp. 64-65
Bojesen, A.M.,
Olsen, K.E., Bertelsen, M.F., 2006. Fatal enterocolitis in Asian elephants
(Elephas maximus) caused by Clostridium difficile. Vet Microbiol Epub
ahead of print.
Abstract: Two cases of fatal enteritis caused by Clostridium difficile in
captive Asian elephants are reported from an outbreak affecting five
females in the same zoo. Post mortem examination including histopathology
demonstrated fibrinonecrotic enterocolitis. C. difficile was isolated by
selective cultivation from two dead and a third severely affected
elephant. Four isolates were obtained and found positive for toxin A and B
by PCR. All isolates were positive in a toxigenic culture assay and toxin
was demonstrated in the intestinal content from one of the fatal cases and
in a surviving but severely affected elephant. PCR ribotyping demonstrated
that the C. difficile isolates shared an identical profile, which was
different from an epidemiologically unrelated strain, indicating that the
outbreak was caused by the same C. difficile clone. It is speculated that
the feeding of large quantities of broccoli, a rich source of sulforaphane,
which has been shown to inhibit the growth of many intestinal
microorganisms may have triggered a subsequent overgrowth by C. difficile.
This is the first report of C. difficile as the main cause of fatal
enterocolitis in elephants. The findings emphasize the need to regard this
organism as potentially dangerous for elephants and caution is recommended
concerning antibiotic treatment and feeding with diets containing
antimicrobials, which may trigger an expansion of a C. difficile
population in the gut.
Bojesen, A.M.,
Olsen, K.E., Bertelsen, M.F., 2006. Fatal enterocolitis in Asian elephants
(Elephas maximus) caused by Clostridium difficile
456. Vet. Microbiol. 116, 329-335.
Abstract: Two cases of fatal enteritis caused by Clostridium difficile in
captive Asian elephants are reported from an outbreak affecting five
females in the same zoo. Post mortem examination including histopathology
demonstrated fibrinonecrotic enterocolitis. C. difficile was isolated by
selective cultivation from two dead and a third severely affected
elephant. Four isolates were obtained and found positive for toxin A and B
by PCR. All isolates were positive in a toxigenic culture assay and toxin
was demonstrated in the intestinal content from one of the fatal cases and
in a surviving but severely affected elephant. PCR ribotyping demonstrated
that the C. difficile isolates shared an identical profile, which was
different from an epidemiologically unrelated strain, indicating that the
outbreak was caused by the same C. difficile clone. It is speculated that
the feeding of large quantities of broccoli, a rich source of sulforaphane,
which has been shown to inhibit the growth of many intestinal
microorganisms may have triggered a subsequent overgrowth by C. difficile.
This is the first report of C. difficile as the main cause of fatal
enterocolitis in elephants. The findings emphasize the need to regard this
organism as potentially dangerous for elephants and caution is recommended
concerning antibiotic treatment and feeding with diets containing
antimicrobials, which may trigger an expansion of a C. difficile
population in the gut
Capelli, C.,
MacPhee, R.D., Roca, A.L., Brisighelli, F., Georgiadis, N., O'Brien, S.J.,
Greenwood, A.D., 2006. A nuclear DNA phylogeny of the woolly mammoth (Mammuthus
primigenius)
468. Mol. Phylogenet. Evol. 40, 620-627.
Cooper, A.,
2006. The year of the mammoth. PLoS Biology 4, 1-3.
Abstract: Mammoth mitochondrial (mt) genomes are apparently on a similar
schedule to London buses-you wait for ages and then suddenly three come
along at once. Within the past six weeks, three studies [1-3] have
independently determined all, or most, of the mammoth mt genome sequence,
some 16,800 base pairs (bp). Encouragingly, the partial sequence was a
byproduct of a study that generated some 13 million bp of mammoth genomic
DNA using a new, massively parallel sequencing approach. The very
divergent methods used in these three studies also neatly represent the
past, present, and future of ancient DNA (aDNA) research. aDNA methods
provide an opportunity to characterise the genetic composition of species
and populations in the past, and to actually observe evolutionary change
through real time. Such a record has great potential to reveal the
processes that have generated the diversity and distribution of taxa in
our modern environment, and to examine phenomena such as speciation,
domestication, morphological evolution, and the impacts of major
environmental changes. aDNA data also provide an important opportunity to
test our ability to accurately reconstruct evolutionary history via the
fossil record or via extrapolation from the genetic data of modern
species. Unfortunately, the potential of aDNA remains largely untapped
because research has been severely limited by the technical diffi culties
of retrieving and studying the trace amounts of highly fragmented DNA
that survive in ancient specimens.
Eckhart, L.,
Uthman, A., Sipos, W., Tschachler, E., 2006. Genome sequence comparison
reveals independent inactivation of the caspase-15 gene in different
evolutionary lineages of mammals
428. Molecular Biology and Evolution 23, 2081-2089.
Abstract: We have recently demonstrated that placental mammalian species
such as pig and dog express a novel proapoptotic protease, caspase-15,
whereas mouse and humans lack this enzyme. Here we investigated the
evolutionary fate of the caspase-15 gene in different mammalian lineages
by analyzing whole-genome shotgun sequences of 30 mammalian species for
the presence of caspase-15 orthologs. Caspase-15 gene sequences were found
in representatives of all major mammalian clades except for the
superorders Afrotheria (tenrec, rock hyrax, and elephant) and
Euarchontoglires (rodents, rabbit, tree shrew, and primates), which either
lacked any caspase-15-like sequences or contained mutated remnants of the
caspase-15 gene. Polymerase chain reaction screenings confirmed the
results of the database searches and showed that the caspase-15 gene is
expressed not only in various placental mammals but also in the marsupial,
Monodelphis domestica. The observed species distribution implies that
caspase-15 has originated in an early ancestor of modern mammals and has
been conserved, over more than 180 Myr, in marsupials and many placental
mammals, whereas it was independently lost in 2 phylogenetically distant
clades of placental mammals, that is, Afrotheria and Euarchontoglires. Our
data suggest that the inactivation of the caspase-15 gene was not
counteracted by, and may even have been driven by, evolutionary
constraints in these clades, and therefore, caution against the uncritical
use of gene absence for the inference of phylogenetic relationships
Ehlers, B.,
Dural, G., Marschall, M., Schregel, V., Goltz, M., Hentschke, J., 2006.
Endotheliotropic elephant herpesvirus, the first betaherpesvirus with a
thymidine kinase gene
411. Journal of General Virology 87, 2781-2789.
Abstract: Endotheliotropic elephant herpesvirus (elephantid herpesvirus 1;
ElHV-1) is apathogenic for African elephants (Loxodonta africana), but
causes fatal haemorrhagic disease in Asian elephants (Elephas maximus).
This is thought to occur through transmission from African elephants in
places where both species are housed, such as zoological gardens. The
virus has caused considerable losses in North American and European
zoological gardens and thus severely impedes breeding of the endangered
Asian elephant. Previously, the ultrastructural and genetic
characterization of ElHV-1 from a male Asian elephant that died from the
disease at the Berlin zoological gardens in 1998 have been reported. Here,
a partial characterization of the ElHV-1 genome is presented. A 60 kbp
locus, spanning 34 open reading frames, was analysed. Most of the detected
genes were found to be conserved among the herpesviruses and showed an
overall arrangement most similar to that of betaherpesviruses, in
particular Human herpesvirus 6 and Human herpesvirus 7. Most importantly,
in addition to a protein kinase gene that is homologous to the human
cytomegalovirus UL97 gene, a thymidine kinase (TK) gene was found, which
is generally missing in betaherpesvirus genomes. Thus, ElHV-1 is the only
known betaherpesvirus to encode a TK gene. This peculiarity might
contribute to the fulminant pathogenicity of ElHV-1, but also provide a
crucial enzymic activity for developing an efficient antiviral therapy
with currently available nucleoside analogues
Gee, H., 2006.
Evolution: memories of mammoths
505. Nature 439, 673.
Gupta, S.K.,
Thangaraj, K., Singh, L., 2006. A simple and inexpensive molecular method
for sexing and identification of the forensic samples of elephant origin
430. J. Forensic Sci. 51, 805-807.
Abstract: The population of the Asian elephant is being dramatically
reduced due to poaching of the ivory from the male. As poaching occurs in
remote forests, it often takes weeks or longer for it to be discovered and
it is therefore often very difficult to determine the sex of the
decomposed body. Data suggest that in the recent past, over 2000 male
elephants have been poached in South India. We have developed a technique
based on molecular markers to determine that the carcass is an elephant
and that it is a male. Using DNA sequence information from Genbank, we
have developed two primer pairs: one for the mitochondrial DNA (mtDNA) and
the other for the sex-determining region of Y chromosome (SRY) gene of the
Indian elephant. After PCR amplification of known elephant DNA, we found
that the mtDNA was common in both males and females, whereas the SRY-specific
amplicon was observed only in the male
Hildebrandt,
T.B., Hermes, R., Ratanakorn, P., Rietschel, W., Fickel, J., RetNat, D.,
Frey, R., Reid, C., Goeritz, F. Ultrasonographic assessment and
ultrasound-guided biopsy of the retropharyngeal lymph nodes in elephants.
2006 Proceedings American Association of Zoo Veterinarians. 117-118.
2006.
Ref Type: Conference Proceeding
Abstract: So far there are no valid diagnostic tools available for
identifying latent carriers of endotheliotropic elephant herpes virus (EEHV).
For this reason, the lateral retropharyngeal lymph node complex (LARELYNOC)
of elephants, identified during postmortem studies as target organ for
EEHV and suitable for transcutaneous biopsy, was grossly described.
Transcutaneous ultrasound (3.5 MHz) was applied behind the ear region to
identify the LARELYNOC containing up to four single lymph nodes on each
side. The lymph node tissue is situated 20-50 mm below the skin surface.
An ultrasonographic assessment of the LARELYNOC and two biopsies were
performed on 39 healthy Asian elephants (Elephas maximus). Samples were
tested for EEHV via PCR. Whole blood samples were also collected and
tested for active EEHV infection. Lymph nodes were ultrasonographically
classified as active (calculated mean volume=17.4 ± 6.9 cm3, P>0.001),
inactive (calculated mean volume=3.1 ± 0.6 cm3, P<0.001), or chronic
active (calculated mean volume=10.6 ± 1.0 cm3, P<0.05). Histology
confirmed not only the presence of lymph tissue but also the
ultrasonographically diagnosed reactivity status of the lymph node
biospies. Although all samples including whole blood were found to be
negative for the EEHV DNA particles, the successful development of this
procedure in elephants could prove beneficial for the screening of not
only latent EEHV infections but might also be a less dangerous alternative
method for the diagnosis of zoonotic infections such as tuberculosis.
Hofreiter, M.,
Lister, A., 2006. Mammoths
459. Curr. Biol. 16, R347-R348.
Kitakado, T.,
Kitada, S., Kishino, H., Skaug, H.J., 2006. An integrated-likelihood
method for estimating genetic differentiation between populations
453. Genetics 173, 2073-2082.
Abstract: The aim of this article is to develop an integrated-likelihood
(IL) approach to estimate the genetic differentiation between populations.
The conventional maximum-likelihood (ML) and pseudolikelihood (PL) methods
that use sample counts of alleles may cause severe underestimations of FST,
which means overestimations of theta=4Nm, when the number of sampling
localities is small. To reduce such bias in the estimation of genetic
differentiation, we propose an IL method in which the mean allele
frequencies over populations are regarded as nuisance parameters and are
eliminated by integration. To maximize the IL function, we have developed
two algorithms, a Monte Carlo EM algorithm and a Laplace approximation.
Our simulation studies show that the method proposed here outperforms the
conventional ML and PL methods in terms of unbiasedness and precision. The
IL method was applied to real data for Pacific herring and African
elephants
Krause, J.,
Dear, P.H., Pollack, J.L., Slatkin, M., Spriggs, H., Barnes, I., Lister,
A.M., Ebersberger, I., Paabo, S., Hofreiter, M., 2006. Multiplex
amplification of the mammoth mitochondrial genome and the evolution of
Elephantidae
533. Nature 439, 724-727.
Abstract: In studying the genomes of extinct species, two principal
limitations are typically the small quantities of endogenous ancient DNA
and its degraded condition, even though products of up to 1,600 base pairs
(bp) have been amplified in rare cases. Using small overlapping polymerase
chain reaction products, longer stretches of sequences or even whole
mitochondrial genomes can be reconstructed, but this approach is limited
by the number of amplifications that can be performed from rare samples.
Thus, even from well-studied Pleistocene species such as mammoths, ground
sloths and cave bears, no DNA sequences of more than about 1,000 bp have
been reconstructed. Here we report the complete mitochondrial genome
sequence of the Pleistocene woolly mammoth Mammuthus primigenius. We used
about 200 mg of bone and a new approach that allows the simultaneous
retrieval of multiple sequences from small amounts of degraded DNA. Our
phylogenetic analyses show that the mammoth was more closely related to
the Asian than to the African elephant. However, the divergence of
mammoth, African and Asian elephants occurred over a short time,
corresponding to only about 7% of the total length of the phylogenetic
tree for the three evolutionary lineages
Perelygin, A.A.,
Lear, T.L., Zharkikh, A.A., Brinton, M.A., 2006. Comparative analysis of
vertebrate EIF2AK2 (PKR) genes and assignment of the equine gene to
ECA15q24-q25 and the bovine gene to BTA11q12-q15
416. Genet. Sel Evol. 38, 551-563.
Abstract: The structures of the canine, rabbit, bovine and equine EIF2AK2
genes were determined. Each of these genes has a 5' non-coding exon as
well as 15 coding exons. All of the canine, bovine and equine EIF2AK2
introns have consensus donor and acceptor splice sites. In the equine
EIF2AK2 gene, a unique single nucleotide polymorphism that encoded a
Tyr329Cys substitution was detected. Regulatory elements predicted in the
promoter region were conserved in ungulates, primates, rodents, Afrotheria
(elephant) and Insectifora (shrew). Western clawed frog and fugu EIF2AK2
gene sequences were detected in the USCS Genome Browser and compared to
those of other vertebrate EIF2AK2 genes. A comparison of EIF2AK2 protein
domains in vertebrates indicates that the kinase catalytic domains were
evolutionarily more conserved than the nucleic acid-binding motifs.
Nucleotide substitution rates were uniform among the vertebrate sequences
with the exception of the zebrafish and goldfish EIF2AK2 genes, which
showed substitution rates about 20% higher than those of other
vertebrates. FISH was used to physically assign the horse and cattle genes
to chromosome locations, ECA15q24-q25 and BTA11q12-15, respectively.
Comparative mapping data confirmed conservation of synteny between
ungulates, humans and rodents
Poinar, H.N.,
Schwarz, C., Qi, J., Shapiro, B., MacPhee, R.D., Buigues, B., Tikhonov,
A., Huson, D.H., Tomsho, L.P., Auch, A., Rampp, M., Miller, W., Schuster,
S.C., 2006. Metagenomics to paleogenomics: large-scale sequencing of
mammoth DNA
529. Science 311, 392-394.
Abstract: We sequenced 28 million base pairs of DNA in a metagenomics
approach, using a woolly mammoth (Mammuthus primigenius) sample from
Siberia. As a result of exceptional sample preservation and the use of a
recently developed emulsion polymerase chain reaction and pyrosequencing
technique, 13 million base pairs (45.4%) of the sequencing reads were
identified as mammoth DNA. Sequence identity between our data and African
elephant (Loxodonta africana) was 98.55%, consistent with a
paleontologically based divergence date of 5 to 6 million years. The
sample includes a surprisingly small diversity of environmental DNAs. The
high percentage of endogenous DNA recoverable from this single mammoth
would allow for completion of its genome, unleashing the field of
paleogenomics
Poulakakis, N.,
Parmakelis, A., Lymberakis, P., Mylonas, M., Zouros, E., Reese, D.S.,
Glaberman, S., Caccone, A., 2006. Ancient DNA forces reconsideration of
evolutionary history of Mediterranean pygmy elephantids. Biol. Lett. 2,
451-454.
Abstract: During the Pleistocene pygmy elephantids, some only a quarter of
their ancestors' size, were present on Mediterranean islands until about
10,000 years ago (y.a.). Using a new methodology for ancient DNA (aDNA)
studies, the whole genomic multiple displacement amplification method, we
were able to retrieve cytochrome b (cytb) DNA fragments from 4200 to
800,000 y.a. specimens from island and mainland samples, including pygmy
and normal-sized forms. The short DNA sequence (43 bp) retrieved from the
800,000 y.a. sample is one of the oldest DNA fragment ever retrieved.
Duplication of the experiments in two laboratories, the occurrence of
three diagnostic sites and the results of the phylogenetic analyses
strongly support its authenticity. Our results challenge the prevailing
view that pygmy elephantids of the eastern Mediterranean originated
exclusively from Elephas, suggesting independent histories of dwarfism and
the presence of both pygmy mammoths and elephant-like taxa on these
islands. Based on our molecular data, the origin of the Tilos and Cyprus
elephantids from a lineage within the genus Elephas is confirmed, while
the DNA sequence from the Cretan sample falls clearly within the mammoth
clade. Thus, the name Mammuthus creticus rather than Elephas creticus,
seems to be justified for this form. Our findings also suggest a need to
re-evaluate the evolutionary history of the Sicilian/Maltese species,
traditionally included in the genus Elephas
Reid, C.E.,
Hildebrandt, T.B., Marx, N., Hunt, M., Thy, N., Reynes, J.M., Schaftenaar,
W., Fickel, J., 2006. Endotheliotropic elephant herpes virus (EEHV)
infection. The first PCR-confirmed fatal case in Asia
436. Vet. Q. 28, 61-64.
Abstract: Since 1995, 4 suspected cases of Endotheliotropic Elephant
Herpes Virus (EEHV) infection, i.e. based on clinical presentation, have
occurred in Asia without resulting in epidemic outbreaks as expected. In
order to confirm the presence of EEHV on the continent of Asia, viral DNA
particles from liver samples of a wild-caught 3-year-old elephant found
dead at a Cambodian elephant sanctuary and clinically diagnosed with EEHV,
were PCR processed using known EEHV strain primers. The presence of EEHV
viral nucleic acids was confirmed and the nucleic acids had a 99% sequence
similarity to the U.S.A strain (gene bank locus: AF117265) and 97%
sequence similarity to the European strain (gene bank locus: AF354746)
assigning this case to the EEHV-1 cluster. More than the confirmation of
EEHV on the continent of Asia, is the phylogenic relationship to the USA
and European strains with no corresponding contact or transport of USA or
European elephants to Asia. Thus, this brings many of the traditional
theories into question. Although almost forgotten, this disease is still
ramped in captive elephant populations worldwide and continues to
devastate particularly the neonatal and weaning-age population. Special
attention and continued research are needed specifically in the area of
basic virology and epidemiology
Rogaev, E.I.,
Moliaka, Y.K., Malyarchuk, B.A., Kondrashov, F.A., Derenko, M.V., Chumakov,
I., Grigorenko, A.P., 2006. Complete mitochondrial genome and phylogeny of
Pleistocene mammoth Mammuthus primigenius
507. PLoS. Biol. 4, e73.
Abstract: Phylogenetic relationships between the extinct woolly mammoth (Mammuthus
primigenius), and the Asian (Elephas maximus) and African savanna
(Loxodonta africana) elephants remain unresolved. Here, we report the
sequence of the complete mitochondrial genome (16,842 base pairs) of a
woolly mammoth extracted from permafrost-preserved remains from the
Pleistocene epoch--the oldest mitochondrial genome sequence determined to
date. We demonstrate that well-preserved mitochondrial genome fragments,
as long as approximately 1,600-1700 base pairs, can be retrieved from
pre-Holocene remains of an extinct species. Phylogenetic reconstruction of
the Elephantinae clade suggests that M. primigenius and E. maximus are
sister species that diverged soon after their common ancestor split from
the L. africana lineage. Low nucleotide diversity found between
independently determined mitochondrial genomic sequences of woolly
mammoths separated geographically and in time suggests that north-eastern
Siberia was occupied by a relatively homogeneous population of M.
primigenius throughout the late Pleistocene
Rompler, H.,
Rohland, N., Lalueza-Fox, C., Willerslev, E., Kuznetsova, T., Rabeder, G.,
Bertranpetit, J., Schoneberg, T., Hofreiter, M., 2006. Nuclear gene
indicates coat-color polymorphism in mammoths
439. Science 313, 62.
Abstract: By amplifying the melanocortin type 1 receptor from the woolly
mammoth, we can report the complete nucleotide sequence of a
nuclear-encoded gene from an extinct species. We found two alleles and
show that one allele produces a functional protein whereas the other one
encodes a protein with strongly reduced activity. This finding suggests
that mammoths may have been polymorphic in coat color, with both dark- and
light-haired individuals co-occurring
Sa-Ardrit, M.,
Saikhun, J., Thongtip, N., Damyang, M., Mahasawangkul, S., Angkawanish,
T., Jansittiwate, S., Faisaikarm, T., Kitiyanant, Y., Pavasuthipaisit, K.,
Pinyopummin, A., 2006. Ultrastructural alterations of frozen-thawed Asian
elephant (Elephas maximus) spermatozoa
491. Int. J. Androl 29, 346-352.
Abstract: Intact plasma and acrosome membranes and functional mitochondria
following cryopreservation are important attributes for the fertilizing
ability of spermatozoa. In the present study, functional and
ultrastructural changes of Asian elephant spermatozoa after
cryopreservation either in TEST + glycerol or HEPT + dimethyl sulphoxide (DMSO)
were evaluated by fluorescent techniques and electron microscopy. Sperm
frozen in TEST + glycerol had higher proportion of sperm with intact
plasma (49.1 +/- 9.2% vs. 30.9 +/- 3.9%) and acrosomal (53.7 +/- 4.9% vs.
35.8 +/- 6.1%) membranes, as well as active mitochondria (57.0 +/- 7.2%
vs. 42.0 +/- 5.0%) than those cryopreserved in HEPT + DMSO. The results
obtained from electron microscopy were similar to those obtained by
fluorescence microscopy. The percentage of normal spermatozoa was higher
when spermatozoa were frozen in TEST + glycerol than those frozen in HEPT
+ DMSO (31.8 +/- 5.6 vs. 28.5 +/- 6.4). The ultrastructural alterations
revealed by transmission electron microscopy could be classified as (i)
distension of plasma membrane, while the acrosome was swollen; (ii)
disruption or loss of plasma membrane, while acrosome was swollen with
distended outer acrosomal membrane; (iii) disruption or loss of plasma and
outer acrosomal membrane with leakage of acrosome content; (iv) extensive
vesiculation of plasma and outer acrosomal membrane and leakage of
acrosome content; (v) a complete loss of both plasma membrane and outer
acrosomal membrane; and (vi) swelling of mitochondria. These findings
suggest that the freezing and thawing procedure caused structural damage
to elephant spermatozoa, especially in the plasma membrane, acrosome and
mitochondria. Fluorescence and electron microscopic evaluations are
potentially a powerful tool in the analysis of elephant spermatozoa after
freezing and thawing
Shoshani, J.,
Walter, R.C., Abraha, M., Berhe, S., Tassy, P., Sanders, W.J., Marchant,
G.H., Libsekal, Y., Ghirmai, T., Zinner, D., 2006. A proboscidean from the
late Oligocene of Eritrea, a "missing link" between early Elephantiformes
and Elephantimorpha, and biogeographic implications
384. Proc. Natl. Acad. Sci. U. S. A 103, 17296-17301.
Abstract: We report on a late Oligocene proboscidean species from Eritrea,
dated to 26.8 +/- 1.5 Mya. This "missing link" between early
elephantiformes and Elephantimorpha is the oldest known nongomphothere
proboscidean to probably display horizontal tooth displacement, typical of
elephants [Elephantimorpha consists of Mammutida (mastodons) and
Elephantida, and Elephantida includes gomphotheres, stegodons, and
elephants]. Together with the newly discovered late Oligocene gomphotheres
from Chilga, Ethiopia, the Eritrean taxon points to the importance of East
Africa as a major area for the knowledge of the early evolution of
Elephantimorpha before the faunal exchange between Eurasia and Africa
Thitaram, C.,
Thongtip, N., Somgird, C., Colenbrander, B., Van Boxtel, D.C.J., Lenstra,
J.A. Molecular tool for genetic management and parentage test to control
poaching in Asian elephants. Proceedings International Elephant
Conservation & Research Symposium. 205-209. 2006.
Ref Type: Conference Proceeding
Vidya, T.N.C.,
Sukumar, R. Social organization of the Asian elephant (Elephas maximus) in
southern India as inferred from microsatellite DNA. Proceedings
International Elephant Conservation & Research Symposium. 214-216. 2006.
2006.
Ref Type: Conference Proceeding
Zuba, J.R.,
Oosterhuis, J.E., Pessier, A.P. The toenail "abscess" in elephants:
treatment options including cryotherapy and pathologic similarities with
equine proliferative pododermatitis (canker). 2006 Proceedings American
Association of Zoo Veterinarians. 187-190. 2006.
Ref Type: Conference Proceeding
Abstract: Foot problems potentially represent the single most important
clinical disease of captive elephants. Predisposing factors include
obesity, lack of exercise, nail or sole overgrowth, improper foot care,
poor hygiene, inappropriate enclosure surfaces, poor conformation,
malnutrition and secondary skeletal disorders such as degenerative joint
disease. Furthermore, factors such as elephant management philosophy,
disposition of elephants, facilities and competency of staff in caring for
elephant feet will contribute significantly to the foot health of captive
animals. It is important to note that these conditions are rarely
reported in free-ranging elephants. The elephant toenail abscess is
characterized grossly by proliferative outgrowth of "crab meat-like"
tissue that may acutely rupture through the surface of the nail wall
and/or adjacent cuticle or sole. True abscess formation with localized
collections of suppurative material is not a consistent clinical feature.
In most cases, the inciting cause of these lesions are typically not found
and are likely due to one or more of the predisposing factors listed
above. Once established, these frustrating lesions require extensive,
intensive and prolonged medical attention. If not cared for properly,
these wounds may progress to phalangeal osteomyelitis and the need for
surgical intervention. Sole abscesses are equally frustrating and
difficult to manage with proposed etiologies similar to toenail lesions.
There are no reports in the literature describing the pathology of the
classic proliferative abscess tissue of the elephant nail abscess.
Although variously interpreted as fibrous or granulation tissue, the
authors are unaware of previous histologic descriptions of this tissue.
Biopsy samples of toenail abscess tissue from two Asian elephants (Elephas
maximus) at the San Diego Wild Animal Park (SDWAP) consisted of stratified
squamous epithelium arranged in columns resembling horn tubules. The
predominant histologic finding was marked, near diffuse, hydropic
degeneration of keratinocytes. There were multifocal areas of suppurative
inflammation with admixed bacterial colonies. Inflammatory foci comprised
only a small portion of the lesion and were interpreted as the external
surfaces of the biopsy with likely secondary bacterial colonization.
Because descriptions of the normal histology of the elephant toenail could
not be located, a grossly normal toenail from a different Asian elephant
was obtained to compare histologic features with those of the toenail
abscesses. Sections demonstrated formation of the toenail in a manner
similar to that of the hoof of the horse and cattle with tubular,
intertubular and laminar horn. Primary and secondary epidermal laminae
were identified. Proliferative lesions of horn-producing epithelium
associated with ballooning degeneration and inadequate keratinization of
keratinocytes, have been described in horses as equine "canker" and
coronary band dystrophy. Equine canker is most commonly observed in the
hind feet of draft horses and begins in the frog sometimes with extension
to the sole and hoof wall. Grossly, lesions are characterized by soft
white papillary to "cauliflower-like" tissue associated with a foul odor.
Similar to what is noted in elephant foot problems, predisposing factors
for the development of equine canker include poor hygiene or wet
environmental conditions. There is a lack of gross and histologic
description of the normal nail and sole tissue of the elephant and further
investigations are warranted. A review of the anatomy and histology of
the normal equine hoof may provide a basic understanding of the elephant
nail until more specific and detailed elephant information is available.
From our investigation, the authors offer that a more accurate description
of the elephant toenail abscess would be proliferative pododermatitis, the
term synonymous with equine canker. A more colloquial term such as
"elephant canker" may be appropriate, as well. Canker in the horse is an
uncommon but difficult to treat disease of the hoof. Historically,
treatment options for elephant toenail abscesses include corrective
trimming, superficial debridement and application of topical disinfectants
or antibiotics. Others have constructed innovative sandals to treat and
protect the affected sole or nail with success. The use of regional
intravenous perfusion of the affected limb with antibiotics has also been
successful. Since the elephant nail abscess now appears to be
histologically and clinically comparable to equine canker, this novel
characterization of an old disease may offer unique insight for
treatment. In the least, it has provided our practice with a new list of
treatment options and experienced equine clinicians for consultation who
have been managing patients with a similar disease for many years. One of
the Asian elephants at the SDWAP has had chronic toenail abscesses for
over 2 yr. Radiographs of the affected digits, as reported by others to
assess degree of involvement, have fortunately been negative for evidence
of osteomyelitis. Several bacterial and fungal cultures of deep tissue
biopsies and swabs of affected lesions have resulted in a mixture of
organisms with no consistent single etiologic agent. Biopsies were found
negative for presence of viral DNA (elephant papillomavirus and
herpesvirus) by PCR. Typical elephant foot care at the SDWAP includes
trimming and debriding with hoof knives, foot soaks and topical
antibiotics. Although difficult, attempts are made in keeping the
affected foot clean and dry. Following recommendations for the treatment
of equine canker, we recently implemented the routine use of cryotherapy
in all elephants with proliferative pododermatitis with improved success
in the control and recession of exuberant nail lesions. The proliferative
tissue of the nail is first cleaned then disinfected, debrided, trimmed
with hoof knives and allowed to dry. Modified brass branding tools with
contact surfaces of variable size (2-5 cm diameter) and shape (round or
ovoid) are placed into liquid nitrogen (-196 C) for several minutes and
then placed directly on the cankerous tissue for 30-60 sec. This process
is then repeated 4-5 min later, following a complete thaw of tissue.
Within 24 hr, the cryoburned tissue becomes macerated and necrotic and is
readily removed with gentle scrubbing. Cryotherapy offers the advantage
of destroying tissue to a deeper level than trimming alone and provides
hemostasis, as well. Because of decreased sensation at the cryotherapy
treatment site, a memorable painful event is avoided and the elephant
patient is more routinely accepting of this technique. With the use of
hoof knives, we typically remove 2-3 mm of proliferative tissue before the
patient refuses further treatment, presumably due to discomfort. With
cryotherapy, we are able to remove an additional 3-5 mm of tissue by cell
freezing and necrosis. The result is quicker resolution of cankerous
lesions without the need for aggressive, and potentially painful,
interventions. In conclusion, it appears that elephant nail abscesses can
best be described as proliferative pododermatitis, or canker, as is seen
in other species. Further gross and microscopic descriptions of normal
and pathologic nail or sole lesions are necessary. Routine cryotherapy
has shown promise in the treatment of these chronic, frustrating and
potentially devastating lesions of our captive elephants.
Bertelsen, M.F.,
Bojesen, M., Olsen, K.E.P. Fatal enterocolitis in two Asian elephants (Elephas
maximus) caused by Clostridium difficile. 2005 Proceedings AAZV,
AAWV, AZA Nutrition Advisory Group. 66-67. 2005.
Ref Type: Conference Proceeding
Abstract: Altered behavior, anorexia and listlessness were observed in
four of five adult captive female Asian elephants (Elephas maximus).
Two animals recovered, while two died after 2 days. The dead elephants
were subjected to post mortem examination including histopathology,
demonstrating fibrinonecrotic enteritis and colitis. Clostridium
difficile was isolated from both dead elephants and from the feces of
the two surviving affected animals, and identified by selective
cultivation and PCR identification. All isolates had the tcdA and
tcdB toxin genes and were positive in a toxigenic culture assay.
C. difficile toxin from the intestinal content of one of the fatal
cases was demonstrated using cell-culture based cytotoxin assays.
Clostridium perfringens type A and Clostridium septicum were
also isolated from both dead animals. Although C. perfringens has
been associated with ulcerative enteritis in an elephant,1 in
this case these isolates likely are incidental, as C. perfringens
enterotoxin was not demonstrated, and as C. septicum is well
known for producing rapid post mortem overgrowth. Amplified fragment
length polymorphism typing, showed that the C. difficile isolates
recovered from the outbreak, all had the same fingerprint profile,
indicating that all four elephants were affected by the same bacterial
clone. These findings appear to be the first to demonstrate that C.
difficile may cause enterocolitis in elephants. The results
emphasize the need to regard this organism as potentially dangerous for
elephants. Although there was no prior exposure to antibiotic agents in
this case, caution is recommended when treating elephants with
antibiotics, as this may trigger C. difficile induced
enterocolitis in other species, most notably humans and horses.2
LITERATURE CITED
1 Bacciarini, L.N., O. Pagan, J. Frey, and A. Grone. 2001. Clostridium
perfringens beta2-toxin in an African elephant (Loxodonta africana)
with ulcerative enteritis. Vet. Rec. 149: 618-20.
2 Songer, J.G. 1996. Clostridial enteric diseases of domestic animals.
Clin. Microbiol. Rev. 9: 216-234.
Debruyne, R.,
2005. A case study of apparent conflict between molecular phylogenies: the
interrelationships of African elephants. Cladistics 21, 31-50.
Abstract: Recent molecular phylogenies of the African elephants suggest
that there is an evolutionary structure within Loxodonta africana.
Some nuclear results (Roca et al., 2001) support the separation of the
forest African elephant subspecies L. a. cyclotis as a species
distinct from the savannah elephant L. a. africana, on the basis of
the recognition of both forming highly divergent (reciprocally
monophyletic) clades. Conversely, a mitochondrial survey (Eggert et al.,
2002), while admitting a geographic partitioning of the genetic structure
within African elephants, suggests retaining the status quo. They
recognize three diagnosible entities (western, central and south-eastern
Africa) with non-overlapping ranges within L. africana sensu lato.
In order to address these con.icting views (historical fragmentation and
speciation or isolation by distance, respectively), we have sequenced two
datasets of 1961 bp (for 50 elephants) and about 3700 bp, respectively
(for 20 elephants) of the mitochondrial DNA for both forms of elephants (cyclotis
and africana). They span the cytochrome b gene, the control region and
several RNAs. When compared with former mtDNA data, they provide the most
comprehensive view of the African elephant phylogeny (78 mtDNA haplotypes,
of which 44 are new) and provide the .rst insight into populations from
the Democratic Republic of Congo. The genetic diversity of mtDNA was
appraised and the stability of alternative phylogenetic trees was
investigated. Our results are inconsistent with both those prior studies.
They revealed two highly divergent molecular clades referred to as F and
S, that do not conform to the morphological delineations of cyclotis
and africana. A non-negligible proportion of specimens of L. a.
africana display haplotypes prevailing in forest elephant populations
(clade F). The geographic distribution of clades and areas of their
co-occurrence support the hypothesis of incomplete isolation between
forest and savannah African elephant populations, followed by recurrent
interbreeding between the two forms. We state that the conclusions of
prior studies resulted from insufficient character and / or geographic
sampling. We conclude that there is no satisfying argument which can
recognize two or more species of African elephants. We briefly comment on
the meaning of such an attitude in a conservation viewpoint.
Gibbons, A.,
2005. Ancient DNA. New methods yield mammoth samples
527. Science 310, 1889.
Glickman, S.E.,
Short, R.V., Renfree, M.B., 2005. Sexual differentiation in three
unconventional mammals: spotted hyenas, elephants and tammar wallabies
566. Horm. Behav. 48, 403-417.
Abstract: The present review explores sexual differentiation in three
non-conventional species: the spotted hyena, the elephant and the tammar
wallaby, selected because of the natural challenges they present for
contemporary understanding of sexual differentiation. According to the
prevailing view of mammalian sexual differentiation, originally proposed
by Alfred Jost, secretion of androgen and anti-Mullerian hormone (AMH) by
the fetal testes during critical stages of development accounts for the
full range of sexually dimorphic urogenital traits observed at birth.
Jost's concept was subsequently expanded to encompass sexual
differentiation of the brain and behavior. Although the central focus of
this review involves urogenital development, we assume that the novel
mechanisms described in this article have potentially significant
implications for sexual differentiation of brain and behavior, a
transposition with precedent in the history of this field. Contrary to the
"specific" requirements of Jost's formulation, female spotted hyenas and
elephants initially develop male-type external genitalia prior to gonadal
differentiation. In addition, the administration of anti-androgens to
pregnant female spotted hyenas does not prevent the formation of a
scrotum, pseudoscrotum, penis or penile clitoris in the offspring of
treated females, although it is not yet clear whether the creation of
masculine genitalia involves other steroids or whether there is a genetic
mechanism bypassing a hormonal mediator. Wallabies, where sexual
differentiation occurs in the pouch after birth, provide the most
conclusive evidence for direct genetic control of sexual dimorphism, with
the scrotum developing only in males and the pouch and mammary glands only
in females, before differentiation of the gonads. The development of the
pouch and mammary gland in females and the scrotum in males is controlled
by genes on the X chromosome. In keeping with the "expanded" version of
Jost's formulation, secretion of androgens by the fetal testes provides
the best current account of a broad array of sex differences in
reproductive morphology and endocrinology of the spotted hyena, and
androgens are essential for development of the prostate and penis of the
wallaby. But the essential circulating androgen in the male wallaby is
5alpha androstanediol, locally converted in target tissues to DHT, while
in the pregnant female hyena, androstenedione, secreted by the maternal
ovary, is converted by the placenta to testosterone (and estradiol) and
transferred to the developing fetus. Testicular testosterone certainly
seems to be responsible for the behavioral phenomenon of musth in male
elephants. Both spotted hyenas and elephants display matrilineal social
organization, and, in both species, female genital morphology requires
feminine cooperation for successful copulation. We conclude that not all
aspects of sexual differentiation have been delegated to testicular
hormones in these mammals. In addition, we suggest that research on
urogenital development in these non-traditional species directs attention
to processes that may well be operating during the sexual differentiation
of morphology and behavior in more common laboratory mammals, albeit in
less dramatic fashion
Hildebrandt,
T.B., Hermes, R., Ratanakorn, P., Rietschel, W., Fickel, J., Frey, R.,
Wibbelt, G., Reid, C., Goritz, F., 2005. Ultrasonographic assessment and
ultrasound-guided biopsy of the retropharyngeal lymph nodes in Asian
elephants (Elephas maximus)
552. Veterinary Record 157, 544-548.
Abstract: Endotheliotropic herpesvirus causes a fatal disease in young
Asian elephants, but there are no methods for identifying latent carriers
of the virus. During the postmortem study of one female African elephant
and three male and two female Asian elephants, a lymph node located
bilaterally caudoventral to the parotid gland, approximately 1.5 to 5 cm
below the skin, was identified as suitable for transcutaneous
ultrasound-guided biopsy. An ultrasonographic assessment and two biopsies
were performed on 39 Asian elephants, and these lymph nodes were
classified ultrasonographically as active, inactive or chronically active.
The calculated mean (se) volume of 10 active lymph nodes was 17.4 (6.9)
cm(3), and that of three chronically active lymph nodes was 10.6 (1.0)
cm(3), whereas the mean volume of 17 inactive lymph nodes was 3.1 (0.6)
cm(3). The presence of lymph node tissue in samples obtained by
ultrasound-guided biopsy from three animals that were maintained under
conditions that allowed for additional sampling was confirmed
histologically. The dna extracted from the lymphoid tissue and the whole
blood of all the elephants was negative for endotheliotropic herpesvirus
by PCR.
Lacasse, C.,
Gamble, K.C., Terio, K., Farina, L.L., Travis, D.A., Miller, M.
Mycobacterium szulgai osteoarthritis and pneumonia in an African
elephant (Loxodonta Africana). 2005 Proceedings AAZV, AAWV, AZA
Nutrition Advisory Group. 170-172. 2005.
Ref Type: Conference Proceeding
Abstract: Tuberculosis, particularly Mycobacterium bovis and M.
tuberculosis, is an important health issue in zoological collections.
Zoos are a particular public health concern because of the close contact
between tuberculosis-susceptible animals and humans, specifically animal
handlers and visitors.16 Evidence of M. tuberculosis
transmission between humans and elephants, confirmed by DNA
fingerprinting, has been reported.13 Between 1994 and 2001,
M. tuberculosis was isolated from trunk washes of captive elephants
from 11 herds in the United States.17 To date, most reported
cases of tuberculosis have occurred in captive Asian elephants (Elephas
maximus).14 In 1997, the National Tuberculosis Working
Group for Zoo and Wildlife Species partnered with the USDA to formulate
the "Guidelines for the Control of Tuberculosis in Elephants." 15
This document outlines criteria for the testing, surveillance, and
treatment of tuberculosis in elephants. The guidelines recommend annual
monitoring of elephants by mycobacterial culture of three direct trunk
washes collected over 1 wk. Isolation of Mycobacterium avium and
non-tuberculous mycobacteria from elephant trunk wash samples is common,
but these organisms have not been associated with clinical disease.14,18
This case report details clinical disease with fatal complications of an
atypical mycobacterial infection in an African elephant (Loxodonta
africana). In September 2003, an African elephant presented with
acute, severe lameness of the left rear limb with subsequent swelling of
the stifle. Diagnostic procedures included aspiration cytology of the
swelling, radiographs, and thermographic imaging. The exact location of
the injury could not be detected, but a lesion to the stifle or
coxofemoral articulation was suspected. After 13 mo of treatment,
including pulse therapy with a variety of nonsteroidal anti-inflammatory
drugs (NSAIDs), weekly to biweekly injections of polysulfated
glycosaminoglycan, and intensive foot care efforts to treat secondary
pedal lesions of both rearlimbs, the animal died acutely. Gross necropsy
revealed granulomatous osteomyelitis with necrosis/loss of the femoral
head and acetabulum and pulmonary granulomas. Both of these lesions
contained acid-fast bacteria on cytology. While awaiting confirmatory
culture results, quarantine procedures were established for the elephant
facility and a program was established to screen all zoo personnel in
close contact with the elephant or who participated in the necropsy. All
personnel were tested by the Chicago Department of Public Health without
documented conversion. Mycobacterium szulgai was ultimately
cultured from both coxofemoral and pulmonary lesions. Mycobacterium
szulgai is an uncommon nontuberculous mycobacterium that is usually
isolated from pathologic lesions in humans.21 This bacterial
species was first identified in 1972.11 The lungs are the main
locality for pathologic manifestation in humans and several cases have
been in patients with acquired immunodeficiency syndrome.9,20,21
Infection due to M. szulgai most frequently produces thin-walled
cavities in lungs resembling tuberculosis.4 Other documented
sites of infection include the skin, bone, and tendon sheath (causing a
carpal tunnel syndrome).2,9,10,12,19,20 Intra-operative
contamination from ice water has led to M. szulgai keratitis after
laser-assisted ophthalmic surgeries.6 A case of disseminated
disease in a previously healthy young human has been reported.5
No evidence of human-to-human transmission of this organism has been
documented and human cases are believed to originate from environmental
sources.12 The natural habitat of the organism is unknown, but
previous reports suggest an association of the bacteria with water of
swimming pools and fish tanks.1,21 The organism has been
cultured from a snail and tropical fish.1,3 No standard
recommendation for the treatment of M. szulgai infection currently
exists. In general, triple antibiotic therapies used in standard
mycobacterial treatments are reported with a low rate of relapses and
sterilization of sputum cultures within a mean of 3 mo.3
Pulmonary lesions in this elephant were chronic; it was not possible to
determine when initial infection occurred. Infection could have occurred
in captivity or in the wild prior to captivity. Three trunk washes over
the past year had been negative for mycobacterial culture. Osteomyelitis
in the hip may have developed secondary to hematogenous spread from the
lungs with the acute lameness resulting from a pathologic fracture
associated with this infection. Alternatively, though considered less
likely, a traumatic fracture of the hip could have occurred, with
bacterial inoculation and secondary osteomyelitis as a result of increased
blood flow to the site. The source of infection for this elephant remains
unknown. Prevalence of this organism in the natural habitat or captive
environment of the elephants has not been previously documented.
LITERATURE CITED
1 Abalain-Colloc, M.L., D. Guillerm, M. Salaun, S. Gouriou, V. Vincent,
and B. Picard. 2003. Mycobacterium szulgai isolated from a
patient, a tropical fish, and aquarium water. Eur. J. Clin. Microbiol.
Infect. Dis. 22: 768-769.
2.Cross, G.M., M. Guill, and J.K. Aton. 1985. Cutaneous Mycobacterium
szulgai infection. Arch. Dermatol. 121: 247-249.
3. Davidson, P.T. 1976. Mycobacterium szulgai: a new pathogen
causing infection of the lung. Chest 69: 799- 801.
4. Dylewski, J.S., H.M. Zackon, A.H. Latour, and G.R. Berry. 1987.
Mycobacterium szulgai: an unusual pathogen. Rev. Infect. Dis. 9:
578-580.
5. Gur, H., S. Porat, H. Haas, Y. Naparstek, and M. Eliakim. 1984.
Disseminated mycobacterial disease caused by Mycobacterium szulgai.
Arch. Intern. Med. 144: 1861-1863.
6.Holmes, G.P., G. Bond, R.C. Fader, and S.F. Fulcher. 2002. A cluster of
cases of Mycobacterium szulgai keratitis that occurred after
laser-assisted in situ keratomileusis. Clin. Infect. Dis. 34: 1039-1046.
7.Horusitzky, A., X. Puechal, D. Dumont, T. Begue, M. Robineau, and M.
Boissier. 2000. Carpal tunnel syndrome caused by Mycobacterium
szulgai. J. Rheumatol 27: 1299-1302.
8.Hurr, H., and T. Sorg. 1998. Mycobacterium szulgai
osteomyelitis. J. Infect. 37: 191-192.
9.Luque, A.E., D. Kaminski, R. Reichman, and D. Hardy. 1998.
Mycobacterium szulgai osteomyelitis in an AIDS patient. Scand. J.
Infect. Dis. 30: 88-91.
10.Maloney, J.M., C.R. Gregg, D.S. Stephens, F.A. Manian, and D. Rimland.
1987. Infections caused by Mycobacterium szulgai in humans. Rev.
Infect. Dis. 9: 1120-1126.
11.Marks, J., P.A. Jenkins, and M. Tsukamura. 1972. Mycobacterium
szulgai: a new pathogen. Tubercle 53: 210.
12.Merlet, C., S. Aberrane, F. Chilot, and J. Laroche. 2000. Carpal
tunnel syndrome complicating hand flexor tenosynovitis due to
Mycobacterium szulgai. Joint Bone Spine 67: 247-248.
13.Michalak, K., C. Austin, S. Diesel, J.M. Bacon, P. Zimmerman, and J. N.
Maslow. 1998. Mycobacterium tuberculosis infection as a zoonotic
disease: transmission between humans and elephants. Emerg. Infect. Dis. 4:
283-287.
14.Mikota, S.K., R.S. Larsen, and R.J. Montali. 2000. Tuberculosis in
elephants in North America. Zoo Biol. 19: 393-403.
15.National Tuberculosis Working Group for Zoo and Wildlife Species. 2000.
Guidelines for the control of tuberculosis in elephants. USDA Animal and
Plant Health Inspection Services.
16.Oh, P., R. Granich, J. Scott, B. Sun, M. Joseph, C. Stringfield, S.
Thisdell, J. Staley, D. Workman-Malcolm, L. Borenstein, E. Lehnkering, P.
Ryan, J. Soukup, A. Nitta, and J. Flood. 2002. Human exposure following
Mycobacterium tuberculosis infection of multiple animal species in
a metropolitan zoo. Emerg. Infect. Dis. 8: 1290-1293.
17.Payeur, J.B., J.L. Jarnagin, J.G. Marquardt, and D.L. Whipple. 2002.
Mycobacterial isolations in captive elephants in the United States. Ann.
N.Y. Acad. Sci. 969: 256-258.
18.Shojaei, H., J.G. Magee, R. Freeman, M. Yates, N.U. Horadagoda, and M.
Goodfellow. 2000. Mycobacterium elephantis sp. nov., a rapidly
growing non-chromogenic Mycobacterium isolated from an elephant.
Int. J. Syst. Evol. Microbiol. 50: 1817-1820.
19.Stratton, C.W., D.B. Phelps, and L.B. Reller. 1978. Tuberculoid
tenosynovitis and carpal tunnel syndrome caused by Mycobacterium
szulgai. Am. J. Med. 65: 349-351.
20.Tappe, D., P. Langmann, M. Zilly, H. Klinker, B. Schmausser, and M.
Frosch. 2004. Osteomyelitis and skin ulcers caused by Mycobacterium
szulgai in an AIDS patient. Scand. J. Infect. Dis. 36: 883-885.
21.Tortoli, E., G. Besozzi, C. Lacchini, V. Penati, M.T. Simonetti, and S.
Emler. 1998. Pulmonary infection due to Mycobacterium szulgai,
case report and review of the literature. Eur. Respir. J. 11: 975-977.
Nishihara, H.,
Satta, Y., Nikaido, M., Thewissen, J.G., Stanhope, M.J., Okada, N., 2005.
A retroposon analysis of Afrotherian phylogeny
600. Molecular Biology and Evolution 22, 1823-1833.
Abstract: Recent comprehensive studies of DNA sequences support the
monophyly of Afrotheria, comprising elephants, sirenians (dugongs and
manatees), hyraxes, tenrecs, golden moles, aardvarks, and elephant shrews,
as well as that of Paenungulata, comprising elephants, sirenians, and
hyraxes. However, phylogenetic relationships among paenungulates, as well
as among nonpaenungulates, have remained ambiguous. Here we applied an
extensive retroposon analysis to these problems to support the monophyly
of aardvarks, tenrecs, and golden moles, with elephant shrews as their
sister group. Regarding phylogenetic relationships in Paenungulata, we
could characterize only one informative locus, although we could isolate
many insertions specific to each of three lineages, namely, Proboscidea,
Sirenia, and Hyracoidea. These data prompted us to reexamine phylogenetic
relationships among Paenungulata using 19 nuclear gene sequences resulting
in three different analyses, namely, short interspersed element (SINE)
insertions, nuclear sequence analyses, and morphological cladistics,
supporting different respective phylogenies. We concluded that these three
lineages diverged very rapidly in a very short evolutionary period, with
the consequence that ancestral polymorphism present in the last common
ancestor of Paenungulata results in such incongruence. Our results suggest
the rapid fixation of many large-scale morphological synapomorphies for
Tethytheria; implications of this in relation to the morphological
evolution in Paenungulata are discussed
Okello, J.B.,
Wittemyer, G., Rasmussen, H.B., Douglas-Hamilton, I., Nyakaana, S.,
Arctander, P., Siegismund, H.R., 2005. Noninvasive genotyping and
Mendelian analysis of microsatellites in African savannah elephants. J.
Hered. 96, 679-687.
Abstract: We obtained fresh dung samples from 202 (133 mother-offspring
pairs) savannah elephants (Loxodonta africana) in Samburu, Kenya, and
genotyped them at 20 microsatellite loci to assess genotyping success and
errors. A total of 98.6% consensus genotypes was successfully obtained,
with allelic dropout and false allele rates at 1.6% (n = 46) and 0.9% (n =
37) of heterozygous and total consensus genotypes, respectively, and an
overall genotyping error rate of 2.5% based on repeat typing. Mendelian
analysis revealed consistent inheritance in all but 38 allelic pairs from
mother-offspring, giving an average mismatch error rate of 2.06%, a
possible result of null alleles, mutations, genotyping errors, or
inaccuracy in maternity assignment. We detected no evidence for large
allele dropout, stuttering, or scoring error in the dataset and
significant Hardy-Weinberg deviations at only two loci due to
heterozygosity deficiency. Across loci, null allele frequencies were low
(range: 0.000-0.042) and below the 0.20 threshold that would significantly
bias individual-based studies. The high genotyping success and low errors
observed in this study demonstrate reliability of the method employed and
underscore the application of simple pedigrees in noninvasive studies.
Since none of the sires were included in this study, the error rates
presented are just estimates
Raubenheimer,
E.J., Ngwenya, S.P., 2005. The role of ivory in the survival of the
African elephant
510. SADJ. 60, 426, 430.
Abstract: The unique chequered pattern of polished ivory has created a
perverted commercial demand for elephant tusks. The morphologic basis of
the pattern, which makes ivory a sought after product for the
manufacturing of works of art, is discussed. Chemical analyses of ivory
holds great potential in tracing the source of illegally harvested tusks
and exposing poorly managed elephant sanctuaries. The impact of
uncontrolled ivory hunting on the population genetics of the African
elephant is briefly reviewed
Roca, A.L.,
Georgiadis, N., O'Brien, S.J., 2005. Cytonuclear genomic dissociation in
African elephant species
650. Nat. Genet. 37 , 96-100.
Abstract: African forest and savanna elephants are distinct species
separated by a hybrid zone. Because hybridization can affect the
systematic and conservation status of populations, we examined gene flow
between forest and savanna elephants at 21 African locations. We detected
cytonuclear dissociation, indicative of different evolutionary histories
for nuclear and mitochondrial genomes. Both paternally (n = 205 males) and
biparentally (n = 2,123 X-chromosome segments) inherited gene sequences
indicated that there was deep genetic separation between forest and
savanna elephants. Yet in some savanna locales distant from present-day
forest habitats, many individuals with savanna-specific nuclear genotypes
carried maternally transmitted forest elephant mitochondrial DNA. This
extreme cytonuclear dissociation implies that there were ancient episodes
of hybridization between forest females and savanna males, which are
larger and reproductively dominant to forest or hybrid males. Recurrent
backcrossing of female hybrids to savanna bulls replaced the forest
nuclear genome. The persistence of residual forest elephant mitochondria
in savanna elephant herds renders evolutionary interpretations based on
mitochondrial DNA alone misleading and preserves a genomic record of
ancient habitat changes.
Roca, A.L.,
O'Brien, S.J., 2005. Genomic inferences from Afrotheria and the evolution
of elephants
558. Curr. Opin. Genet. Dev. 15, 652-659.
Abstract: Recent genetic studies have established that African forest and
savanna elephants are distinct species with dissociated cytonuclear
genomic patterns, and have identified Asian elephants from Borneo and
Sumatra as conservation priorities. Representative of Afrotheria, a
superordinal clade encompassing six eutherian orders, the African savanna
elephant was among the first mammals chosen for whole-genome sequencing to
provide a comparative understanding of the human genome. Elephants have
large and complex brains and display advanced levels of social structure,
communication, learning and intelligence. The elephant genome sequence
might prove useful for comparative genomic studies of these advanced
traits, which have appeared independently in only three mammalian orders:
primates, cetaceans and proboscideans
Saragusty, J.,
Hildebrandt, T.B., Natan, Y., Hermes, R., Yavin, S., Goeritz, F., Arav,
A., 2005. Effect of egg-phosphatidylcholine on the chilling sensitivity
and lipid phase transition of Asian elephant (Elephas maximus)
spermatozoa. Zoo Biology 24, 233-245.
Abstract: This study was conducted in an effort to improve our
understanding of the response of Asian elephant (Elephas maximus,
Em) spermatozoa to chilling. Semen was collected from two elephant bulls
by means of the manual rectal stimulation method. Five out of seven semen
collections were deemed to be suitable for use based on motility (ranging
from 20% to 60%) and membrane integrity. We evaluated the chilling
sensitivity by incubating the sperm with a fluorescent dye
(5-carboxyfluorescein diacetate (cFDA)) at 16 degrees C, 12 degrees C, 4
degrees C, and 22 degrees C (control). Cells with an intact membrane
retained the dye and were identified as viable. The membrane lipid phase
transition (LPT) temperature curve was determined with a Fourier transform
infrared (FTIR) spectrometer connected to an FTIR microscope. The LPT
center, T-m, was determined by statistical analysis. The LPT and T-m were
also assessed in fresh spermatozoa and spermatozoa incubated with egg yolk
or egg-phosphatidylcholine (EPC) liposomes at 16 degrees C, 12 degrees C,
4 degrees C, and 26 degrees C (control). The results show that the
membrane integrity of spermatozoa incubated at 16 degrees C, 12 degrees C,
and 4 degrees C decreased by 39%, 62%, and 67%, respectively, compared to
the control. The LPT temperatures were between room temperature (26
degrees C) and 10 degrees C, with Tm at 14-16 degrees C. The T-m for sperm
incubated with liposomes or egg-yolk extender was below the measured range
(2 degrees C). Chilling sensitivity was found at a wide range of
temperatures and transition temperatures, suggesting the presence of a
wide variety of fatty acids (FAs) in the membrane with a high ratio of
saturated-to-polyunsaturated FAs. Here we show that the protection
afforded by the presence of egg yolk or liposomes in the extender is
accomplished by shifting the T. to below the 4 degrees C point at which
chilled semen is maintained for transport, or the point at which fast
freezing begins to minimize cellular damage.
Steinetz, B.G.,
Brown, J.L., Roth, T.L., Czekala, N., 2005. Relaxin concentrations in
serum and urine of endangered species: correlations with physiologic
events and use as a marker of pregnancy
596. Ann. N. Y. Acad. Sci. 1041, 367-378.
Abstract: Many mammalian species are facing extinction due to problems
created by human encroachment, agriculture, pollution, and willful
slaughter. Among those at risk are the Asian and African elephant,
Sumatran rhinoceros, and giant panda. Conservation groups try to save
species in the wild by preserving habitat and limiting animal-human
conflicts, often with limited success. Another alternative is to preserve
the extant gene pool through captive breeding as a hedge against
extinction. Measurement of circulating reproductive hormones is
impractical for most wildlife species; determination of urinary or fecal
hormone metabolites provides a more viable approach. To aid breeding
management, one important tool is the ability to diagnose and monitor
pregnancy, especially in species with long gestations (e.g., rhinos over
15 mo and elephants over 20 mo). Unfortunately, measuring progestins often
is not useful diagnostically, because concentrations are similar during at
least part of the pregnancy and the nonpregnant luteal phase in some
species (e.g., elephants, rhinoceroses, and giant pandas). As serum
relaxin reliably distinguishes between pregnancy and pseudopregnancy in
bitches, relaxin measurement might also provide a method for detecting a
successful pregnancy in endangered species. Appropriate immunoassay
reagents have enabled the estimation of relaxin concentrations in the
serum of elephants and rhinos and the determination of pregnancy
establishment and the outcome. Relaxin was also detected in panda serum
and urine. However, the extreme variability of the time between observed
mating and parturition and the confounding factors of delayed
implantation, pseudopregnancy, and frequent fetal resorptions made it
impossible to use the panda relaxin data as a specific marker of pregnancy
Vidya, T.N.,
Fernando, P., Melnick, D.J., Sukumar, R., 2005. Population differentiation
within and among Asian elephant (Elephas maximus) populations in southern
India
675. Heredity 94, 71-80.
Abstract: Southern India, one of the last strongholds of the endangered
Asian elephant (Elephas maximus), harbours about one-fifth of the global
population. We present here the first population genetic study of
free-ranging Asian elephants, examining within- and among-population
differentiation by analysing mitochondrial DNA (mtDNA) and nuclear
microsatellite DNA differentiation across the Nilgiris-Eastern Ghats,
Anamalai, and Periyar elephant reserves of southern India. Low mtDNA
diversity and 'normal' microsatellite diversity were observed.
Surprisingly, the Nilgiri population, which is the world's single largest
Asian elephant population, had only one mtDNA haplotype and lower
microsatellite diversity than the two other smaller populations examined.
There was almost no mtDNA or microsatellite differentiation among
localities within the Nilgiris, an area of about 15,000 km2. This suggests
extensive gene flow in the past, which is compatible with the home ranges
of several hundred square kilometres of elephants in southern India.
Conversely, the Nilgiri population is genetically distinct at both
mitochondrial and microsatellite markers from the two more southerly
populations, Anamalai and Periyar, which in turn are not genetically
differentiated from each other. The more southerly populations are
separated from the Nilgiris by only a 40-km-wide stretch across a gap in
the Western Ghats mountain range. These results variably indicate the
importance of population bottlenecks, social organization, and
biogeographic barriers in shaping the distribution of genetic variation
among Asian elephant populations in southern India
Vidya, T.N.C.,
Sukumar, K., 2005. Social organization of the Asian elephant (Elephas
maximus) in southern India inferred from microsatellite DNA. J Ethol
23, 205-210.
Abstract: Social organization of the Asian elephant (Elephas maximus)
is not well understood in the absence of long-term studies of
identified individuals. Adult Asian elephant females and their
young offspring of both sexes form matriarchal groups, with
pubertal males dispersing from natal groups, but whether these
social groups represent families and whether males show locational
or social dispersal were unknown. Using nuclear microsatellite loci
amplified from dung-extracted DNA of free-ranging elephants in
a large southern Indian population, we demonstrate that female-led
herds comprise closely related individuals that are indeed
families, and that males exhibit non-random locational dispersal.
Vidya, T.N.C.,
Sukumar, R., 2005. Amplification success and feasibility of using
microsatellite loci amplified from dung to population genetic studies of
the Asian elephant (Elephas maximus). Current Science 88, 489-492.
Abstract: The use of microsatellite DNA markers in large mammal
conservation genetics has been limited by the logistic difficulty in
obtaining optimal sources of DNA from free-ranging animals. Here, we show
high amplification success of microsatellite DNA from elephant dung
samples collected under field conditions. Amplification success depended
on how fresh the sample was when collected, and on the sensitivity of
primers at individual loci. No significant allelic dropout was observed.
We also examined the loci for selective neutrality, independent
inheritance, of loci, and the probability of identity of individuals to
confirm their utility in studies of population genetic structure.
Walker, C.L.,
Stewart, E.A., 2005. Uterine fibroids: the elephant in the room. Science
308, 1589-1592.
Abstract: Uterine fibroids (leiomyomas) have historically been viewed as
important chiefly as the major indication for hysterectomy. As new
therapies are developed, the heterogeneity of this disease becomes
therapeutically relevant. An awareness of the role of genetics, the
extracellular matrix, and hormones in tumor etiology is key to
understanding this disease.
Wooding, F.B.,
Stewart, F., Mathias, S., Allen, W.R., 2005. Placentation in the African
elephant, Loxodonta africanus: III. Ultrastructural and functional
features of the placenta
598. Placenta 26, 449-470.
Abstract: Successful transfer of nutrients to the elephant fetus during
pregnancy relies on a variety of placental modifications. Our light and
electron microscopical investigations show that the structure is
endotheliochorial from implantation to term, with unicellular, never
syncytial trophoblast. Light and electron microscope immunocytochemistry
shows the restriction of the glucose transporter 1 isoform to the
basolateral surfaces of the trophoblast, with the glucose transporter 3
restricted to the apical plasmalemma of the trophoblast. Glucose transport
to the fetus therefore requires a sequential use of both isoforms. Light
and electron microscope cytochemistry indicate the presence of iron
deposits only in the haemophagous zones confirming their iron transport
function. No trophoblast areas with high concentrations of Calcium binding
protein, specialised for Calcium transport were found. In situ
hybridisation demonstrated the presence of IGF-II mRNA in the trophoblast
from the earliest stage, with TGFbeta1 and HGF-SF mRNA expressed
subsequently but only IGF-II and HGF mRNA present in the second half of
pregnancy. The results are briefly discussed in terms of placental growth
and function and indicate that the elephant placenta is another example of
a unique solution to the variety of problems posed by a resident fetus
Yokoyama, S.,
Takenaka, N., Agnew, D.W., Shoshani, J., 2005. Elephants and human
color-blind deuteranopes have identical sets of visual pigments
626. Genetics 170, 335-344.
Abstract: Being the largest land mammals, elephants have very few natural
enemies and are active during both day and night. Compared with those of
diurnal and nocturnal animals, the eyes of elephants and other arrhythmic
species, such as many ungulates and large carnivores, must function in
both the bright light of day and dim light of night. Despite their
fundamental importance, the roles of photosensitive molecules, visual
pigments, in arrhythmic vision are not well understood. Here we report
that elephants (Loxodonta africana and Elephas maximus) use RH1, SWS1, and
LWS pigments, which are maximally sensitive to 496, 419, and 552 nm,
respectively. These light sensitivities are virtually identical to those
of certain "color-blind" people who lack MWS pigments, which are maximally
sensitive to 530 nm. During the day, therefore, elephants seem to have the
dichromatic color vision of deuteranopes. During the night, however, they
are likely to use RH1 and SWS1 pigments and detect light at 420-490 nm
Yokoyama, S.,
Takenaka, N., Agnew, D.W., Shoshani, J., 2005. Elephants and human
color-blind deuteranopes have identical sets of visual pigments. Genetics
170, 335-344.
Abstract: Being the largest land mammals, elephants have very few natural
enemies and are acti ve during both day and night. Compared with those of
diurnal and nocturnal animals, the eyes of elephants and other arrhythmic
species, such as many ungulates and large carnivores, must function in
both the bright light of day and dim light of night. Despite their
fundamental importance, the roles of photosensitive molecules, visual
pigments, in arrhythmic vision are not well understood. Here we report
that elephants (Loxodonta africana and Elephas maximus) use RH1, SWS1, and
LWS pigments, which are maximally sensitive to 496, 419, and 552 nm,
respectively. These light sensitivities are virtually identical to those
of certain "color-blind" people who lack MWS pigments, which are maximally
sensitive to 530 nm. During the day, therefore, elephants seem to have the
dichromatic color vision of deuteranopes. During the night, however, they
are likely to use RH1 and SWS1 pigments and detect light at 420-490 nm.
Agatsuma, T.,
Rajapakse, R.P., Kuruwita, V.Y., Iwagami, M., Rajapakse, R.C., 2004.
Molecular taxonomic position of the elephant schistosome,
Bivitellobilharzia nairi, newly discovered in Sri Lanka
745. Parasitol. Int. 53, 69-75.
Abstract: Bivitellobilharzia nairi (Mudaliar and Ramanujachar, 1945) Dutt
and Srivastava, 1955 was first recorded in India. A number of adult worm
specimens of this schistosome species were recovered from a domestic
elephant, which died in 1999 in Sri Lanka. This is the first report of
this schistosome from Sri Lanka. In the present study, in order to clarify
the phylogenetic relationship with other species of schistosomes,
sequences from the second internal transcribed spacer (ITS2) of the
ribosomal gene repeat, part of the 28S ribosomal RNA gene (28S), and part
of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene from B.
nairi were analyzed. Two intraspecific variations were seen within 13
individuals in the ITS2 region. In the CO1 region of the mitochondrial
DNA, there were four haplotypes in the nucleotide sequences and two
haplotypes in the amino acid sequences. Phylogenetic analysis using the
nuclear DNA showed that B. nairi was basal to all of species of the genus
Schistosoma. The 28S tree also showed that the mammalian lineage was
monophyletic. However, phylogenetic analysis using the mitochondrial DNA
showed that B. nairi was nested within the genus Schistosoma. The
taxonomical position for this species as well as the contradiction between
the results from the nuclear and mitochondrial genes were discussed
Debruyne, R.,
2004. [Contribution of molecular phylogeny and morphometrics to the
systematics of African elephants]
590. J. Soc. Biol. 198, 335-342.
Abstract: African elephants are conventionally classified as a single
species: Loxodonta africana (Blumenbach 1797). However, the discovery in
1900 of a smaller form of the African elephant, spread throughout the
equatorial belt of this land, has given rise to a debate over the
relevance of a second species of elephant in Africa. The twentieth century
has not provided any definite answer to this question. Actually, recent
molecular analyses have sustained this issue by advocating either a
division of forest elephants into a valid species, or their inclusion as a
subspecies of L. africana. Our work initiated at the National Museum of
Natural History of Paris provides new molecular (mitochondrial) and
morphological (and morphometrical) evidence making it possible to propose
a comprehensive phylogenetic hypothesis. It appears that there is no
conclusive argument to keep forest elephants (cyclotis form) and savannah
elephants (africana form) apart in two distinct species. A high level of
mitochondrial introgression between the two forms, as well as a continuum
in the morphology of the skulls of the two morphotypes rather suggests
that, despite an ancient division, these two taxa freely interbreed
wherever their ranges intersect. We thus adopt a conservative systematic
position in considering these two forms as two subspecies, respectively:
L. africana africana, the savannah elephant, and L. africana cyclotis, the
forest elephant. We finally discuss the conservation topic in the light of
this systematic framework
Greenwood,
A.D., Englbrecht, C.C., MacPhee, R.D., 2004. Characterization of an
endogenous retrovirus class in elephants and their relatives
667. BMC. Evol. Biol. 4, 38.
Abstract: BACKGROUND: Endogenous retrovirus-like elements (ERV-Ls, primed
with tRNA leucine) are a diverse group of reiterated sequences related to
foamy viruses and widely distributed among mammals. As shown in previous
investigations, in many primates and rodents this class of elements has
remained transpositionally active, as reflected by increased copy number
and high sequence diversity within and among taxa. RESULTS: Here we
examine whether proviral-like sequences may be suitable molecular probes
for investigating the phylogeny of groups known to have high element
diversity. As a test we characterized ERV-Ls occurring in a sample of
extant members of superorder Uranotheria (Asian and African elephants,
manatees, and hyraxes). The ERV-L complement in this group is even more
diverse than previously suspected, and there is sequence evidence for
active expansion, particularly in elephantids. Many of the elements
characterized have protein coding potential suggestive of activity.
CONCLUSIONS: In general, the evidence supports the hypothesis that the
complement had a single origin within basal Uranotheria
Lazar, J.,
Rasmussen, L.E., Greenwood, D.R., Bang, I.S., Prestwich, G.D., 2004.
Elephant albumin: a multipurpose pheromone shuttle
691. Chem. Biol. 11, 1093-1100.
Abstract: (Z)-7-dodecenyl acetate (Z7-12:Ac) is present in the urine of
female Asian elephants (Elephas maximus) approaching ovulation and
functions as a female-to-male sex pheromone. Here we show that a
significant fraction of the pheromone in the urine is bound to a protein,
elephant serum albumin (ESA), and provide evidence for key physiological
functions of urinary ESA. Our biochemical and behavioral experiments
suggest a three-fold role of ESA in pheromone signaling: (1) transporting
Z7-12:Ac from serum into urine; (2) extending the presence of the
pheromone in the environment without hampering detection; and (3)
targeting pheromone delivery to chemosensory organs through localized
release of the ligand induced by a pH change. The exploitation of albumin
in pheromone transport clearly distinguishes the elephant from other
mammals studied, and complements the uniqueness of elephant anatomy,
physiology, and behavior
Thongtip, N.,
Saikhun, J., Damyang, M., Mahasawangkul, S., Suthunmapinata, P., Yindee,
M., Kongsila, A., Angkawanish, T., Jansittiwate, S., Wongkalasin, W.,
Wajjwalkul, W., Kitiyanant, Y., Pavasuthipaisit, K., Pinyopummin, A.,
2004. Evaluation of post-thaw Asian elephant (Elephas maximus) spermatozoa
using flow cytometry: the effects of extender and cryoprotectant
711. Theriogenology 62, 748-760.
Abstract: Although the development of semen cryopreservation in the
African elephants (Loxodonta africana) has been accomplished, effective
procedures for cryopreservation of Asian elephant (Elephas maximus)
spermatozoa have not been established. In the present study, we
investigate the freezing methods for conservation of Asian elephant
spermatozoa under field conditions and identify the most suitable freezing
protocols which provide acceptable post-thaw semen quality. Semen was
collected from two Asian elephant bulls (EM1 and EM2, 10 ejaculates from
each bull) by manual manipulation and were assessed for volume, pH, sperm
cell concentration, and progressive motility. Eight out of 20 ejaculates
were of acceptable quality (progressive motility >/= 60%), and were used
for cryopreservation studies. Semen were frozen in TEST + glycerol, TEST +
DMSO, HEPT + glycerol, or HEPT + DMSO. The post-thaw progressive sperm
motilities were assessed, and sperm cells were stained with PI and
FITC-PNA for membrane and acrosomal integrity assessment using flow
cytometry. Post-thaw progressive motility of spermatozoa (EM1: 42.0 +/-
4.3%; EM2: 26.0 +/- 17.3%) and the percentage of membrane and acrosome
intact spermatozoa (EM1: 55.5 +/- 8.1%; EM2: 46.3 +/- 6.4%) cryopreserved
in TEST + glycerol were significantly higher than (P < 0.05) those frozen
in the other medium investigated choices for cryopreservation of Asian
elephant spermatozoa. The data support the use of TEST + glycerol as an
acceptable cryopreservation media of Asian elephant semen for the
establishment of sperm banks
Wasser, S.K.,
Shedlock, A.M., Comstock, K., Ostrander, E.A., Mutayoba, B., Stephens, M.,
2004. Assigning African elephant DNA to geographic region of origin:
applications to the ivory trade
673. Proc. Natl. Acad. Sci. U. S. A 101, 14847-14852.
Abstract: Resurgence of illicit trade in African elephant ivory is placing
the elephant at renewed risk. Regulation of this trade could be vastly
improved by the ability to verify the geographic origin of tusks. We
address this need by developing a combined genetic and statistical method
to determine the origin of poached ivory. Our statistical approach
exploits a smoothing method to estimate geographic-specific allele
frequencies over the entire African elephants' range for 16 microsatellite
loci, using 315 tissue and 84 scat samples from forest (Loxodonta africana
cyclotis) and savannah (Loxodonta africana africana) elephants at 28
locations. These geographic-specific allele frequency estimates are used
to infer the geographic origin of DNA samples, such as could be obtained
from tusks of unknown origin. We demonstrate that our method alleviates
several problems associated with standard assignment methods in this
context, and the absolute accuracy of our method is high. Continent-wide,
50% of samples were located within 500 km, and 80% within 932 km of their
actual place of origin. Accuracy varied by region (median accuracies: West
Africa, 135 km; Central Savannah, 286 km; Central Forest, 411 km; South,
535 km; and East, 697 km). In some cases, allele frequencies vary
considerably over small geographic regions, making much finer
discriminations possible and suggesting that resolution could be further
improved by collection of samples from locations not represented in our
study
Archie, E.A.,
Moss, C.J., Alberts, S.C., 2003. Characterization of tetranucleotide
microsatellite loci in the African Savannah Elephant (Loxodonta africana
africana). Molecular Ecology Notes 3, 244-246.
Abstract: Most African elephant (Loxodonta africana africana) populations
are isolated and thus threatened by a loss of genetic diversity. As a
consequence, genetic analysis of African elephant populations will play an
increasing role in their conservation, and microsatellite loci will be an
important tool in these analyses. Previously published sets of polymorphic
microsatellites developed for African elephants are all dinucleotide
repeats, which are prone to typing error. Here, we characterize 11
tetranucleotide microsatellite loci in the African elephant. All loci were
polymorphic in 32 faecal samples and two tissue samples from 33 individual
African savannah elephants. Biology Department, Duke University, Box
90338, Durham, NC 27708, USA; eaa@duke.edu
Debruyne, R.,
Van Holt, A., Barriel, V., Tassy, P., 2003. Status of the so-called
African pygmy elephant (Loxodonta pumilio (NOACK 1906)): phylogeny of
cytochrome b and mitochondrial control region sequences. C R Biol 326,
687-697.
Abstract: Among the African elephants, it has been unanimously
acknowledged that the forest elephants (cyclotis form) are peculiar, so
that they have been elevated to the specific rank. The development of
molecular analyses of extant Loxodonta has only focused on two forms yet:
the savannah form (africana) and the forest form (cyclotis), disregarding
the so-called pygmy elephants (pumilio or fransseni) the systematic status
of which has been debated since their discovery. Therefore, we have
sampled nine dwarfed-labelled specimens in collection and eight specimens
of typical forest elephants that we compared to three savannah elephants
and two Asian elephants. Because of the degraded nature of the nuclear DNA
content in bone samples of old specimens, we assayed mitochondrial
markers; 1961 bp of the mitochondrial genome were sequenced (over a
continuous range spanning the cytochrome b gene, tRNA Thr, tRNA Pro,
hypervariable region 1 and central conserved region of the control
region). Pumilio and cyclotis are not sister-taxa: the phylogenetic
analyses rather account for the inclusion of the so-called pygmy elephants
within a monophyletic group of forest elephants sensu lato. The internal
structure of this clade reveals to depend on isolation and remoteness
between populations, characteristics that may have been extensively
influenced by climatic variations during the Quaternary period. We
conclude that the specific taxon Loxodonta pumilio (or Loxodonta fransseni)
should be abandoned. FR 1541 CNRS, Service de systematique moleculaire,
Museum national d'histoire naturelle, 43, rue Cuvier, 75005 Paris, France.
debruyne@mnhn.fr
Eggert, L.S.,
Eggert, J.A., Woodruff, D.S., 2003. Estimating population sizes for
elusive animals: the forest elephants of Kakum National Park, Ghana. Mol
Ecol 12, 1389-1402.
Abstract: African forest elephants are difficult to observe in the dense
vegetation, and previous studies have relied upon indirect methods to
estimate population sizes. Using multilocus genotyping of noninvasively
collected samples, we performed a genetic survey of the forest elephant
population at Kakum National Park, Ghana. We estimated population size,
sex ratio and genetic variability from our data, then combined this
information with field observations to divide the population into age
groups. Our population size estimate was very close to that obtained using
dung counts, the most commonly used indirect method of estimating the
population sizes of forest elephant populations. As their habitat is
fragmented by expanding human populations, management will be increasingly
important to the persistence of forest elephant populations. The data that
can be obtained from noninvasively collected samples will help managers
plan for the conservation of this keystone species. Ecology, Behavior and
Evolution Section, Division of Biological Sciences, University of
California, San Diego 92093-0116, USA. lori_eggert@hotmail.com
Fernando, P.,
Vidya, T.N., Payne, J., Stuewe, M., Davison, G., Alfred, R.J., Andau, P.,
Bosi, E., Kilbourn, A., Melnick, D.J., 2003. DNA analysis indicates that
Asian elephants are native to Borneo and are therefore a hgh priority for
conservation. PLoS Biol. 1, E6 (Epub 2003 Aug 18).
Abstract: The origin of Borneo's elephants is controversial. Two competing
hypotheses argue that they are either indigenous, tracing back to the
Pleistocene, or were introduced, descending from elephants imported in the
16th-18th centuries. Taxonomically, they have either been classified as a
unique subspecies or placed under the Indian or Sumatran subspecies. If
shown to be a unique indigenous population, this would extend the natural
species range of the Asian elephant by 1300 km, and therefore Borneo
elephants would have much greater conservation importance than if they
were a feral population. We compared DNA of Borneo elephants to that of
elephants from across the range of the Asian elephant, using a fragment of
mitochondrial DNA, including part of the hypervariable d-loop, and five
autosomal microsatellite loci. We find that Borneo's elephants are
genetically distinct, with molecular divergence indicative of a
Pleistocene colonisation of Borneo and subsequent isolation. We reject the
hypothesis that Borneo's elephants were introduced. The genetic divergence
of Borneo elephants warrants their recognition as a separate evolutionary
significant unit. Thus, interbreeding Borneo elephants with those from
other populations would be contraindicated in ex situ conservation, and
their genetic distinctiveness makes them one of the highest priority
populations for Asian elephant conservation. Center for Environmental
Research and Conservation, Columbia University, New York, New York, United
States of America. pf133@columbia.edu
Fernando, P.,
Vidya, T.N., Rajapakse, C., Dangolla, A., Melnick, D.J., : 2003. Reliable
noninvasive genotyping: fantasy or reality? J Hered 94, 115-123.
Abstract: Noninvasive genotyping has not gained wide application, due to
the notion that it is unreliable, and also because remedial measures are
time consuming and expensive. Of the wide variety of noninvasive DNA
sources, dung is the most universal and most widely used in studies. We
have developed collection, extraction, and amplification protocols that
are inexpensive and provide a high level of success in amplifying both
mitochondrial and nuclear DNA from dung. Here we demonstrate the
reliability of genotyping from elephant dung using these protocols by
comparing results from dung-extracted DNA to results from blood-extracted
DNA. The level of error from dung extractions was only slightly higher
than from blood extractions, and conducting two extractions from each
sample and a single amplification from each extraction was sufficient to
eliminate error. Di-, tri-, and tetranucleotide loci were equally
reliable, and low DNA quantity and quality and PCR inhibitors were not a
major problem in genotyping from dung. We discuss the possible causes of
error in genotyping with particular reference to noninvasive samples and
suggest methods of reducing such error. Center for Environmental Research
and Conservation, Columbia University, 1200 Amsterdam Avenue, New York, NY
10027, USA. pf133@columbia.edu
Fronicke, L.,
Wienberg, J., Stone, G., Adams, L., Stanyon, R., 2003. Towards the
delineation of the ancestral eutherian genome organization: comparative
genome maps of human and the African elephant (Loxodonta africana)
generated by chromosome painting. Proc R Soc Lond B Biol Sci. 270,
1331-1340.
Abstract: This study presents a whole-genome comparison of human and a
representative of the Afrotherian clade, the African elephant, generated
by reciprocal Zoo-FISH. An analysis of Afrotheria genomes is of special
interest, because recent DNA sequence comparisons identify them as the
oldest placental mammalian clade. Complete sets of whole-chromosome
specific painting probes for the African elephant and human were
constructed by degenerate oligonucleotide-primed PCR amplification of
flow-sorted chromosomes. Comparative genome maps are presented based on
their hybridization patterns. These maps show that the elephant has a
moderately rearranged chromosome complement when compared to humans. The
human paint probes identified 53 evolutionary conserved segments on the 27
autosomal elephant chromosomes and the X chromosome. Reciprocal
experiments with elephant probes delineated 68 conserved segments in the
human genome. The comparison with a recent aardvark and elephant Zoo-FISH
study delineates new chromosomal traits which link the two Afrotherian
species phylogenetically. In the absence of any morphological evidence the
chromosome painting data offer the first non-DNA sequence support for an
Afrotherian clade. The comparative human and elephant genome maps provide
new insights into the karyotype organization of the proto-afrotherian, the
ancestor of extant placental mammals, which most probably consisted of
2n=46 chromosomes. Erratum in: Proc R Soc Lond B Biol Sci. 2003 Dec
22;270(1533):2639. Comparative Molecular Cytogenetics Section, National
Cancer Institute-Genetics Branch, National Cancer Institute-Frederick,
Nationa Institutes of Health, Building 560, Room 11-75, Frederick, MD
21702-1201, USA. froenickel@gmx.net
Hermes, R.,
Arav, A., Saragusty, J., Goeritz, F., Pettit, M., Blottner, S., Flach, E.,
Eshkar, G., Boardman, W., Hildebrandt, T.B. Cryopreservation of Asian
elephant spermatozoa using directional freezing. Proc.Amer Assoc of Zoo
Veterinarians. 264. 2003.
Ref Type: Conference Proceeding
Abstract: Male infertility and absence of males in a facility are
contributing factors to the limited reproduction of Asian elephants in
captivity. Subsequent transport for breeding purposes increase social
stress, risks of disease transmission and management costs. Recent success
in artificial insemination eliminated these obstacles only transporting
the semen. However, the transport of fresh semen involves logistical<bold>
</bold>difficulties: access to semen donors, consistent semen quality and
preservation of the spermatozoa during transport. The use of cryo-preserved
sperm for AI can partially overcome these problems and can additionally be
used for the establishment of Genome Resource Banks. However, to date,
attempts to cryo-preserve Asian elephant spermatozoa have failed due to
its sensitivity to freezing. Aims of this study were to identify the
temperature range during which spermatozoa is most sensitive to chilling
injury, and to use directional freezing (DF) to reduce cell damage during
the freezing process. Semen was collected from two Asian elephants by
manual stimulation. DF was used for freezing sperm samples. In contrast to
conventional freezing methods DF facilitated a fast cooling rate,
controlled ice crystal formation and cryopreservation of large volumes.
Samples extended with a variety of DMSO extenders showed post thaw
motility of 30-40%. DF was able to cryo-preserve Asian Elephant
spermatozoa for the first time. As DF seems to reduce cryo injury it may
become of interest to optimize existing cryopreservation protocols of
other endangered species, or to make cryopreservation even possible in
species with cryo-sensitive spermatozoa.
Vidya, T.N.C.,
Kumar, V.R., Arivazhagan, C., Sukumar, R., 2003. Application of molecular
sexing to free-ranging Asian elephant (Elephas maximus) populations in
southern India. Current Science 85, 1074-1077.
Abstract: Selective poaching of Asian elephant (Elephas maximus) males for
ivory has resulted in highly female-biased adult sex ratios, necessitating
regular monitoring of population structure and demography. We demonstrate
that molecular sexing from dung-extracted DNA, based on ZFX-ZFY fragment
amplification and ZFY-specific BamHI site restriction, can be applied to
estimate sex ratios of free-ranging Asian elephants, in addition to or
instead of field demographic methods. The adult sex ratios using molecular
sexing in Nagarahole and Mudumalai-Bandipur reserves during May 2001 were
1: 3.1, matching the demography-based sex ratio for the same month, and 1:
9.4, respectively.
Yang, F.,
Alkalaeva, E.Z., Perelman, P.L., Pardini, A.T., Harrison, W.R., O'Brien,
P.C., Fu, B., 2003. Reciprocal chromosome painting among human, aardvark,
and elephant (superorder Afrotheria) reveals the likely eutherian
ancestral karyotype. Proc Natl Acad Sci U S A 100, 1062-1066.
Abstract: The Afrotheria, a supraordinal grouping of mammals whose
radiation is rooted in Africa, is strongly supported by DNA sequence data
but not by their disparate anatomical features. We have used flow-sorted
human, aardvark, and African elephant chromosome painting probes and
applied reciprocal painting schemes to representatives of two of the
Afrotherian orders, the Tubulidentata (aardvark) and Proboscidea
(elephants), in an attempt to shed additional light on the evolutionary
affinities of this enigmatic group of mammals. Although we have not yet
found any unique cytogenetic signatures that support the monophyly of the
Afrotheria, embedded within the aardvark genome we find the strongest
evidence yet of a mammalian ancestral karyotype comprising 2n = 44. This
karyotype includes nine chromosomes that show complete conserved synteny
to those of man, six that show conservation as single chromosome arms or
blocks in the human karyotype but that occur on two different chromosomes
in the ancestor, and seven neighbor-joining combinations (i.e., the
synteny is maintained in the majority of species of the orders studied so
far, but which corresponds to two chromosomes in humans). The comparative
chromosome maps presented between human and these Afrotherian species
provide further insight into mammalian genome organization and comparative
genomic data for the Afrotheria, one of the four major evolutionary clades
postulated for the Eutheria.
Comstock, K.E.,
Georgiadis, N., Pecon-Slattery, J., Roca, A.L., Ostrander, E.A., O'Brien,
S.J., Wasser, S.K., 2002. Patterns of molecular genetic variation among
African elephant populations. Mol Ecol 11, 2489-2498.
Abstract: The highly threatened African elephants have recently been
subdivided into two species, Loxodonta africana (savannah or bush
elephant) and L. cyclotis (forest elephant) based on morphological and
molecular studies. A molecular genetic assessment of 16 microsatellite
loci across 20 populations (189 individuals) affirms species level genetic
differentiation and provides robust genotypic assessment of species
affiliation. Savannah elephant populations show modest levels of
phylogeographic subdivision based on composite microsatellite genotype, an
indication of recent population isolation and restricted gene flow between
locales. The savannah elephants show significantly lower genetic diversity
than forest elephants, probably reflecting a founder effect in the recent
history of the savannah species.
Nyakaana, S.,
Arctander, P., Siegismund, H.R., 2002. Population structure of the African
savannah elephant inferred from mitochondrial control region sequences and
nuclear microsatellite loci. Heredity 89, 90-98.
Abstract: Two hundred and thirty-six mitochondrial DNA nucleotide
sequences were used in combination with polymorphism at four nuclear
microsatellite loci to assess the amount and distribution of genetic
variation within and between African savannah elephants. They were sampled
from 11 localities in eastern, western and southern Africa. In the total
sample, 43 haplotypes were identified and an overall nucleotide diversity
of 2.0% was observed. High levels of polymorphism were also observed at
the microsatellite loci both at the level of number of alleles and gene
diversity. Nine to 14 alleles per locus across populations and 44 alleles
in the total sample were found. The gene diversity ranged from 0.51 to
0.72 in the localities studied. An analysis of molecular variance showed
significant genetic differentiation between populations within regions and
also between regions. The extent of subdivision between populations at the
mtDNA control region was approximately twice as high as shown by the
microsatellite loci (mtDNA F(ST) = 0.59; microsatellite R(ST) = 0.31). We
discuss our results in the light of Pleistocene refugia and attribute the
observed pattern to population divergence in allopatry accompanied by a
recent population admixture following a recent population expansion.
Roca, A.L.,
Georgiadis, N., Pecon-Slattery, J., O'Brien, S.J., 2002. Genetic evidence
for two species of elephant in Africa. Science 293, 1473-1477.
Abstract: Elephants from the tropical forests of Africa are
morphologically distinct from savannah or bush elephants. Dart-biopsy
samples from 195 free-ranging African elephants in 21 populations were
examined for DNA sequence variation in four nuclear genes (1732 base
pairs). Phylogenetic distinctions between African forest elephant and
savannah elephant populations corresponded to 58% of the difference in the
same genes between elephant genera Loxodonta (African) and Elephas
(Asian). Large genetic distance, multiple genetically fixed nucleotide
site differences, morphological and habitat distinctions, and extremely
limited hybridization of gene flow between forest and savannah elephants
support the recognition and conservation management of two African
species: Loxodonta africana and Loxodonta cyclotis.
Vogel, G.,
2002. Ecology. African elephant species splits in two. Science 293,
1414.
Burkhardt, S.,
Goltz, M., Bergmann, V., Ochs, A., Weiler, H., Hentschke, J., 2001.
Genetic and ultrastructural characterization of a European isolate of the
fatal endotheliotropic elephant herpesvirus. Journal of General Virology
82, 475-482.
Abstract: A male Asian elephant (Elephas maximus) died at the Berlin
zoological gardens in August 1998 of systemic infection with the novel
endotheliotropic elephant herpesvirus (EIHV-1). This virus causes a fatal
haemorrhagic disease in Asian elephants, the so-called endothelial
inclusion body disease, as reported from North American zoological
gardens. In the present work, EIHV-1 was visualized ultrastructurally in
affected organ material. Furthermore, a gene block comprising the complete
glycoprotein B (gB) and DNA polymerase (DPOL) genes as well as two partial
genes was amplified by PCR-based genome walking and sequenced. The gene
content and arrangement were similar to those of members of the
Betaherpesvirinae. However, phylogenetic analysis with gB and DPOL
consistently revealed a very distant relationship to the betaherpesviruses.
Therefore, EIHV-1 may be a member of a new genus or even a new herpesvirus
subfamily. The sequence information generated was used to set up a nested-PCR
assay for diagnosis of suspected cases of endothelial inclusion body
disease. Furthermore, it will aid in the development of antibody-based
detection methods and of vaccination strategies against this fatal
herpesvirus infection in the endangered Asian elephant.
Comstock, K.E.,
Ostrander, E.A., Wasser, S.K. A Genetic Method for Determining the
Geographic Origin of Poached African Elephant Ivory. A Research Update on
Elephants and Rhinos; Proceedings of the International Elephant and Rhino
Research Symposium, Vienna, June 7-11, 2001. 256. 2001. Vienna, Austria,
Schuling Verlag. 2001.
Ref Type: Conference Proceeding
Fernando, P.,
Melnick, D.J., 2001. Molecular sexing eutherian mammals. Molecular Ecology
Notes 1, 350-353.
Abstract: Mammals can be molecularly sexed by polymerase chain reaction (PCR)
amplification of Y chromosome fragments or coamplification of homologous
fragments from both sex chromosomes, which are discriminated by size
polymorphism or Y-specific restriction digestion. Although coamplification
of X and Y fragments is more reliable, size polymorphism in homologous
fragments is uncommon and Y-specific restriction site identification
requires screening with a battery of enzymes or cloning. Here we describe
a simple approach, using 'double peaks' in the chromatogram upon direct
sequencing of PCR products from males, to identify Y-specific restriction
sites, and demonstrate its utility by application to a range of taxa. We
demonstrate its utility by application to a range of mammalian taxa;
Probocideans: Asian elephant (Elephas maximus), Perrisodactyls: Indian
rhinoceros (Rhinoceros unicornis), Carnivores: domestic dog (Canis
familiaris) and Primates: Tonkean macaque (Macaca tonkeana).
Fernando, P.,
Vidya, T.N.C., Melnick, D.J., 2001. Isolation and characterization of tri-
and tetranucleotide microsatellite loci in the Asian elephant, Elephas
maximus. Molecular Ecology Notes 1, 232-233.
Abstract: Asian elephants (Elephas maximus) are an endangered species.
Their future survival depends on intensive conservation and management,
based on in-depth knowledge of particular populations. Molecular genetic
methods, especially microsatellite analysis through noninvasive sampling,
provides an effective means of obtaining such information. The use of tri-
and tetranucleotide microsatellite markers is advantageous in noninvasive
sampling through dung analysis. Here we describe the isolation and
characterization of five tri- and tetranucleotide markers in the Asian
elephant. All five loci were found to be polymorphic in a sample of 20
Asian elephants from Sri Lanka.
Fleischer, R.C.,
Perry, E.A., Muralidharan, K., Stevens, E.E., Wemmer, C.M., 2001.
Phylogeography of the Asian elephant (Elephas maximus) based on
mitochondrial DNA. Evolution 55, 1882-1892.
Abstract: Populations of the Asian elephant (Elephas maximus) have been
reduced in size and become highly fragmented during the past 3000 to 4000
years. Historical records reveal elephant dispersal by humans via trade
and war. How have these anthropogenic impacts affected genetic variation
and structure of Asian elephant populations? We sequenced mitochondrial
DNA (mtDNA) to assay genetic variation and phylogeography across much of
the Asian elephant's range. Initially, we compared cytochrome b sequences
(cyt b) between 9 Asian and 5 African elephants and used the fossil-based
age of their separation (_5 million years ago) to obtain a rate of about
0.013 (95% CI=0.011-0.018) corrected sequence divergence per million
years. We also assessed variation in part of the mtDNA control region (CR)
and adjacent tRNA genes in 57 Asian elephants from 7 countries (Sri
Lanka, India, Nepal, Myanmar, Thailand, Malaysia, and Indonesia). Asian
elephants had typical levels of mtDNA variation, and coalescence analyses
suggested their populations were growing in the late Pleistocene.
Reconstructed phylogenies revealed 2 major clades (A and B) differing on
average by HKY85/GAMMA-corrected distances of 0.020 for cyt b and 0.050
for the CR segment (corresponding to a coalescence time based on our cyt b
rate of _1.2 million years). Individuals of both major clades existed in
all locations, but Indonesia and Malaysia. Most elephants from Malaysia
and all from Indonesia were in well-supported, basal clades within clade
A, thus supporting their status as evolutionarily significant units (ESUs).
The proportion of clade A individuals decreased to the north, which could
result from retention and subsequent loss of ancient lineages in long-term
stable populations or, perhaps more likely, via recent mixing of 2
expanding populations that were isolated in the mid-Pleistocene. The
distribution of clade A individuals appeared to be impacted by human trade
in elephants among Myanmar, Sri Lanka, and India, and the subspecies and
ESU statuses of Sri Lankan elephants were not supported by molecular data.
Houck, M.L.,
Kumamoto, A.T., Gallagher, D.S.Jr., Benirschke, K., 2001. Comparative
cytogenetics of the African elephant (Loxodonta africana) and Asiatic
elephant (Elephas maximus). Cytogeneticsand Cell Genetics 93,
249-252.
Abstract: G- and C-banded karyotypes of the two extant species of the
mammalian order Proboscidea are presented for the first time. Chromosome
complements were 2n=56 in both Loxodonta africana and Elephas maximus.
Comparisons between the species demonstrated a high level of chromosome
band homology, with 26 conserved autosomal pairs. The normal diploid
karyotype of L. africana had 25 acrocentric/telocentric and two
metacentric/submetacentric autosomal pairs. E. maximus differed by having
one less acrocentric and one additional submetacentric pair due to either
a heterochromatic arm addition or deletion involving autosomal pair 27.
Several acrocentric autosomes of L. africana exhibited small short arms
that were absent in homologous chromosomes of E. maximus. The X
chromosomes in both species were large submetacentric elements and were
homologous. However, the small acrocentric Y chromosomes differed; in E.
maximus it was slightly larger and had more distinct G-bands than its
counterpart in L. africana. Extant Elephantidae appear to be relatively
conservative in their rates of chromosomal change compared to some other
mammalian families. The high-quality banded karyotypes presented here
should prove useful as references for future chromosome analyses of
elephant populations and in comparative cytogenetic studies with other
ungulate orders.
Muller, S.,
Steinborn, R., Schwammer, H., Muller, M. Molecular Genetic Identification
of Elephant Products. A Research Update on Elephants and Rhinos;
Proceedings of the International Elephant and Rhino Research Symposium,
Vienna, June 7-11, 2001. 277. 2001. Vienna, Austria, Schuling Verlag.
2001.
Ref Type: Conference Proceeding
Murphy, W.J.,
Eizirik, E., Johnson, W.E., Zhang, Y.P., Ryder, O.A., O'Brien, S.J., 2001.
Molecular phylogenetics and the origins of placental mammals. Nature 409,
614-618.
Abstract: The precise hierarchy of ancient divergence events that led to
the present assemblage of modern placental mammals has been an area of
controversy among morphologists, paleontologists and molecular
evolutionists. Here we address the potential weaknesses of limited
character and taxon sampling in a comprehensive molecular phylogenetic
analysis of 64 species sampled across all extant orders of placental
mammals. We examined sequence variation in 18 homologous gene segments
(including nearly 10,000 base pairs) that were selected for maximal
phylogenetic informativeness in resolving the hierarchy of early mammalian
divergence. Phylogenetic analyses identify four primary superordinal
clades: (I) Afrotheria (elephants, manatees, hyraxes, tenrecs, aardvark
and elephant shrews); (II) Xenarthra (sloths, anteaters and armadillos);
(III) Glires (rodents and lagomorphs), as a sister taxon to primates,
flying lemurs and tree shrews; and (IV) the remaining orders of placental
mammals (cetaceans, artiodactyles, perissodactyles, carnivores, pangolins,
bats and core insectivores). Our results provide new insight into the
pattern of the early placental mammal radiation.
Okayama, T.,
Sugardjito, J., Yusuf, I. Mitochondrial DNA Analysis of Sumatran
Elephants. A Research Update on Elephants and Rhinos; Proceedings of the
International Elephant and Rhino Research Symposium, Vienna, June 7-11,
2001. 278-281. 2001. Vienna, Austria, Schuling Verlag. 2001.
Ref Type: Conference Proceeding
Southern, S.
Molecular analysis of stress-activated proteins and genes in dolphins and
whales: a new technique for monitoring environmental stress. Proc AAZV and
AAAM Joint Conference. 240-242. 2001.
Ref Type: Conference Proceeding
Abstract: In the past several decades, there has been a worldwide increase
in marine diseases resulting in mass mortality among all major taxa and
shifts in ecologic community structures in the oceans.1 Marine mammals
have experienced a pandemic of morbilliviral infections and outbreaks of
diseases caused by influenza viruses, fungi and algal toxins. Many of the
disease outbreaks appear to have been facilitated by increased
environmental stress burden in the global marine ecosystems due to
changing environmental conditions triggered by climate variability and
human activities. It is imperative to develop novel health-monitoring
tools that could guide the management of marine ecosystems and facilitate
the conservation of key species. Our research is focused on the molecular
mechanisms underlying molecular stress response in humans and cetaceans
exposed to
environmental stress and disease. We have developed new techniques for
detecting the molecular signature of stress based on molecular analysis of
stress-activated proteins and genes in field tissue specimens.2 The
detection of molecular stress signature has been applied to evaluate the
impact of tuna fishery on the spotted dolphins in the Eastern Tropical
Pacific, the effects of coastal pollution on the beluga whales in the St.
Lawrence River, and the idiopathic population decline of the North
Atlantic right whale population.
Tiedemann, R.,
Kurt, F., Gonnesekere, N., Gunasekera, M., Ratnasooriya, W.D. Population
Dynamics in Wild-Living and Captive Asian Elephants: Demographic and
Genetic Aspects. A Research Update on Elephants and Rhinos; Proceedings of
the International Elephant and Rhino Research Symposium, Vienna, June
7-11, 2001. 140. 2001. Vienna, Austria, Schuling Verlag. 2001.
Ref Type: Conference Proceeding
Whitehouse,
A.M., Harley, E.H. Genetic Diversity and Paternity of the Elephant
Population in Addo Elephant National Park, South Africa. A Research Update
on Elephants and Rhinos; Proceedings of the International Elephant and
Rhino Research Symposium, Vienna, June 7-11, 2001. 146. 2001. Vienna,
Austria, Schuling Verlag. 2001.
Ref Type: Conference Proceeding
Whitehouse,
A.M., Harley, E.H., 2001. Post-bottleneck genetic diversity of elephant
populations in South Africa,revealed using microsatellite analysis. Mol
Ecol 10, 2139-2149.
Abstract: Widespread hunting had fragmented and severely reduced elephant
populations in South Africa by 1900. Elephant numbers increased during the
1900s, although rates of recovery of individual populations varied. The
Kruger National Park elephant population increased rapidly, to more than
6000 by 1967, with recruitment boosted by immigration from Mozambique. The
Addo Elephant National Park population was reduced to 11 elephants in 1931
and remains relatively small (n = 325). Loss of genetic variation is
expected to occur whenever a population goes through a bottleneck,
especially when post-bottleneck recovery is slow. Variation at nine
polymorphic microsatellite loci was analysed for Kruger and Addo
elephants, as well as museum specimens of Addo elephants shot prior to the
population bottleneck. Significantly reduced genetic variation and
heterozygosity were observed in Addo in comparison to Kruger (mean
alleles/locus and H(E): Addo 1.89, 0.18; Kruger 3.89, 0.44). Two alleles
not present in the current Addo population were observed in the museum
specimens. Addo elephants represent a genetic subset of the Kruger
population, with high levels of genetic differentiation resulting from
rapid genetic drift. The Kruger population is low in genetic diversity in
comparison to East African elephants, confirming this population also
suffered an appreciable bottleneck.
Comstock, K.E.,
Wasser, S.K., Ostrander, E.A., 2000. Polymorphic microsatellite DNA loci
identified in the African elephant(Loxodonta africana). Mol Ecol 9,
1004-1006.
Eggert, L.S.,
Ramakrishnan, U., Mundy, N.I., Woodruff, D.S., 2000. Polymorphic
microsatellite DNA markers in the African elephant (Loxodonta africana)
and their use in the Asian elephant (Elephas maximus). Molecular Ecology 9,
2223-2225.
Abstract: Genomic DNA from 4 captive African elephants was pooled and used
to produce a DNA library. The library was screened with 32P-labelled
(CA)15 and (GA)15 probes. 32 microsatellites were detected, 12 of which
were uninterrupted and had sufficient flanking DNA to permit design of PCR
primers. These primers were used on DNA samples from 10 African savannah
elephants from the Frozen Zoo of the Zoological Society of San Diego.
Three primer sets amplified monomorphic sequences, 3 did not give a usable
product. The number of alleles for the other 6 loci ranged from 3 to 11.
The 6 primers that gave polymorphic products were used on samples from 12
Asian elephants from the Frozen Zoo; 1 locus failed to amplify, the others
yielded 2-4 alleles. The primers were also tested on DNA extracted from
dung samples of 86 African forest elephants from Kakum National Park
(Ghana). One set of primers did not amplify a sequence in the forest
elephants, another was monomorphic. The remaining 4 loci had expected
heterozygosities of 0.521 to 0.760 and observed heterozygosities of 0.377
to 0.747. The nucleotide sequences reported have been deposited with the
GenBank database with the accession numbers AF311670-AF311675.
Fernando, P.,
Lande, R., 2000. Molecular genetic and behavioral analysis of social
organization in the Asian elephant (Elephas maximus). Behavioral Ecology
and Sociobiology 48, 84-89.
Abstract: We report on the genetic evaluation and behavioural study of
social organization in the Asian elephant (Elephas maximus). Although
Asian elephants and African elephants (Loxodonta africana) were previously
thought to have similar social organizations, our results demonstrate a
substantial difference in the complexity and structure of Asian elephant
social groupings from that described for African savanna elephants.
Photographic cataloguing of individuals, radio telemetry, and behavioural
observations in Ruhuna National Park, Sri Lanka, enabled us to assign
associated females and young to four groups with overlapping ranges.
Genetic sampling of individuals from the four groups in Ruhuna National
Park and three other groups in surrounding areas, conducted through PCR
amplification and sequencing of mitochondrial DNA from dung, supported the
matriarchal nature of female groups and the lack of inter-group transfer
of females. Behaviourally and genetically, the identified social groups
were best described as "family groups". We did not find any evidence for
the existence of social groups of higher complexity than family groups.
Fernando, P.,
Pfrender, M.E., Encalada, S.E., Lande, R., 2000. Mitochondrial DNA
variation, phylogeography and population structure of the Asian elephant.
Heredity 84, 362-372.
Abstract: We report the first genetic analysis of free-ranging Asian
elephants (Elephas maximus). We sampled 118 elephants from Sri Lanka,
Bhutan/North India, and Laos/Vietnam by extracting DNA from dung, PCR
amplifying and sequencing 630 nucleotides of mtDNA, including part of the
variable left domain of the control region. Comparison with African
elephant (Loxodonta africana) sequences indicated a relatively slow
molecular clock in the Proboscidea with a sequence divergence of
_1%/million years. Genetic diversity within Asian elephants was low,
suggesting a small long-term effective population size. 17 haplotypes were
identified within Asian elephants, which clustered into 2
well-differentiated assemblages with an estimated Pliocene divergence of
2.5-3.5 million years ago. The 2 assemblages showed incomplete
geographical partitioning, suggesting allopatric divergence and secondary
admixture. On the mainland, little genetic differentiation was observed
between elephant populations of Bhutan and India or Laos and Vietnam. A
significant difference in haplotype frequencies but relatively weak
subdivision was observed between the Bhutan-India and Laos-Vietnam
regions. Significant genetic differentiation was observed between the
mainland and Sri Lanka and between northern, mid-latitude and southern
regions in Sri Lanka.
Suwattana, D.,
Koykul, W., Mahasawangkul, S., Kanchanapangka, S., Joerg, H., Stranzinger,
G., 2000. The GTG-banded karyotype and telomere FISH in Asian elephants
(Elephas maximus). Veterinarni Medicina 45, 10-11.
Abstract: Lymphocyte cultures were performed for chromosome preparations
from 70 Asian elephants (Elephas maximus) held captive in the province of
Lampang, Thailand. The elephant karyotype was demonstrated using Giemsa
staining and GTG banding techniques. The diploid number (2n) was 56 or 28
chromosome pairs, consisting of 6 pairs of bi-armed chromosomes and 21
telocentric chromosome pairs. The chromosomes were classified and numbered
according to size, centromere position and banding patterns. Chromosome 1
exhibited a secondary constriction on the proximal third of the p-arm
whereas chromosomes 2- 6 showed faint bands probably due to their
heterochromatic constitution. The X chromosome was medium submetacentric
with distinctive bands while the Y was a small telocentric chromosome with
a dark band around the centromere. An idiogram of a total 216 bands was
established from the GTG-bands which will be useful for physical gene
mapping. Telomeres of the Asian elephant chromosomes were localized using
a fluorescein-conjugated peptide nucleic acid (PNA) probe containing a
telomeric sequence (TTAGGG). Fluorescence in situ hybridization (FISH)
revealed the locations of four spots of telomeres on all chromosomes
including the sex chromosomes. Our observations demonstrated that
telomeric DNA sequences have been well conserved in the Asian elephants
and similar to those shown in almost all vertebrates.
Thomas, M.G.,
Hagelberg, E., Jones, H.B., Yang, Z., Lister, A.M., 2000. Molecular and
morphological evidence on the phylogeny of the Elephantidae. Proceedings
of the Royal Society of London SeriesB, Biological-Sciences 267:1561,
2493-2500.
Abstract: The African and Asian elephants and the mammoth diverged ca. 4-6
million years ago and their phylogenetic relationship has been
controversial. Morphological studies have suggested a mammoth-Asian
elephant relationship, while molecular studies have produced conflicting
results. We obtained cytochrome b sequences of up to 545 base pairs from
five mammoths, 14 Asian and eight African elephants. A high degree of
polymorphism is detected within species. With a dugong sequence used as
the outgroup, parsimony and maximum-likelihood analyses support a
mammoth-African elephant clade. As the dugong is a very distant outgroup,
we employ likelihood analysis to root the tree with a molecular clock, and
use bootstrap and Bayesian analyses to quantify the relative support for
different topologies. The analyses support the mammoth-African elephant
relationship, although other trees cannot be rejected. Ancestral
polymorphisms may have resulted in gene trees differing from the species
phylogeny. Examination of morphological data, especially from primitive
fossil members, indicates that some supposed synapomorphies between the
mammoth and Asian elephant are variable, others convergent or
autapomorphous. A mammoth-African elephant relationship is not excluded.
Our results highlight the need, in both morphological and molecular
phylogenetics, for multiple markers and close attention to within-taxon
variation and outgroup selection.
Tiedemann, R.,
Hardy, O., Vekemans, X., Milinkovitch, M.C., 2000. Higher impact of female
than male migration on population structure in large mammals. Mol Ecol 9,
1159-1163.
Abstract: We simulated large mammal populations using an individual-based
stochastic model under various sex-specific migration schemes and life
history parameters from the blue whale and the Asian elephant. Our model
predicts that genetic structure at nuclear loci is significantly more
influenced by female than by male migration. We identified requisite
comigration of mother and offspring during gravidity and lactation as the
primary cause of this phenomenon. In addition, our model predicts that the
common assumption that geographical patterns of mitochondrial DNA (mtDNA)
could be translated into female migration rates (Nmf) will cause biased
estimates of maternal gene flow when extensive male migration occurs and
male mtDNA haplotypes are included in the analysis.
Greenwood,
A.D., Paabo, S., 1999. Nuclear insertion sequences of mitochondrial DNA
predominate in hair but not in blood of elephants. Molecular Ecology 8,
133-137.
Abstract: It was found that PCR primers that amplified a segment of the
mitochondrial control region from blood samples from African and Asian
elephants mainly amplified integrated nuclear copies of mitochondrial DNA
in hair samples. It is concluded that, in some species under some
circumstances, DNA from hair may yield unreliable results.
Greenwood,
A.D., Capelli, C., Possnert, G., Paabo, S., 1999. Nuclear DNA sequences
from late Pleistocene megafauna. Mol Biol Evol 16, 1466-1473.
Abstract: We report the retrieval and characterization of multi- and
single-copy nuclear DNA sequences from Alaskan and Siberian mammoths (Mammuthus
primigenius). In addition, a nuclear copy of a mitochondrial gene was
recovered. Furthermore, a 13,000-year-old ground sloth and a
33,000-year-old cave bear yielded multicopy nuclear DNA sequences. Thus,
multicopy and single-copy genes can be analyzed from Pleistocene faunal
remains. The results also show that under some circumstances, nucleotide
sequence differences between alleles found within one individual can be
distinguished from DNA sequence variation caused by postmortem DNA damage.
The nuclear sequences retrieved from the mammoths suggest that mammoths
were more similar to Asian elephants than to African elephants.
Holt, W.V.,
Pickard, A.R., 1999. Role of reproductive technologies and genetic
resource banks in animal conservation. Rev Reprod 4, 143-150.
Abstract: In combination with modem reproductive technologies, there is
potential to use frozen and stored germplasm (genetic resource banks) to
support conservation measures for the maintenance of genetic diversity in
threatened species. However, turning this idea into reality is a complex
process, requiring interdisciplinary collaboration and clearly defined
goals. As the number of species deserving the attention of conservation
scientists is overwhelmingly large, yet detailed knowledge of reproductive
physiology is restricted to relatively few of them, choosing which species
to conserve is one of the most difficult issues to be tackled. Besides the
direct application of technologically advanced reproductive procedures,
modern approaches to non-invasive endocrine monitoring play an important
role in optimizing the success of natural breeding programmes. Through the
analysis of urine and faecal samples, this type of technology provides
invaluable management information about the reproductive status of diverse
species. For example, it is possible to diagnose pregnancy and monitor
oestrous cycles in elephants and rhinos without causing stress through
restraint for sample collection. In this review, we identify the potential
contribution of reproductive biology and genetic resource banks to animal
conservation, but also highlight the complexity of issues determining the
extent to which this potential can be achieved.
Nyakaana, S.,
Arctander, P., 1999. Population genetic structure of the African elephant
in Uganda based on variation at mitochondrial and nuclear loci: evidence
for male-biased gene flow. Mol Ecol 8, 1105-1115.
Abstract: A drastic decline has occurred in the size of the Uganda
elephant population in the last 40 years, exacerbated by two main factors;
an increase in the size of the human population and poaching for ivory.
One of the attendant consequences of such a decline is a reduction in the
amount of genetic diversity in the surviving populations due to increased
effects of random genetic drift. Information about the amount of genetic
variation within and between the remaining populations is vital for their
future conservation and management. The genetic structure of the African
elephant in Uganda was examined using nucleotide variation of
mitochondrial control region sequences and four nuclear microsatellite
loci in 72 individuals from three localities. Eleven mitochondrial DNA (mtDNA)
haplotypes were observed, nine of which were geographically localized. We
found significant genetic differentiation between the three populations at
the mitochondrial locus while three out of the four microsatellite loci
differentiated KV and QE, one locus differentiated KV and MF and no loci
differentiated MF and QE. Expected heterozygosity at the four loci varied
between 0.51 and 0.84 while nucleotide diversity at the mitochondrial
locus was 1.4%. Incongruent patterns of genetic variation within and
between populations were revealed by the two genetic systems, and we have
explained these in terms of the differences in the effective population
sizes of the two
genomes and male-biased gene flow between populations.
Waddell, P.J.,
Cao, Y., Hauf, J., Hasegawa, M., 1999. Using novel phylogenetic methods to
evaluate mammalian mtDNA, including amino acid-invariant sites-LogDet plus
site stripping, to detect internal conflicts in the data, with special
reference to the positions of hedgehog, armadillo, and elephant. Syst Biol
48, 31-53.
Abstract: We look at the higher-order phylogeny of mammals, analyzing in
detail the complete mtDNA sequences of more than 40 species. We test the
support for several proposed superordinal relationships. To this end, we
apply a number of recently programmed methods and approaches, plus
better-established methods. New pairwise tests show highly significant
evidence that amino acid frequencies are changing among nearly all the
genomes studied when unvaried sites are ignored. LogDet amino acid
distances, with modifications to take into account invariant sites, are
combined with bootstrapping and the Neighbor Joining algorithm to account
for these violations of standard models. To weight the more slowlyevolving
sites, we exclude the more rapidly evolving sites from the data by using
"site stripping". This leads to changing optimal trees with nearly all
methods. The bootstrap support for many hypotheses varies widely between
methods, and few hypotheses can claim unanimous support from these data.
Rather, we uncover good evidence that many of the earlier branching
patterns in the placental subtree could be incorrect, including the
placement of the root. The tRNA genes, for example, favor a split between
the group hedgehog, rodents, and primates versus all other sequenced
placentals. Such a grouping is not ruled out by the amino acid sequence
data. A grouping of all rodents plus rabbit, the old Glires hypothesis, is
also feasible with stripped amino acid data, and rodent monophyly is also
common. The elephant sequence allows confident rejection of the older
taxon Ferungulata (Simpson, 1945). In its place, the new taxa Scrotifera
and Fereuungulata are defined. A new likelihood ratio test is used to
detect differences between the optimal tree for tRNA versus that for amino
acids. While not clearly significant as made, some results indicate the
test is tending towards significance with more general models of
evolution. Individual placement tests suggest alternative positions for
hedgehog and elephant. Congruence arguments to support elephant and
armadillo together are striking, suggesting a superordinal group composed
of Xenarthra and African endemic mammals, which in turn may be near the
root of the placental subtree. Thus, while casting doubt on some recent
conclusions, the analyses are also unveiling some interesting new
possibilities.
Burk, N.E.,
Messer, L.A., Ernst, C.W., Rothschild, M.F., 1998. Identification of
sequence tagged sites in the Asian and African elephant. Animal
Biotechnology 9, 155-160.
Abstract: PCR was used to identify sequence-tagged sites in Asian and
African elephants. Heterologous primers were designed from sequences
available in other species. Fragments of 141 bp for retinoic acid
receptor-beta and 327 bp for leptin receptor were obtained by amplifying
genomic Asian and African elephant DNA. The leptin receptor fragment
included an intron of 164 bp. A 417 bp fragment for melatonin receptor 1a
was obtained from Asian elephants only. All PCR products were sequenced
and comparison computations were made at the nucleotide and amino acid
levels with sequences available in the GenBank database. The nucleotide
sequences were identical for Asian and African elephants for retinoic acid
receptor-beta and differed by only 3 bp for leptin receptor. Deduced amino
acid sequences were identical for both sequence-tagged sites in the 2
species. The sequences from elephants were relatively similar to those of
other mammals and less similar to those of fowls. The nucleotide sequences
have been deposited in the GenBank database with accession numbers U95047,
U95050 and U95048 for melatonin receptor 1a, retinoic acid receptor-beta
and leptin receptor of Asian elephants and U95051 and U95049 for retinoic
acid receptor beta and leptin receptor of African elephants respectively.
Chen, Y.Z.,
Liu, R.Q., Nai, W.H., Wang, J.H., He, C.H., Bao, Y.F., Lei, W.H., 1998.
The chromosomes of the Asian elephant. Zoological Research 19,
93-94.
Gilmore, J.A.,
McGann, L.E., Ashworth, E., Acker, J.P., Raath, J.P., Bush, M., Critser,
J.K., 1998. Fundamental cryobiology of selected African mammalian
spermatozoa and its role in biodiversity preservation through the
development of genome resource banking. Anim Reprod Sci 53,
277-197.
Abstract: Fundamental cryobiological characteristics of spermatozoa from
threatened or endangered species must be determined for successful
cryopreservation techniques to be established. In this study, spermatozoa
from four diverse species, impala (Aepyceros melampus), wart hog (Phacochoerus
aethiopicus), elephant (Loxodonta africana), and lion (Panthera leo), were
collected by electroejaculation or epididymal aspiration. Spermatozoal
plasma membrane permeability to water (hydraulic conductivity, Lp) and the
osmotically inactive fraction of the sperm cell (Vb) were determined from
each species. Changes in cell volume were measured over time using an
electronic particle counter. A Kedem-Katchalsky membrane transport model
was used to theoretically characterize the data to determine Lp and Vb for
each species. In addition to determining plasma membrane characteristics,
spermatozoa were also studied to determine their sensitivity to low
temperatures and to permeating cryoprotectant solutes. Cells maintained at
room temperature (20-22 degrees C) were slowly or rapidly exposed to cold
temperatures (1-4 degrees C), and percent motility was estimated to
determine the sensitivity of the cells to cooling. Spermatozoa were also
in media containing 1 M glycerol, dimethyl sulfoxide or ethylene glycol,
and percent motility was measured at 15, 30 and 60 min intervals to
determine the sensitivity of the cells to the cryoprotectant agent over
time. Results indicate that sperm motility is significantly effected by
decreased temperatures and the presence of cryoprotectant agents.
Gunasena, K.T.,
Lakey, J.R., Villines, P.M., Bush, M., Raath, C., Critser, E.S., McGann,
L.E., Critser, J.K., 1998. Antral follicles develop in xenografted
cryopreserved African elephant (Loxodonta africana) ovarian tissue. Anim
Reprod Sci 53, 265-275.
Abstract: The preservation of germ plasm from endangered species could
augment captive breeding programs aimed at maintaining genetic diversity.
Mammalian female germ plasm (oocytes) is extremely difficult to collect
and cryopreserve; however, a promising alternative is the cryopreservation
of ovarian tissue. In the present study, athymic nude (nu/nu) Balb/C mice
were used to evaluate in vivo viability of cryopreserved ovarian tissue
from Institute of Cancer Research genotype (ICR) mice or elephants. Female
mice were ovariectomized prior to transplant of cryopreserved-thawed
ovarian tissue from ICR mice (n=4) or elephants (n=6). Control mice were
sham operated (n=4) or ovariectomized (n=5). Transplants were in the
ovarian bursa, enabling in vivo ovulation and pregnancies from allografts.
Vaginal cytology was monitored daily, and the intervals between
andduration of epithelial cells present in smears were evaluated.
Appearance of epithelial cells in sham-operated and allografted mice were
at intervals of 4.3+/-0.6 and 3.3+/-0.5 days, lasting for 1.4+/-0.1 and
1.6+/-0.2 days, respectively. Sporadic incidence of epithelial cells in
ovariectomized animals occurred at longer intervals (8.6+/-3.8 days).
Females with xenografted elephant ovarian tissue demonstrated epithelial
cells in vaginal smears at intervals of 4.5+/-1.0 days, for 2.5+/-0.5 days
duration, which was significantly longer than the other groups (P < 0.05).
Histological evaluation of tissues at the time of epithelial cells in
smears demonstrated well-developed antral follicles, although oocytes were
of poor morphological appearance or only cumulus-like complexes were seen.
The nude mouse model is effective for assessing cryopreserved ovarian
tissue xenograft function which can support the development of antral
follicles.
Noro, M.,
Masuda, R., Dubrovo, I.A., Yoshida, M.C., Kato, M., 1998. Molecular
phylogenetic inference of the woolly mammoth Mammuthus primigenius, based
on complete sequences of mitochondrial cytochrome b and 12S ribosomal RNA
genes. J Mol Evol 46, 314-326.
Abstract: Complete sequences of cytochrome b (1,137 bases) and 12S
ribosomal RNA (961 bases) genes in mitochondrial DNA were successfully
determined from the woolly mammoth (Mammuthus primigenius), African
elephant (Loxodonta africana), and Asian elephant (Elephas maximus). From
these sequence data, phylogenetic relationships among three genera were
examined. Molecular phylogenetic trees reconstructed by the
neighbor-joining and the maximum parsimony methods provided an identical
topology both for cytochrome b and 12S rRNA genes. These results support
the "Mammuthus-Loxodonta" clade, which is contrary to some previous
morphological reports that Mammuthus is more closely related to Elephas
than to Loxodonta.
Nyakaana, S.,
Arctander, P., 1998. Isolation and characterization of microsatellite loci
in the African elephant,Loxodonta africana. Mol Ecol 7, 1436-1437.
Madsen, O.,
Deen, P.M., Pesole, G., Saccone, C., De Jong, W.W., 1997. Molecular
evolution of mammalian aquaporin-2: further evidence that elephant shrew
and aardvark join the paenungulate clade. Mol Biol Evol 14,
363-371.
Ozawa, T.,
Hayashi, S., Mikhelson, V.M., 1997. Phylogenetic position of mammoth and
Steller's sea cow within Tethytheria demonstrated by mitochondrial DNA
sequences. J Mol Evol 44, 406-413.
Abstract: Here we report DNA sequences from mitochondrial cytochrome b
gene segments (1,005 base pairs per species) for the extinct woolly
mammoth (Mammuthus primigenius) and Steller's sea cow (Hydrodamalis gigas)
and the extant Asian elephant (Elephas maximus), the Western Indian
manatee (Trichechus manatus), and the hyrax (Procavia capensis). These
molecular data have allowed us to construct the phylogeny for the
Tethytheria. Our molecular data resolve the trichotomy between the two
species of living elephants and the mammoth and confirm that the mammoth
was more closely related to the Asian elephant than to the African
elephant. Our data also suggest that the sea cow-dugong divergence was
likely as ancient as the dugong-manatee split, and it appears to have been
much earlier (22 million years ago) than had been previously estimated
(4-8 million years ago) by immunological comparison.
Yang, H.,
Golenberg, E.M., Shoshani, J., 1997. Proboscidean DNA from museum and
fossil specimens: an assessment of ancient DNA extraction and
amplification techniques. Biochem Genet 35, 165-179.
Lavergne, A.,
Douzery, E., Stichler, T., Catzeflis, F.M., Springer, M.S., 1996.
Interordinal mammalian relationships: evidence for paenungulate monophyly
is provided by complete mitochondrial 12S rRNA sequences. Mol Phylogenet
Evol 6, 245-158.
Abstract: The complete mitochondrial 12S rRNA sequences of 5 placental
mammals belonging to the 3 orders Sirenia, Proboscidea, and Hyracoidea are
reported together with phylogenetic analyses (distance and parsimony) of a
total of 51 mammalian orthologues. This 12S rRNA database now includes the
2 extant proboscideans (the African and Asiatic elephants Loxodonta
africana and Elephas maximus), 2 of the 3 extant sirenian genera (the sea
cow Dugong dugon and the West Indian manatee Trichechus manatus), and 2 of
the 3 extant hyracoid genera (the rock and tree hyraxes Procavia capensis
and Dendrohyrax dorsalis). The monophyly of the 3 orders Sirenia,
Proboscidea, and Hyracoidea is supported by all kinds of analysis. There
are 23 and 3 diagnostic substitutions shared by the 2 proboscideans and
the 2 hyracoids, respectively, but none by the 2 sirenians. The 2
proboscideans exhibit the fastest rates of 12S rRNA evolution among the 11
placental orders studied. Based on various taxonomic sampling methods
among eutherian orders and marsupial outgroups, the most strongly
supported clade in our comparisons clusters together the 3 orders Sirenia,
Proboscidea, and Hyracoidea in the superorder Paenungulata. Within
paenungulates, the grouping of sirenians and proboscideans within the
mirorder Tethytheria is observed. This branching pattern is supported by
all analyses by high bootstrap percentages (BPs) and decay indices. When
only one species is selected per order or suborder, the taxonomic sampling
leads to a relative variation in bootstrap Paernungulata (92-99%). When
each order or suborder is represented by two species, this relative
variation decreased to 10% for Tethytheria (78-87%) and 3% for
Paenungulata (96-99%). Two nearly exclusive synapomorphies for
paenungulates are identified in the form of one transitional compensatory
change, but none were detected for tethytherians. Such a robust and
reliable resolution of the paenungulate node implies a long history of the
common ancestors, allowing time for synapomorphies to accumulate. This
observation suggests a Late Cretaceous/Early Paleocene origin for the
Paenungulata.
Maliarchuk,
B.A., Derevenko, M.V., Lapinskii, A.G., Solovenchuk, L.L., 1996. The use
of the polymerase chain reaction in analyzing ancient DNAs (exemplified by
that of the Enmynveem mammoth). Izv Akad Nauk Ser Biol 6, 681-686.
Abstract: DNA was isolated from the Enmynveem mammoth muscles, and the
control region and cytochrome b gene of the mitochondrial genome were
analyzed by polymerase chain reaction (PCR). The mammoth DNA was amplified
by both the classical PCR (two primer system) and the single-primer PCR (spPCR)
resulting in DNA fragments up to 1600 bp long. Restriction analysis of the
mitochondrial cytochrome b gene was carried out. Cytochromes b genes in
three Elephantidae genera were compared.
Porter, C.A.,
Goodman, M., Stanhope, M.J., 1996. Evidence on mammalian phylogeny from
sequences of exon 28 of the von Willebrand factor gene. Mol Phylogenet
Evol 5, 89-101.
Abstract: Phylogenetic relationships among 27 extant mammalian species
(representing 15 placental orders) were studied using sequences of exon 28
of the gene encoding von Willebrand Factor (vWF), a glycoprotein which
functions in blood clotting. Analysis of sequences coding for vWF revealed
evidence for several subordinal and superordinal groupings, but the
earliest branching sequence of placental mammals was left largely
unresolved. Strong support was found for a monophyletic clade consisting
of elephants, sea cows, hyraxes, aardvarks, and elephant shrews. This
systematic placement of the elephant shrews agrees strongly with two other
molecular data sets (interphotoreceptor retinoid binding protein and
alpha-lens crystallins) and is consistent with analysis of fossil elephant
shrews recently discovered in north Africa. Evidence from vWF sequences
agrees with a number of previous molecular and morphological studies in
providing strong support for the monophyly of both bats and rodents. The
orders Primates, Proboscidea, Carnivora, Perissodactyla, and Artiodactyla
were represented by more than one species which joined in each case to
form a monophyletic order.
Rannala, B.,
Hartigan, J.A., 1996. Estimating gene flow in island populations. Genet
Res 67, 147-158.
Abstract: A new method is presented for estimating the rate of gene flow
into island populations using the distribution of alleles in samples from
a number of islands. The pseudo maximum likelihood estimator (PMLE) that
we derive may be applied to species with either discrete or continuous
generation times. For Wright's discrete-generation island model, the
method provides an estimate of theta = 2Nm where N is the (haploid)
population size on each island and m is the fraction of individuals
replaced by immigrants in each generation. For a continuous-generation
island model, the corresponding parameter theta is the ratio of the
immigration rate phi to the individual birth rate lambda. Monte Carlo
simulations are used to compare the statistical properties of the PMLE
with those of two alternative estimators of theta derived from Wright's
F-statistics. The PMLE is shown to have greatest efficiency (least mean
square error) in most cases for a wide range of sample sizes and parameter
values. The PMLE is applied to estimate theta using mtDNA haplotypes and
allozymes for subdivided populations of African elephants and Channel
Island foxes.
Stanhope, M.J.,
Smith, M.R., Waddell, V.G., Porter, C.A., Shivji, M.S., Goodman, M., 1996.
Mammalian evolution and the interphotoreceptor retinoid binding protein (IRBP)gene:
convincing evidence for several superordinal clades. J Mol Evol 43,
83-92.
Abstract: Phylogenetic relationships of 25 mammalian species representing
17 of the 18 eutherian orders were examined using DNA sequences from a
1.2-kb region of the 5' end of exon 1 of the single-copy nuclear gene
known as interphotoreceptor retinoid binding protein (IRBP). A wide
variety of methods of analysis of the DNA sequence, and of the translated
products, all supported a five-order clade consisting of elephant shrew (Macroscelidea)/aardvark
(Tubulidentata)/and the paenungulates (hyracoids, sirenians, and
elephants), with bootstrap support in all cases of 100%. The Paenungulata
was also strongly supported by these IRBP data. In the majority of
analyses this monophyletic five-order grouping was thefirst branch off the
tree after the Edentata. These results are highly congruent with two other
recent sources of molecular data. Another superordinal grouping, with
similar 100% bootstrap support in all of the same wide-ranging types of
analyses, was Artiodactyla/Cetacea. Other superordinal affinities,
suggested by the analyses, but with less convincing support, included a
Perissodactyla/Artiodactyla/Cetacea clade, an Insectivora/Chiroptera clade,
and Glires (an association of rodents and lagomorphs).
Yang, H.,
Golenberg, E.M., Shoshani, J., 1996. Phylogenetic resolution within the
Elephantidae using fossil DNA sequence from the American mastodon (Mammut
americanum) as an outgroup. Proc Natl Acad Sci U S A 93, 1190-1194.
Abstract: DNA was extracted from the extinct American mastodon, the
extinct woolly mammoth, and the modern Asian and African elephants to test
the traditional morphologically based phylogeny within Elephantidae.
Phylogenetic analyses of the aligned sequences of the mitochondrial gene
cytochrome b support a monophyletic Asian elephant-woolly mammoth clade
when the American mastodon is used as an outgroup. Previous molecular
studies were unable to resolve the relationships of the woolly mammoth,
Asian elephant, and African elephant because the sequences appear to have
evolved at heterogeneous rates and inappropriate outgroups were used for
analysis. The results demonstrate the usefulness of fossil molecular data
from appropriate sister taxa for resolving phylogenies of highly derived
or early radiating lineages. Erratum in: Proc Natl Acad Sci U S A 1996 Apr
30;93(9):4519
Bisig, D.A., Di
Iorio, E.E., Diederichs, K., 1995. Crystal structure of Asian elephant (Elephas
maximus) cyanometmyoglobin at 178-A resolution. Phe29(B10) accounts
for its unusual ligand binding properties. Journal of Biological Chemistry
270, 20752-20754.
Abstract: The crystal structure of Asian elephant cyano-metmyoglobin which
has a glutamine instead of the usual distal site histidine has been
determined to high resolution. In addition to this replacement, the
substitution of a conserved leucine residue in position 29(B10) at the
distal side by a phenylalanine was unambiguously identified based on the
available electron density. The suspicion, that there were errors in the
original sequence which has caused some confusion, is thus confirmed.
Comparison with other myoglobin structures in various ligated forms
reveals an essentially unchanged tertiary structure in elephant myoglobin
despite the two amino acid substitutions in the heme pocket. Our current
structural model shows that the N epsilon 2 atom of Gln64(E7) has moved
with respect to the corresponding nitrogen position of His64(E7) in the CO
complex of sperm whale myoglobin. The newly assigned residue Phe29(B10)
penetrates into the distal side of the heme pocket approaching the ligand
within van der Waals distance and causing a much more crowded heme pocket
compared to other myoglobins. Kinetic properties of Asian elephant
myoglobin, wild type, and recombinant sperm whale myoglobins are discussed
in relation to the structural consequences of the two amino acid
substitutions H64Q and L29F.
Fernando, P.,
1995. Implications of Socio-Ecology and Genetics on the Conservation and
Management of the Sri Lankan Elephant. In: Daniel, J.C. (Ed.), A Week with
Elephants; Proceedings of the International Seminar on Asian Elephants.
Bombay Natural History Society; Oxford University Press, Bombay, India,
pp. 225-235.
Hartl, G.B.,
Kurt, F., Hemmer, W., Nadlinger, K., 1995. Electrophoretic and chromosomal
variation in captive Asian elephants(Elephas maximus). Zoo Biology 14,
87-95.
Hauf, J., Baur,
A., Chalwatzis, N., Zimmermann, F.K., Joger, U., Lazarev, P.A., 1995.
Selective amplification of a mammoth mitochondrial cytochrome b fragment
using an elephant-specific primer. Curr Genet 27, 486-487.
Mezhzherin, S.V.,
Morozov-Leonov, S.I., 1995. The genetic differentiation of mammalian taxa:
their assessment by biochemical genetic markers. Zh Obshch Biol 56,
71-96.
Abstract: A review of data on genetic differentiation of mammalian taxa
has been made on the basis of estimating the percent of fixed gene
differences (PFD). The results substantiate the existence of evident
differences in the scale of genetic divergence between taxa in different
mammalian orders. Among smaller mammals (marsupials, insectivores,
chiropterans, myomorph and sciuromorph rodents, african mole rats, and
elephant shrews) interspecific differences within a genus involve the
average of 25-40% of investigated loci. At the genetic level the value is
50-60%, whereas at the familial level the differences are beyond the
resolution capacity of the method (PFD = 60-80%). Orders of larger mammals
can be divided into two subgroups. One of them that includes carnivores,
artiodactylans, and hystricomorph rodents is characterized by PFD values
of 10-14%, 30-50%, and 69-70% at respective levels. The other subgroup
composed of proboscideans, primates, pinnipeds, and toothed whales, has a
low level of
genetic divergence expressed by PFD values of 0-3%, 7-36%, and 50-60% at
species, generic and familial levels, respectively. Insufficiency of data
on baleen whales and Perissodactyla does not allow to cluster them
ultimately with any of these groups. There are three possible, but not
necessarily alternative, causes for the observed differences in genetic
divergence: 1) over-ranking of genera in larger mammals; 2) different
paleontological age of orders; 3) unequal rates of molecular evolution.
Queralt, R.,
Adroer, R., Oliva, R., Winkfein, R.J., Retief, J.D., Dixon, G.H., 1995.
Evolution of protamine P1 genes in mammals. Journal of Molecular Evolution
40, 601-607.
Abstract: A polymerase chain reaction-based approach was used to amplify
and sequence the protamine genes of the rat, guineapig (order Rodentia),
cat, bear (Carnivora), elephant (Proboscidea), horse (Perissodactyla),
camel, elk, deer, moose and gazelle (Artiodactyla). The predicted amino
acid sequences for these genes, together with previously reported amino
acid sequences of protamine genes of humans, mice, pigs, cattle, fowls,
quails and opossums, resulted in a data set of 25 P1 genes and 30 P1 amino
acid sequences. A bootstrapped DNA parsimony tree of the set of protamine
sequences was constructed. The results showed that protamines were amongst
the most rapidly diverging proteins studied. In spite of the large
differences, there were conserved motifs that were also common to birds.
The C-terminus appeared to be the most variable region. The molecular
evolution of P1 genes was in agreement with the expected species
evolution.
Siegismund,
H.R., Arctander, P., 1995. Structure of African elephant populations. J
Hered 86, 467-469.
Abstract: The structure of elephant populations from east and south Africa
has been analyzed by Georgiadis et al. (1994) on the basis of restriction
site variation of mitochondrial DNA. They used F statistics based on
identity by descent in tests for subdivision and reached the conclusion
that there was a significant differentiation at the continental level, but
that "populations were not significantly subdivided at the regional
levels." The data were reanalyzed by Monte-Carlo permutation tests where
population subdivision was tested by using F statistics based on
partitioning the total haplotype diversity among populations. This
resulted in identical conclusions at the continental level, but revealed
in addition a significant subdivision at the regional level indicating
haplotype frequency differences among the population.
Sukumar, R.,
1995. Minimum Viable Populations for Asian Elephant Conservation. In:
Daniel, J.C. (Ed.), A Week with Elephants; Proceedings of the
International Seminar on Asian Elephants. Bombay Natural History Society;
Oxford University Press, Bombay, India, pp. 279-288.
Sunderraj,
S.F.W., Mishra, B.K., Johnsingh, A.J.T., 1995. Elephant Use of Rajaji -
Corbett Forest Corridor, North West India. In: Daniel, J.C. (Ed.), A Week
with Elephants; Proceedings of the International Seminar on Asian
Elephants. Bombay Natural History Society; Oxford University Press,
Bombay, India, pp. 261-269.
Ye Htut, U.,
1995. Management of Wild Elephants in Myanmar. In: Daniel, J.C. (Ed.), A
Week with Elephants; Proceedings of the International Seminar on Asian
Elephants. Bombay Natural History Society; Oxford University Press,
Bombay, India, pp. 236-241.
Zhao, X., Vyas,
K., Nguyen, B.D., Rajarathnam, K., La Mar, G.N., Li, T., Phillips, G.N.,
Jr., Eich, R.F., Olson, J.S., Ling, J., 1995. A double mutant of sperm
whale myoglobin mimics the structure and function of elephant myoglobin. J
Biol Chem 270, 20763-20764.
Abstract: The functional, spectral, and structural properties of elephant
myoglobin and the L29F/H64Q mutant of sperm whale myoglobin have been
compared in detail by conventional kinetic techniques, infrared and
resonance Raman spectroscopy, 1H NMR, and x-ray crystallography. There is
a striking correspondence between the properties of the naturally
occurring elephant protein and those of the sperm whale double mutant,
both of which are quite distinct from those of native sperm whale
myoglobin and the single H64Q mutant. These results and the recent crystal
structure determination by Bisig et al. (Bisig, D. A., Di Iorio, E. E.,
Diederichs, K., Winterhalter, K. H., and Piontek, K. (1995) J. Biol. Chem.
270, 20754-20762) confirm that a Phe residue is present at position 29
(B10) in elephant myoglobin, and not a Leu residue as is reported in the
published amino acid sequence. The single Gln64(E7) substitution lowers
oxygen affinity approximately 5-fold and increases the rate of
autooxidation 3-fold. These unfavorable effects are reversed by the
Phe29(B10) replacement in both elephant myoglobin and the sperm whale
double mutant. The latter, genetically engineered protein was originally
constructed to be a blood substitute prototype with moderately low O2
affinity, large rate constants, and increased resistance to autooxidation.
Thus, the same distal pocket combination that we designed rationally on
the basis of proposed mechanisms for ligand binding and autooxidation is
also found in nature.
Bischof, L.L.,
Duffield, D.A., 1994. Relatedness estimation of captive Asian elephants
(Elephas maximas) by DNA fingerprinting. Zoo Biology 13, 77-82.
Georgiadis, N.,
Bischof, L., Templeton, A., Patton, J., Karesh, W., Western, D., 1994.
Structure and history of African elephant populations: I. Eastern and
southern Africa. J Hered 85, 100-104.
Abstract: Patterns of restriction site variation within mitochondrial DNA
(mtDNA) of 270 individuals were used to examine the current structure of
savanna elephant populations and to infer historical patterns of gene flow
across eastern and southern Africa. Elephants have a complex population
structure characterized by marked subdivision at the continental level (Fst
= 0.39; 95% confidence interval 0.19-0.58), and isolation by distance at
the regional level. However, phylogeographic analysis revealed evidence of
protracted gene flow across the continent. First, one relatively derived
haplotype was found at all sampling locations. Second, haplotypes
representing exceptionally divergent (up to 8.3%) mitochondrial clades
were found to coexist at distant (> 2,000 km) sampling locations. In the
few other species characterized by sympatric individuals bearing such
divergent haplotypes, all such individuals were found to coexist within
limited geographical regions. Accordingly, pronounced mitochondrial
divergence within populations is often attributed to ancestral isolation
in allopatry, followed by secondary contact. The patterns within elephants
do not accord with ancestral isolation in allopatry. Given the exceptional
mobility of elephants, a geographical barrier is unlikely to have
obstructed gene flow between regions for long enough to produce the
observed mitochondrial divergence. Rather, the patterns are consistent
with the more parsimonious hypothesis, based on neutral coalescent theory,
that gene flow has maintained a sufficiently large effective population
size (> 50,000 females) for representatives of clades that diverged at
least 4 million years ago to have persisted by chance within a population
that was subdivided, but not strictly isolated in allopatry.
Hagelberg, E.,
Thomas, M.G., Cook, C.E.Jr., Sher, A.V., Baryshnikov, G.F., Lister, A.M.,
1994. DNA from ancient mammoth bones. Nature 370, 333-334.
Hoss, M., Paabo,
S., Vereshchagin, N.K., 1994. Mammoth DNA sequences. Nature 370,
333.
Coetzee, E.M.,
Van-der-Bank, F.H., Critser, J.K., 1993. Allozyme variation in a wild
African elephant (Loxodonta africana) population from the Kruger National
Park, South Africa. Comparative Biochemistry and Physiology
B-Comparative-Biochemistry 106, 109-114.
Abstract: 1. Blood, liver, heart, testis, skin, eye, muscle and kidney
samples were obtained from elephants (Loxodonta africana) in the Kruger
National Park during a culling programme in April 1992. 2. Gene products
of 25 protein coding loci in L. africana were examined by horizontal
starch-gel electrophoresis. 3. Eighteen protein coding loci (72%)
displayed monomorphic gel banding patterns whereas only seven (28%)
displayed polymorphic gel banding patterns. 4. Average heterozygosity
values for adults, youngsters and the total population are respectively
0.058, 0.024 and 0.047. 5. Relative gene diversities within and between
populations are 84% and 16% respectively. 6. Two population simulation
programmes were utilized to predict the duration of the current
variability present in this species, based on current genetic variation
and gene transfer from one generation to the next.
Ermel, R.W.,
Kenny, T.P., Chen, P.P., Robbins, D.L., 1993. Molecular analysis of
rheumatoid factors derived from rheumatoid synovium suggests an
antigen-driven response in inflamed joints. Arthritis and Rheumatism 36,
380-388.
Abstract: Objective. Understanding the molecular genetic basis for
rheumatoid factor (RF) production is necessary to a better understanding
of the etiology and pathogenesis of rheumatoid arthritis (RA). We sought
to define the genetic basis for RF in RA. Methods. The heavy and light
chain variable region genes encoding 4 human monoclonal RF were cloned and
sequenced using the polymerase chain reaction and the dideoxynucleotide
chain-termination method. Results. The heavy and light chains of the C6
RF and the light chain of the G9 RF were encoded by 3 new RF-related Ig
V-region genes. The heavy and light chains of D5 and G4 RF's were
identical: most of their mutations caused amino acid substitutions.
Conclusions. The RF-related Ig V-region gene repertoire is large and
still expanding. The data from D5 and G4 strongly suggest that these 2
RF's arise in an antigen-driven response in rheumatoid synovium. The
presumed germline V genes for C6 may represent disease-specific RF-related
V genes.
Ma, D.P.,
Zharkikh, A., Graur, D., VandeBerg, J.L., Li, W.H., 1993. Structure and
evolution of opossum, guinea pig, and porcupine cytochrome b genes. J Mol
Evol 36, 327-334.
Abstract: We have sequenced the mitochondrial cytochrome b gene from the
guinea pig, the African porcupine, and a South American opossum. A
phylogenetic analysis, which includes 22 eutherian and four other
vertebrate cytochrome b sequences, indicates that the guinea pig and the
porcupine constitute a natural clade (Hystricomorpha) that is not a sister
group to the clade of mice and rats (Myomorpha). Therefore, the hypothesis
that the Rodentia is paraphyletic receives additional support. The
artiodactyls, the perissodactyls, and the cetaceans form a group that is
separated from the primates and the rodents. The 26 sequences are used to
study the structure/function relationships in cytochrome b, whose function
is electron transport. Most of the amino acid residues involved in the two
reaction centers are well conserved in evolution. The four histidines that
are believed to ligate the two hemes are invariant among the 26 sequences,
but their nearby residues are not well conserved in
evolution. The eight transmembrane domains represent some of the most
divergent regions in the cytochrome b sequence. The rate of nonsynonymous
substitution is considerably faster in the human and elephant lineages
than in other eutherian lineages; the faster rate might be due to
coevolution between cytochrome b and cytochrome c.
Sakthikumar,
A., Mukundan, G., Raghunandanan, K.V., 1992. Chromosome profile of Indian
elephants. In: Silas, E.G., Nair, M.K., Nirmalan, G. (Eds.), The Asian
Elephant: Ecology, Biology, Diseases, Conservation and Management
(Proceedings of the National Symposium on the Asian Elephant held at the
Kerala Agricultural University, Trichur, India, January 1989). Kerala
Agricultural University, Trichur, India, pp. 41-42.
Irwin, D.M.,
Kocher, T.D., Wilson, A.C., 1991. Evolution of the cytochrome b gene of
mammals. J Mol Evol 32, 128-144.
Abstract: With the polymerase chain reaction (PCR) and versatile primers
that amplify the whole cytochrome b gene (approximately 1140 bp), we
obtained 17 complete gene sequences representing three orders of hoofed
mammals (ungulates) and dolphins (cetaceans). The fossil record of some
ungulate lineages allowed estimation of the evolutionary rates for various
components of the cytochrome b DNA and amino acid sequences. The relative
rates of substitution at first, second, and third positions within codons
are in the ratio 10 to 1 to at least 33. For deep divergences (greater
than 5 million years) it appears that both replacements and silent
transversions in this mitochondrial gene can be used for phylogenetic
inference. Phylogenetic findings include the association of (1) cetaceans,
artiodactyls, and perissodactyls to the exclusion of elephants and humans,
(2) pronghorn and fallow deer to the exclusion of bovids (i.e., cow,
sheep, and goat), (3) sheep and goat to the exclusion of other pecorans
(i.e., cow, giraffe, deer, and pronghorn), and (4) advanced ruminants to
the exclusion of the chevrotain and other artiodactyls. Comparisons of
these cytochrome b sequences support current structure-function models for
this membrane-spanning protein. That part of the outer surface which
includes the Qo redox center is more constrained than the remainder of the
molecule, namely, the transmembrane segments and the surface that
protrudes into the mitochondrial matrix. Many of the amino acid
replacements within the transmembrane segments are exchanges between
hydrophobic residues (especially leucine, isoleucine, and valine).
Replacement changes at first and second positions of codons approximate a
negative binomial distribution, similar to other protein-coding sequences.
At four-fold degenerate positions of codons, the nucleotide substitutions
approximate a Poisson distribution, implying that the underlying
mutational spectrum is random with respect to position.
Sakthikumar,
A., Mukundan, G., Raghunandanan, K., 1990. Chromosome profile of Indian
elephants (Elephas maximus indicus). Indian Journal of Animal Sciences 60,
175-182.
Abstract: 15 elephants (7 males with tusks, 7 females and 1 male without
tusks) were karyotyped. The diploid chromosome number was 56. There were
12 submetacentric and 42 acrocentric autosomes, and 2 sex chromosomes. The
X-chromosome was submetacentric, and was the 4th largest chromosome; the
Y-chromosome was the smallest, and was acrocentric. The arm ratio of the
submetacentric chromosomes ranged from 1.38 to 4.23, and the centromeric
index ranged from 0.42 to 0.19. The karyotype of the tuskless male was
similar to that of the males with tusks.
Hegel, G.V.,
Hanichen, T., Mahnel, H., Wiesner, H., 1989. Warts (papilloma/sarcoid) in
elephant. Erkrankungen der Zootiere 31, 201-205.
Abstract: Warts ( Papilloma, Sarcoid) in Elephants ( Hegel,G.)1989;
translated from German by Gerda Martin. Papilloma virus - from the group
Papova virus - is considered an etiological agents of wart- like skin
changes in cattle, sheep, mountain goat, and rabbit. (ROSENBERGER,1970;
ROLLE and MAYR, 1984). Equine sarcoid (PALMER. 1985) found in horses is
most likely caused by bovine papilloma virus. The alternate name is based
on clinical and morphological differences in the actual papilloma. In the
initial stage, the sarcoid is similar to that of the papilloma; however in
later stages, tumorous decay on the surface of the epidermis, and
proliferation of the mesenchymal part of the tumor in the subcutis
dominate (DIET and WIESNER, 1982). Wart- like changes in the skin of
elephants as described by PILASKI et al (1987, 1988), proved to be caused
by Herpes virus. Such skin changes in elephants are not rare and require
treatment since size and volume of the excrescences may cause functional
disturbances in the patient. Even if the animal's general well being
is not impaired, the importance of esthetics and hygiene should not be
disregarded in a place where there are spectators and visitors (zoo,
circus). The following paper reports findings of wart- like skin changes
in elephants. Observations and Therapy In the elephants kept in the
Hellabrunn Zoo, no case of papilloma or similar skin tumors had occurred
since 1972. First case: In 5-28 - 1987, a ca. 18 month old female L.a.
named " Sabi" arrived In Hellabrunn. This animal had a wart- like
thickening of 1 cm at the dorsal end of the trunk. After 8 weeks, more of
those such skin changes appeared on trunk and lower lip without
impairment in general well being. Treatment consisted of one daily,
subcutaneous injection of 1 amp. Chelidonium D7 (DHU Chelidonium majus
L.), and application of fresh ??Schoellkraut juice dabbed onto the warts
but was unsuccessful. After a change of treatment was made: 10 drops of
Thuja D4 (DHU Thuja occidentalis L) and 20 drops Acidum nitricum D12 (DHU
Acidum nitricum), orally, once a day, at separate times of the day, there
remained, after 2 weeks, a wart on the lower lip the size of a cherry pit,
and the before mentioned wart on the dorsal end of the trunk had now
grown to the size of a cherry. Even the strength of Thuja LM 6 (DHU Thuja
occidentalis L.) 20 drops, oral, the growth of the wart on the dorsal end
of the trunk, now with a diameter of 5 cm, could not be stopped:
Exstirpation had to be performed. Frequent sucking had promoted strong
ulceration. A secondary infection had set in, the surface showed
granular tissue exuding blood and pus.
On 10 - 6 - 1987 the growth was exstirpated and tissue was sent for
virolog. and histolog. examination. In addition, tissue was removed from a
fresh small wart for vaccine. During the operation the animal was
immobilized (anesthetic: 0.3 ml Immobilon* (large animal Immobilon Rc* -
Vet. Ltd.), 10mg Xylacin, 150 IE Hyaluronidase i. m.). There were no
complications during recovery. Two weeks post op., the first vaccination
was given, followed by a second vacc. four weeks there after, of 5.0 ml,
subcut.., of an auto vaccine developed by the Institute for Medical
Microbiology, Dept. of Infectious and Epidemic Medicine. In February 1988,
there occurred another bout with wart- like growth on the ventral part of
the trunk, lower jaw, shoulders and feet, some with a diameter of 15 mm.
From the sedated young animal tissue was taken from several newly grown
warts for the manufacture of auto vaccine (sedation: "Hellabrunner
Mischung" / 150 IE Hyaluronidase). After 10 days, the first vaccination
was given, and by the time of the second vacc." Sabi" was free of
externally visible skin changes.
On 6. 6. 1988, "Sabi" fell ill again. Over night she was covered with 48
warts, with diameters from 2mm - 15 mm on trunk and head, and 10 more on
the chest.The attempt to "ice" the warts with liquid nitrogen was not
successful. Instead, coagulation of ca. 20 of the larger warts was used.
The monopolar coagulation electrode of the Erbotom F 2 (Erbe
Elektromedizin) coagulates reaching deeply into the healthy zone of the
surrounding tissue. As before, tissue for the manufacture of the auto
vaccine was taken, as well as 0.5 ml of blood from the ear vein for the
manufacture of a "own- blood" nosode. (Large animal, premedication: 20 mg
Xylazin i.m., 20 minutes later : 0.5 ml Immobilon R (large animal
Immobilon R c - Vet Ltd.) and 150 IE Hyaluronidase i.m. The following day,
"Sabi" was given the "own- blood" nosode at a strength of C5 (20 drops
daily).In addition, she was vacc. once again. Since "Sabi" was free of
warts at the time of the second vaccination - given 4 weeks after the
first - the "own- blood" treatment was discontinued. Shortly there after,
however, several new warts cropped up (diameter ca. 1 cm), so that the
"own- blood" treatments were continued. Since that time "Sabi" has had no
recurrences.Second case : The Indian elephant cow (E. maximus) , named
"Dirndl" , age ca. 22 years, had been kept in the box next to "Sabi" since
"Sabi's" arrival. They kept trunk contact. On 5-2-1988, "Dirndl" showed on
the distal trunk a substantially increased raised area ca. 2 x 2 cm oozing
blood. It seemed to be an injury from a metal rope used in off limiting.
The wound was disinfected and treated twice a day with chloromycetin spray
with Gentian violetR (Parke Davis). After one week the growth had
increased substantially and on the surface, it had a cauliflower-like
ulcerated appearance.Upon light touch or movement of the dorsal trunk,
blood appeard spontaneously. Four days later, the growth was exstirpated,
while the animal was standing. (Sedation: 2.2 ml Hellabrunn mixture / 150
Hyaluronidase i. m.) . The attempt to close the skin of the trunk over the
wound failed because the tension in that area was too great. The surface
of the wound was cauterized and treated with ChloromycetinSpray with
Gentian violet R (Parke Davis). Tissue for pathological and histological
examination was sent out. One week after the operation, the area of the
wound was highly swollem and the wound was infected. Treatment: Several
times a day, an ablution with a 0.1 % Rivanol solutionnR (Asid - 2
Aethoxy-6.9-diamin acridinlactat) and application of Sulfonamid-Codliver
oil salve (WDT = Sulfadimidin- Sodium- cod liver oil). In addition,
analogous to "Sabi" , once daily 20 drops of "own-blood" nosode, potency
C 5 given orally. Three weeks post. op., there could be clearly
distinguished a limited relapse, an area of 6 x 9 cm rising ca. 2 cm
above the healthy skin of the trunk. The surface looked like the first
growth. It was extirpated under general anesthetic (Premed.:80 mg
Xylazin i. m., 20 min. later: 1.8 ml ImmobilionR and 150 IE Hyaluronidase).
In addition, the whole wound was coagulated by monopolar coagulation
electrode as above. Daily for 4 weeks, the wound was brushed with a 1:5
wood tar -alcohol - solution.There were no complications during recovery.
After 5 weeks , all that could be seen was a ca. 1.5 cm long small scar on
the skin of the trunk.
Histomorphological Findings: Fixation with formalin, embedding in
paraffin; stain: Hemalaun-Eosin, connective tissue stain in the manner of
Masson. The histomorphological findings based on the tissue samples of "Sabi"
and "Dirndl" are the same, and agree with the findings of 3 other skin
tumor tissue taken from elephants of different origin (tab. 1). The
tumors consist mainly of fibroplastic cells with more or less abundant
collagen fibers and blood vessels. The boundaries from the adjacent corium
and lower skin is largely indistinct. In all larger neoplasties , the
covering epidermis has been preserved at margins only due to superficial
ulceration. Here the P. acuta aseptica diffusa borders are irregular and
strongly profiled, the epithelium is acanthoid and hyperkeratotic. The
nuclei of tumor cells are considerably anisomorphic, some have gigantic
nuclei. Mitosis is frequent. Due to the ulcerated epidermis , there is
deep infiltration with infectious cells. Virological findings: From the
extirpated tissue taken from the African Elephant "Sabi" ca. 3 g was
homogenated, in addition, the cells were "opened" by defrosting and
ultrasound, and the "cleared" tissue suspension was analyzed for free
virus particles after concentration and negative-contrasting with
electron microscopy . At the same time, small tissue samples of 2 mm
from deeper epidermis layers were fixed as usual for the
ultrahistological exam , embedded in epoxy resin, and ultra thin slices
were scanned by the electron microscope. No papilloma virus was found in
the concentrated, cell free tissue extract or the ultrathin slices of
tissue samples .No virus particle of any kind was found.
Discussion
To show papilloma by culturing cannot be done since no species of this
genus can be propagated in cell cultures with the exception of its
original host. The failed attempt to prove their presence with the
electronmicroscope does not exclude a papilloma virus etiology in tumors.
When virus particles are viewed in higher concentrations, the electron
microscopic proof is successful. Using ultrahistologyical methods the
particles in cell nuclei can only be found when the few cells of specific
skin cells are in the virus propagation stage. In the case of virally
induced papilloma however, a true virus propagation is not necessary. In
the last few years, it was found that equine sarcoid can be caused by
bovine papilloma virus. But it was only the genome of the virus which
could be isolated by means of gene technology (ALTMANN, 1980; HAUSEN,
1980); the virus itself could not. The oncogenetic potency of the virus
in heterologic hosts , without true virus production, has been
established. A broader spectrum of hosts for , at least , the papilloma
virus in cattle seems to be the case. And a bovine papilloma induced skin
fibromatose in (a) horse has been reported (LANCASTER, 1979). This virus
can also appear in wild 'cud chewers, perhaps even carnivores. It is in
part also related to the human papilloma virus. The possibility of
transfer to humans (LANCASTER 1982) as well as other mammals such as
elephants has not been proved but is probable. In comparing the
histological findings of the 5 skin growths with those of the viral
fibropapilloma in cattle and horse (called equine sarcoid here), the
relative immaturity of the tumorous tissue is evident. It compares to the
so- called sarcoid in horses. The sarcoid-like structure and the
indistinct separation from healthy tissue speaks for a virus etiology
and morphologically a relapse can be expected. This occurred in both of
the clinically described cases.
A differential diagnosis excludes a Herpes virus infection, as described
by PILASKI et al. (1987, 1988) in elephants on the basis of different
histological findings. Inclusions could not be found in any of the cases.
The warts on the elephants were clinically similar to the well known
sarcoids in horses (DIETZ and WIESNER, 1982). The two sick animals were in
"trunk contact" occupying adjacent boxes. Almost one year after the
arrival of "Sabi" who had warts, "Dirndl" fell sick. That points to the
infectious nature of warts. The relapse after the first operation on
"Dirndl" suggests that the extirpation of the growths was not complete.
This may be related to the fact that the animal was standing and only
sedated. In contrast , the extirpation of the "relapse" was carried out on
a fully immobilized animal and with the use of the Erbotom F 2 for
coagulation including the adjacent tissue. We know of various 'wart
therapies' in human medicine with differing success. The various
treatments employed in the one and one half years of "Sabi's" illness can
be labled neither successful, nor unsuccessful. The use of auto vaccine
which is analogous to a "stable specific " vaccine in the treatment of
papilloma in cattle, could perhaps have triggered the recurrence of warts
at the conclusion of the vaccination treatments. That would favor the
etiology of a virus 'picture.' The influence of the 'burn' or extirpation
of a single or more growths which returned, in the surrounding growths
cannot be determined. It remains inconclusive if the use of the "own-
blood" nosode C 5 aided the successful therapy , since the necessity to
fight a recurrence had not yet occurred.
Merkt, H.,
Bader, H., Rath, D., Dittrich, L., 1987. An attempt to deep-freeze
elephant semen. Deutsche Tierarztliche Wochenschrift 94, 488-489.
Howard, J.G.,
Bush, M., de Vos, V., Schiewe, M.C., Pursel, V.G., Wildt, D.E., 1986.
Influence of cryoprotective diluent on post-thaw viability and acrosomal
integrity of spermatozoa of the African elephant (Loxodonta africana).
Journal of Reproduction and Fertility 78, 295-306.
Abstract: Electroejaculates from free-ranging African elephants were
frozen to test various seminal diluents, freezing methods and thawing
media on post-thaw sperm viability and structural integrity. In Study I,
each ejaculate was tested in each of 7 cryoprotective diluents. After
cooling to 5C and equilibration on ice (4C) for 120min, each aliquot was
pellet frozen on solid CO2, stored in liquid nitrogen and
thawed (37C) in saline or tissue culture solution. Amongst the diluents,
post-thaw sperm motility, motility duration in vitro (37C) and acrosomal
integrity were greatest when diluent BF5F was used. Thawing medium had no
effect on results. In Study II, the optimal diluent from Study I (BF5F)
was compared with the diluent SGI. Results were not affected by a 90- or a
150-min cooling-equilibrium interval in an electronic cooler (5C);
however, post-thaw sperm motility rating and duration of motility in vitro
were grater with the pellet than the straw container freezing method.
When the pelleting method was used, diluents BF5F and SGI provided
comparable cryoprotection. Duration of post-thaw motility was enhanced
2-fold and up to 12h my maintaining thawed semen at 21 rather than 37C.
All diluents provided some protection on acrosomal integrity, but the
overall proportion of intact acrosomes after thawing was markedly less in
Study II, apparently as a result of the slower initial cooling rate
(approx 1.5C/min) compared to that of Study I (approx 6.5C/min). This
study demonstrates the feasibility of cryopreserving semen from
free-ranging African elephants and indicates that spermatozoa most
effectively survive freezing when the BF5F or SGI diluent is used in
conjunction with the pelleting method.
Pilaski, J.,
Rosen, A., Darai, G., 1986. Comparative analysis of the genomes of
orthopoxviruses isolated from elephant, rhinoceros, and okapi by
restriction enzymes. Brief report. Archives of Virology 88,
135-142.
Abstract: Orthopoxviruses from different zoo-kept mammalian species
including Elephas maximus (8 isolates), Ceratotherium simum (1 isolate),
and Okapia johnstoni (2 isolates) were characterized by restriction enzyme
analysis of the viral genome. The four enzymes BamHI, MluI, NcoI, and SalI
were found to be optimal for strain differentiation.
Ryder, O.A.,
1986. Genetic investigations: tools for supportings breeding programme
goals. International Zoo Yearbook 24/25, 157-162.
Howard, J.G.,
Bush, M., Schiewe, M.C., de Vos, V., Wildt, D.E., 1985. Further
developments in comparative semen freezing in free-ranging African
elephants. Proceedings American Association of Zoo Veterinarians 31-32.
Johnson, P.H.,
Olson, C.B., Goodman, M., 1985. Isolation and characterization of
deoxyribonucleic acid from tissue of the woolly mammoth, Mammuthus
primigenius. Comp Biochem Physiol B 81, 1045-1051.
Abstract: DNA was isolated from tissue samples of several mammoth
specimens, radiocarbon dated between 10,000 and 53,000 years old. The DNA
was purified by chromatography on hydroxyapatite at 60 degrees C and was
characterized as a heterogeneous population of fragments ranging in size
from 3000 to 200 base pairs. Thermal denaturation analysis demonstrated
that approximately 25% of the DNA had a base composition similar to Asian
elephant DNA calculated as 36% G + C. Preliminary analysis by nucleic acid
hybridization indicated that only a small fraction of DNA isolated from
mammoth tissue (2-5%) was homologous to DNA of Asian elephant, a close
living relative of the mammoth. Our results provide the first definitive
isolation and characterization of DNA from ancient tissue and suggest a
purification strategy that will lead to preparations of DNA from mammoth
tissue significantly enriched in elephant-related DNA sequences.
1979. "Motty"
-- Birth of an African/Asian elephant at Chester Zoo. Elephant 1,
36-40.
De Jong, W.W.,
Nuy-Terwindt, E.C., Versteeg, M., 1977. Primary structures of alpha
crystallin A chains of elephant, whale, hyrax and rhinoceros. Biochim.
Biophys. Acta 491, 573-580.
Abstract: As part of a study of the evolutionary development of the eye
lens protein alpha-crystallin the 173 residue A chain of this protein has
been studied in elephant, whale, hyrax and rhinoceros. The primary
sturctures were inferred mainly from amino acid compositions of peptides
obtained by enzymatic digestions and CNBr cleavage. The positions of
substitutions, as compared to known bovine A chain, were confirmed by
Edman degradation. In accordance with the previously observed slow rate
of evolution of the A chain only a small number of substitutions were
found among these species. Elephant and hyrax share a number of unique
substitutions, strongly indicating a common ancestry of these two species
within the mammalian class.
Jones, R.C.,
Bailey, D.W., Skinner, J.D., 1975. Studies on the collection and storage
of semen from the African elephant, Loxodonta africana. Koedoe 18,
147-164.
Thurig, D.,
1970. Karyotype and sex chromatin of the African elephant. Acta Anatomica
Nipponica 75, 6-12.
Norberg, H.S.,
1969. The chromosomes of the Indian female elephant (Elephas indicus
Syn. E. maximus). Hereditas 63, 279-281.
Hooijer, D.A.,
1967. Indo-Australian insular elephants. Genetica 38, 143-162.
Hungerford,
D.A., Chandra, H.S., Snyder, R.L., Ulmer, F.A., 1966. Chromosomes of three
elephants, two Asian (Elephas maximus) and one African (Loxodonta
africana). Cytogenetics 5, 243-246.
Abstract: Cultured somatic cells of three elephants, male and female Asian
(Elephas maximus) and female African (Loxodonta africana),
had 56 chromosomes. Karyotypes of the Asian specimens were
morphologically identical, except for the sex chromosomes, and that of the
African specimen closely similar. Identification of the African X was made
by inference.
Rao, S.R.V.,
Prasad, M.R.N., 1963. The nuclear sex in the Indian elephant, Elephas
maximus L. Naturwissenechaften 50, 313.
Venkatasubba,
R.S.R., Prasad, M.R.N., 1963. The nuclear sex in the Indian elephant,
Elephas maximus L. Naturwissenechaften 50, 313.
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