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The large body size of the elephant and the dearth of pharmacokinetic
studies make determining appropriate medications and dosages for elephants
a challenging task. This is further complicated by the actual
administration of treatment once a drug and a dose have been decided.
As with any species, therapy begins with an accurate diagnosis. The
chosen medications must be appropriate for the condition being treated and
they must be administered at the proper dosage and interval if therapeutic
success is to be achieved.
Whenever possible, an accurate weight should be obtained. If a scale is
not available, weight can be estimated using the techniques recommended in
the chapter
Estimating Weights of Elephants.
Regardless of the medication technique selected, the safety of all staff
involved must be a primary consideration.
The gustatory sense seems to be well developed in elephants and they are
notorious for their refusal of oral medications. There are a number of
ways to administer drugs orally to elephants. The most simple is to mix
the medication with food. Medications are typically hidden in favorite or
flavorful foods and a great deal of experimentation may be necessary to
identify suitable food disguises, especially for bitter tasting drugs.
Chocolate and mint flavor can mask bitter tastes and in general, elephants
seem fond of sweets. Table 1 lists food items that have been used
successfully. The list is by no means complete.
If the medication is cooked or frozen with food, it is advisable to
determine that such alterations do not change the chemical properties or
the stability of the drug. Information on storage, stability, and
compatibility is included with most of the drug monographs in this
manual. Captive elephants may be more willing to accept medications from
a familiar handler than from the veterinarian (Olsen, 1999).
Although mixing medications with food is easy, it may be difficult to
determine the amount of drug consumed as there is almost always spillage
or separation. It is not practical to administer drugs in the drinking
water for the same reason and also because elephants spray their water.
For accuracy of dosing, whenever possible, oral medications should be
delivered directly.
The occasional elephant will simply open its mouth and permit medications
to be placed (or better, tossed) into the oral cavity but this is
uncommon. Even if successful at first try, this may not be repeatable or
reliable particularly with ill-tasting drugs.
Caution:
even the most tractable of elephants
may respond quickly to a sudden movement or distasteful food and a hand
could be crushed.
 Bite blocks (gags) can be used but the elephant must be trained to accept
the procedure. The center hole is designed to permit the hand to pass
through and safely deliver pills directly or in small boluses of food to
the back of the throat. Care must be taken that the force of the tongue does not
push the hand to the side between the molars. Liquid medications may be
administered by using a large animal dose syringe and tubing.
The following suggestions are offered to facilitate bite block training
(Johnson, 2003):
1. Start with a bite block and a 6-ounce dose syringe with a modified 18"
nozzle.
2. Train the elephant to the bite block with sugar water or something they
like first. The elephant should open the mouth to accept the block and
let it stay there until you take it out.
The nozzle should be placed over the tongue muscle and toward the center
of the mouth away from the teeth.
3. Administer the solution slowly.
4. Leave the block in for a short time after you give the liquid to make
sure it goes down.
5. Trunk the elephant up immediately afterward to keep them from sucking
the liquid out with their trunk. It is very easy for them to spit out.
6. Try walking the elephant around with the trunk up or have them go
through a series of behaviors. This will encourage swallowing.
7. Once used to the taste, the elephants may open their mouths willingly.
In this case, use of the bite block can be discontinued.
There are a few veterinary pharmacies in the U.S. that will compound
medications for elephants using a variety of flavor enhancers. These are
listed in Table 2.
Despite their large size and thick skin, elephants are quite sensitive to
injections. Repeated injections on a long-term basis are unlikely to be
tolerated. The training and personality of the elephant, the restraint
facilities available and the confidence and skill of the handler determine
the ease of administering medications by injection. The choice of
injectable medications is also limited. The calculated volume of drug may
be so large as to preclude its practical use.
If an elephant restraint device or squeeze is available, it can be
utilized when giving injections. In the absence of such a device, human
safety can be maximized by laying the elephant down. In this position the
elephant cannot react as quickly (Oisen, 1999). Alternatively, asking the
handler to have the elephant hold up one leg will also slow reaction time.
In field situations, mahouts are often skilled at rope restraint and
elephants may be tethered to trees to restrict movement. A figure-8 rope
applied to the hind legs can both restrict movement and prevent kicking.
Ropes are sometimes applied to the neck. This poses a danger of
strangulation if the elephant goes down. If neck ropes are used it is
essential that appropriate equipment is at the site to cut the ropes
quickly in case of an emergency.
 Pole syringes (jabsticks) can be used for remote injection. Models with
spring loading are generally more effective as medication is injected
rapidly (< 1 second). The addition of an extension poles on some models
can further increase the elephant-to-operator distance. A disadvantage is
that the syringe volume is generally 12 cc or less making repeated
injections necessary.
In dangerous animals where other options are not available, remote
projectors and darts may need to be employed. Injectable medications are given by the intramuscular, subcutaneous, or
intravenous route.
Intramuscular 
Elephants readily form abscesses so it is very important that
intramuscular injection sites be thoroughly cleaned prior to injection.
Commonly used injection sites include the lateral foreleg (triceps
muscles), the hindleg, hip, and the neck.
Note that the skin on the hip and
upper hind leg is thick ( ≥ 2.5 cm); skin on the foreleg is thinner.
Injections should be given into large muscle masses. Depress the plunger
of the syringe slowly to avoid pain and trauma to the underlying tissue.
Swelling may result from injections that are given too fast.
To insure injection into the muscle, needles of sufficient length must be
used. Needles 1.5 inches (3.75 cm) long are adequate for the foreleg
injections, but 2.0 – 3.0 inch (5.08 – 7.62 cm) may be needed to reach
muscle in the hindleg of adult elephants. Standard hypodermic needles are
generally not supplied in lengths greater than 1.5 inches (3.75 cm) so it
may be necessary to use spinal needles to achieve the appropriate
injection depth. Eighteen gauge needles are adequate for most injections
but a larger gauge (14 or 16) may facilitate injection of thick
medications.
Recommended maximum volumes per injection site should not exceed 25 ml
(Olsen,1999) and some clinicians recommend 10 – 20 ml (Schmidt, 1986). If
larger volumes are given, inflammation may result. Dimethyl sulfoxide (DMSO)
can be applied to reduce swelling at injections sites (Schmidt, 1986).
Although it may be safer to give an injection when the elephant is laying
down, in the author’s experience, achieving an intramuscular injection is
more likely on a weight-bearing leg as the muscle is taut and closer to
the skin surface.
The subcutaneous route is not recommended in elephants unless the drug is
specifically labeled to be given by this route and not intramuscularly.
Absorption from subcutaneous tissues in elephants has not been studied and
is questionable. Use of short needles may result in inadvertent
subcutaneous injection.
The auricular, cephalic, and saphenous veins can be used to administer
intravenous medications. The large auricular veins are the most
accessible and can be distinguished from nearby arteries by their thinner
and more pliable walls and the absence of a pulse. By contrast, the
arteries are thicker and rope-like on palpation and pulsations can usually
be detected. The external pinnae plays a major role in thermoregulation,
particularly in the African elephant. Consequently, auricular veins may
dilate in warm temperatures and constrict in cold. Placing elephants in
lateral recumbency encourages the veins to fill. The application of warm
compresses or dry heat (using a hair dryer) encourages vasodilation and
facilitates venipuncture in cold weather or when blood pressure is low.
CAUTION ! Some intravenous drugs can be
irritating when injected perivascularly. Care should be taken to insure
that the needle is securely in the vein, particularly when using the
auricular veins. Segmental gangrene of the ear has resulted from the
perivascular administration of phenylbutazone (Miller, 1977).
To minimize the potential for iatrogenic sloughing of the ear: 1) use leg
veins instead, 2) administer the drug under light sedation to prevent
struggling and ear flapping, 3) use an intravenous catheter, and 4) dilute
the drug with saline or sterile water (Schmidt, 1986).
  The cephalic vein on the proximal medial forelimb is prominent in some
elephants but can be difficult to visualize in others. It can be accessed
with the elephant standing but places the operator at risk from head and
trunk movements in free contact situations.
 The saphenous vein, on the lower medial aspect of the hindleg, can be
approached with the elephant standing, in a stretched position, or in
lateral recumbency. This vein is deeper than it appears and usually
requires a one-inch needle inserted to its depth at a 90 º angle.
Intravenous injections can be administered with a syringe and needle. With
larger volumes winged infusion sets (butterfly catheters) are helpful.
The tubing permits the operator to follow any movements of the elephant
without jeopardizing the position of the needle in the vein. Intravenous catheters can be are placed for repeated injections, but the
elephant must be under constant supervision to prevent their removal.
Allergic drug reactions are rare but possible and the clinician should be
prepared for this occurrence.
Regional Digital Intravenous Perfusion
Regional digital intravenous perfusion has been used to administer
antibiotics for treatment of phalangeal osteomyelitis in a 45-year old
female African elephant. The technique was modeled after methods used in
domestic horses and cattle and used a pneumatic tourniquet designed for
elephant foot surgery (Spelman, et.al. 2000).
Rectal administration is an effective alternative for the administration
of oral medications. The rectal mucosa seems to provide an absorptive
surface comparable to the upper gastrointestinal tract. Effective blood
levels have been demonstrated with rectally administered metronidazole (Gulland,
1987) and with anti-tuberculosis drugs (unpublished work).
PROTOCOL FOR RECTAL TREATMENT (Riddle, 2003):
EQUIPMENT:
· Long sleeve OB type disposable gloves
· Lubricant
· Large dose syringe (400ml)
· Flexible plastic flexible tubing (approximately 2 ½ feet long) such as that
used to worm horses
· Medication
· Hot water
METHOD:
To make the enema solution, dissolve the medication (tablets and / or
powdered drugs) in approximately 60 ml hot water, in a container with
a lid, for about an hour. Put on a long OB glove, lubricate the glove well,
and clean out the elephant (remove feces from rectum) completely.
Immediately before administration of the enema solution, add an
additional 40-60 ml hot water to the container with the medication,
close the top and shake well, then draw it into a dose syringe. The
solution should be warm, not too hot to be uncomfortable for the animal.
Attach the tube to the end of the dose syringe. Holding the end of the
tube in one hand, insert arm into the rectum. Pass the tubing as far
up the rectum as possible then withdraw arm, keeping the tube in place
in the rectum. Depress the plunger, injecting the liquid with the dissolved
medication into the rectal tract. While the tube is still in the rectum,
unscrew the syringe, fill with air, then reattach and inject the air to flush
any remaining medication from the tube. Remove the tubing from the r
ectum by pulling the syringe straight up to empty any residual medication
in the tube as it is withdrawn from the rectum.
The subject of wound treatment is an extensive topic beyond the scope of
this Formulary. Brief mention will be made of techniques commonly used in
elephants. The reader is urged to consult other references and
experienced colleagues for more detailed information. Topical treatment
agent monographs will be added to this Formulary at a later date.
A variety of products are available for the treatment of superficial
wounds. These include ointments, powders and sprays. Keeping the area
clean is often as or more important than the particular agent used and
this may need to be done frequently. Some ointments adhere better than
others. In the author’s experience zinc oxide ointment has good adhering
qualities and encourages granulation tissue, however, for leg wounds,
powder-based products (such as Wonder Dust®) are preferred.
Wound Irrigation (also called lavage, flushing)
Irrigation is a widely accepted technique to reduce the presence of
foreign materials and bacteria in deeper wounds and thus promote healing.
Controlled wound irrigation is less traumatic to tissue, less painful, and
more effective in removing foreign material and reducing the bacterial
load than swabbing. A variety of lavage solutions have been recommended
including sterile saline, dilute povidone iodine, dilute chlorhexidine,
and others. These agents will be reviewed in a later edition of The
Elephant Formulary.
Devices to administer wound irrigation include a raised fluid bag with
attached tubing permitting gravity flow, bulb syringes (a large basting
syringe used in cooking, for example), a 35 or 60 cc syringe with blunt
needle or tubing attached, and hand-held or back-pack style garden
sprayers.
It is important to use copious amounts of the lavage solution – at least
250 ml. Low pressure is ineffective in removing contaminants and bacteria
and high pressure can damage tissue and force bacteria deeper into the
wound. Moderate pressure (9-25 psi) is best (Mills, 1999).
Bandages:
Wounds on lower limbs can be bandaged but elephants rarely leave bandages
in place for long. In field situations, bandages can be improvised. A number of bandaging techniques, primarily for feet,
have been described. See the references listed below (Houser et.al. 2001,
Myszkowski,1990, Woodle et.al. 2001).
 Compresses
The application of heat can help to reduce pain and swelling or to draw
infection to the surface of a wound and encourage draining. Heat can
be applied in the form of warm compresses using towels.
In Thailand, herbal compresses are applied using a rag
mop
Soaking is generally applied to foot injuries and requires some training
of the elephant to accept the procedure. Once this is accomplished,
cooperation is generally good as the procedure is usually pleasurable.
Administering ophthalmic preparations to elephants is not easy. Most
elephants resent having the area around their eyes manipulated and it is
difficult if not impossible to force their eyelids open. Long eyelashes on
some elephants further complicate the task as does the frequency with
which most preparations must be administered to be effective. Ophthalmic
preparations are available as drops or ointments. The choice of which form
to use is best determined by the personality of the elephant and the skill
of the handler to apply the product.
Using a small spray bottle has been suggested as a more effective method
to administer eye drops (Clausen, 2001). Commercial liquid products can
be transferred into the spray bottle, however it may be more economical to
formulate sprays (by mixing gentamycin with sterile saline, for example,
in dilutions equivalent to the commercial product). The elephant handler
or mahout can carry the spray bottle and apply the medication
opportunistically throughout the day.
Table 1 Foods used to deliver oral medications to elephants
chocolate
donuts
molasses
mint flavor
bread
ice cream
coke
jello (medication molded in)
bread
bananas
fruit juice
pineapple (cut a window then plug)
small papayas
honey
popsicles
sweetened rice balls
Clausen, Bjarne (Danish Animal Welfare Society). 2001. Personal
communication.
Gulland,F.M. and Carwardine,P.C. 1987. Plasma metronidazole levels in an
Indian elephant (Elephas maximus) after rectal administration. Veterinary
Record 120:440
Houser,D., Simmons,L.G., and Armstrong,D.L., 2001. Treatment of an
abscessed footpad of an African elephant (Loxodonta africana) using
a sandal and topically applied chitosan. In: Csuti,B., Sargent,E.L., and
Bechert,U.S. (Editors), The Elephant's Foot. Iowa State University Press,
Ames, Iowa, USA pp. 107-113
Johnson, Kari and Johnson, Gary. 2003. Personal communication. Have Trunk
Will Travel, 27575 Hwy 74, Perris, CA 92570, www.havetrunkwilltravel.com
Mikota, S.K. and Hammatt, H. 2003. Personal communication.
www.elephantcare.org
Miller,R.M. 1977. Segmental gangrene and sloughing of elephants' ears
after intravenous injection of phenylbutazone. Veterinary Medicine Small
Animal Clinician 72:(4):633-637
Mills,N.J. 1999. The importance of wound lavage. International Veterinary
Wound Management Forum 1:(1):2-4
Myszkowski,J. 1990. Bandaging a toe abscess on an Asian elephant (Elephas
maximus). Proc Ann Elephant workshop 11.
Olsen,J.H., 1999. Antibiotic therapy in elephants. In: Fowler,M.E. and
Miller R.E. (Editors), Zoo and Wild Animal Medicine: Current Therapy 4.
W.B. Saunders, Philadelphia, PA,USA pp. 533-541
Riddle,H. 2003. Personal communication. Riddle’s Elephant and Wildlife
Sanctuary, www.elephantsanctuary.org.
Schmidt,M.J., 1986. Proboscidea (Elephants). In: Fowler,M.E. (Editor), Zoo
and wild animal medicine. W.B. Saunders, Philadelphia,PA, USA p.896.
Spelman,L., Yates,R., Anikis,P., and Galuppo,L. 2000. Regional Digital
Intravenous Perfusion in an African Elephant (Loxodonta africana).
2000 Proceedings AAZV and IAAAM Joint Conference. Pages: 388-389
Woodle,K., Kepes,T., and Doyle,C., 2001. Making a protective boot for an
Asian elephant. In: Csuti,B., Sargent,E.L., and Bechert,U.S. (Editors),
The Elephant's Foot. Iowa State University Press, Ames, Iowa, USA pp.
103-106
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