Taxonomy

Felids are a large group consisting of 37 species in 18 genera. There are 3 subfamilies: Felinae (which includes, but not limited to, all in genus Felis), Pantherinae (includes the genus Panthera) and the Acinonychinae, (contains a single genus, Acinonyx, the cheetah). Some species of exotic felids such as tigers, lions, bobcats (Felis rufus), caracal (Felis caracal), servals (Felis serval), and serval hybrids have become have become popular pets.

Legal Issues

All cats are either CITES I or II. All exotic felids in the pet trade should be captive bred and should have been acquired from a licensed breeder. Veterinarians should be familiar with the specific county, city, state and federal laws that determine the permit requirements for legal ownership. For example, Georgia requires either a Wildlife Exhibitor permit, or a Wild Animal License, in addition to a USDA permit. Among other things, USDA permits require a "program of veterinary care". Veterinarians are discouraged to sign on as "program veterinarians" without careful knowledge of the requirements of a program veterinarian, the facilities and husbandry and a strong client-veterinarian relationship. For more information on USDA licensing, visit http://www.aphis.usda.gov/animal_welfare/index.shtml. There are excellent reviews of exotic felid medicine in the zoo and wildlife medicine literature that are considered "standard veterinary care" for these species and with which practitioners should be familiar.¹⁰

Safety & Restraint

Exotic felids come armed with large teeth and claws and powerful limbs. They are agile, quick and find it easy to free themselves from physical restraint. The staff should be aware of how to handle these animals when they present to the clinic. Animals should be presented in adequate carriers and in a manner in which they can be removed from the container if needed. Most felids are easy to train and positive training methods (i.e.: clicker training) can be used to manage these animals. This will minimize the stress associated with veterinary care and, in some cases, aid in simple veterinary procedures (standing on scale, venipuncture from tail, opening mouth for exam, etc.). Small felids (<10 kg) can be physically restrained (with the help of a net and gloves) for hand-injection of anesthetic agents. With few exceptions, a thorough physical exam cannot be performed on a conscious animal under physical restraint. Squeeze cages are useful for larger cats. In some cases, such as tigers in an outdoor enclosure, administration of anesthetics may only be possible with pole syringes or via darts.

Husbandry

Exotic felids require large spaces to allow them to display a range of natural behaviors related to foraging and territoriality. Most felids are solitary, but some are social (lions) or can adapt to small groups (especially if sterilized). All felids are good climbers, swimmers and jumpers. Some felids are arboreal and require vertical space in order to feel secure. Adequate fencing and other containment facilities are part of all permitting requirements. Large outdoor enclosures are preferred as they allow exercise, exposure to ultraviolet light, the maintenance of natural circadian rhythms and improved ventilation. Problems associated with outdoor enclosures include traumatic injuries from other animals (i.e.; feral dogs), escape, vandalism/theft, and exposure to feral cats. Many exotic pet felids are kept 100% indoors. When housed outdoors, the substrate should be easy to clean; however, felids housed on concrete flooring often suffer from chronic degenerative joint problems and food pad ulcerations. A mixture of substrates is ideal.

Nutrition

Small cats should receive 4 to 8% percent of their body weight daily. Large cats require only 1.5 to 3 percent of their body weight in food daily. However, young growing cats may require 10 - 25% of their body weight in food each day. Non-domestic fields are prone to obesity in captivity and therefore, it is best to keep them at a "lean" body weight. Exotic felids are carnivores. The domestic cat can be used as a similar physiologic model. Diets aimed for exotic felids should contain products that are high in quality and prepared with hygienic standards. Salmonellosis and other bacterial enteritis have been reported in cats fed diets that were not handled appropriately.^2,8 Diets prepared for felids should be balanced. Muscle meat alone can lead to secondary nutritional hyperparathyroidism. Many balanced commercial diets are available for felids and should be used as the base of the diet; however, they do not promote natural feeding behaviors. Other items, such as large bones (that can be chewed but not swallowed), small prey, or animal hides can serve to enrich these behaviors. If a home diet is prepared, a minimum of 1% calcium and taurine supplementation is required. Examples of companies that provide balanced commercial diets: Dallas Crown Horse Meat-Based Frozen Carnivore Diet, Nebraska (Animal Spectrum Inc.) Premium Canine and Feline Diets, Milliken Toronto Zoo Feline/Canine Diets, and Natural Balance Zoo Carnivore Diet. Frozen meat diets are usually the diet of choice at most zoos and larger institutions. Dry diets have been shown to be nutritious, but cats may shun them due to their texture or palatability. Mazuri (Purina) and Eukanuba are good dry diets for exotic cats.

Anesthesia

Anesthesia of exotic felids is fairly straightforward. The same principles used in domestic cat medicine apply. A recent review offers a more comprehensive resource for practitioners working with exotic felids including an exhaustive reference list.⁴ Pre-anesthetic fasting for 12 hrs is recommended. As a general rule, keeping the animal stress-free or relatively calm will translate to needing to use less anesthetic and provide a smoother anesthetic induction. There are a variety of protocols that have been reported for exotic felid anesthesia. In general, the protocols designed for domestic cats are applicable; however, there are some exceptions. Telazol should not be administered to tigers as it can induce seizures and death. Common injectable agents used in non-domestic felids include: ketamine / xylazine; ketamine, /xylazine,/ diazepam, ketamine/diazepam, ketamine / medetomidine; or medetomidine alone. The reader is referred to the References section for references on specific dosages. Inhalant gas induction, without previous pre-medication, are not recommended. Alpha-2 agonists can induce heaving and/or vomiting in most cats. Once induced, isoflurane or sevoflurane in 100% O2 can be utilized to maintain anesthesia. When referring to published drug dosages, it is useful to know if the animal was free-ranging or captive, if the protocol was utilized only to render an animal recumbent for subsequent intubation and inhalant anesthesia, or if the dosage was used to achieve immobilization throughout the animal handling procedure (i.e.: field anesthesia). Anesthesia monitoring should be performed in the same manner as with domestic cats.

Surgery

Often owners request de-clawing, canine teeth extractions and other surgical procedures aimed to make it "more convenient" to own exotic felids. I strongly disagree with these procedures, as they are not performed for the benefit of the animal, and in most cases, can interfere with the animal's natural behavior and cause secondary health problems. The following is a direct quote from Dr. Laurie Gage (USDA Large Felid Specialist): "The problem with most declawing techniques is that P-3 is damaged or removed with the claw. That leaves the cat with P-2 bumping abnormally into the pad for the rest of its life. Usually after about 10 years of age, these cats, the larger of which may reach an adult weight of over 200 kg, will tend to walk back on the posterior portions of their feet, avoiding the pressure of walking normally on their toes. They are prone to pad ulcerations, they tend to gradually develop arthritis in other joints from walking abnormally, have been known to develop back problems, and they almost always seem foot-sore. Cats use their claws for balance and for grasping. They derive a certain amount of enrichment from using their claws. Depriving them of their claws because they have an owner that has no idea of how to handle or manage them seems unjustified. Ovariohysterectomy and castration can be accomplished as in the domestic cat and have also been described utilizing minimally-invasive techniques;^1,6 however, in some species vasectomies are preferred as they do not interfere with secondary sexual characteristics (i.e.: manes in lions) or social behavior. When performing a vasectomy, it is wise to submit the resected vas deferens for histopathologic confirmation.

Preventative Medicine

Preventative medicine should include all aspects of husbandry and nutrition. Veterinarians should review the husbandry practices used to keep these animals and physically examine exotic felids at least annually. Conditions that can be identified are dental disease, osteoarthritis, spondylosis and chronic renal failure. Quarantine methods should be applied (at least 30 days without contact). If the owner is breeding, further consideration should be given to the preventative medicine of kittens (same schedule of examination, vaccination and deparasitizing). The following preventative medicine protocol is the minimum needed:

Annual Physical Exam

Annual baseline blood work (CBC, Biochemistry, Urinalysis).

If this is the first visit, or if the risk factors dictate it (i.e.: exposure to feral cats), blood collection for:

 Feline leukemia, Feline immunodeficiency virus testing (Cornell University Animal Health Diagnostic Laboratory, Ithaca, NY)

 Feline infectious peritonitis testing (Washington Animal Disease Diagnostic Laboratory, Pullman WA)

Note: domestic cat test kits are not appropriate for non-domestic felid disease testing and the reader is referred to the current zoological medicine literature for specific testing recommendations.¹⁰

Annual fecal exam (more frequent if housed outdoors and especially if exposed to other felids).

Vaccination with:

 Feline rhinotracheitis

 Feline calicivirus

 Feline panleukopenia

 Rabies

1 ml SQ of a killed virus vaccine should be given at least at 9, 12 and 16 wks of age and considered annually; however, due to concerns over vaccine-associated sarcomas may dictate that vaccine titers may be examined annually and a decision made to vaccine based on risk, exposure to other cats and antibody titers. A canary-pox vectored subunit vaccine should be used to vaccinate felids against canine distemper.³ This disease has killed several captive felids. Canine distemper vaccines (modified or killed) should NOT be used to vaccinate felids, but can use subunit canarypox vaccine by Merial if risk of exposure to raccoons or domestic dogs exists. Vaccination against feline leukemia or FIV is not recommended at this time, but has been used in some zoological collections to manage situations where these diseases where a problem. Other vaccines that have been reported for use in non-domestic Felids: Chlamydophila vaccine, Dermatophyte vaccine in collections where these diseases were a problem.

Exotic felids, like their domestic counterparts, are susceptible to canine heartworm and should receive preventative in the same frequency and dose.

Other Diseases

In addition to the diseases mentioned above, the following have been reported in exotic felids:

 Feline Upper Respiratory Disease Complex--caused by a combination of organisms including rhinotracheitis, chlamydia, herpesvirus, and calicivirus.

 Gastritis is commonly seen in cheetahs, caused by a Helicobacter bacteria and captivity-associated stress.

 Pyloric stenosis (tigers only) which have required surgical Z-Y plasty to repair the problem and have recovered uneventfully.

 Metabolic bone disease is still reported in young growing exotic felids due to diets with inadequate levels of calcium and lack of exposure to sunlight.

 Ethylene glycol poisoning was reported in cats fed a particular commercial diet emphasizing that commercial diet quality should be carefully monitored.

 Intervertebral disk rupture occurs in large cats and is diagnosed and treated in the same manner. Mostly reported in tigers.

 Veno-occlusive disease of cheetahs and snow leopards. This is a slowly progressing disease of the liver that results in the fibrosis of the hepatic sinusoids. Clinical signs relate to liver failure. There are a variety of diseases associated with cheetahs and veterinarians who plan to work with this species should build a library of articles and books on the subject.

 Bovine spongiform encephalopathy was reported in felids in Europe. Imported non-domestic felids that have been fed cattle carcasses might be at risk for developing BSE.

 Neoplasia is not uncommon and several isolated reports exist in the literature, mostly on lymphoma and reproductive tumors associated with contraceptives.^4,7

References

1.  Aguilar, R.F., S.K. Mikota, J. Smith, L. Munson, L.J. Freeman and R. Kolata. 1997. Endoscopic ovariohysterectomy in two lions (Panthera leo). JZWM. 28(3): 290-297.

2.  Clyde, V.L., E.C. Ramsay, and D.A. Bemis. 1997. Fecal shedding of Salmonella in exotic felids. JZWM 28 (2): 148-152.

4.  Deem, S.L., L. H. Spelman, R.A. Yates and R. J. Montali. 2000. Canine distemper in terrestrial carnivores: A review. JZWM 31 (4): 441-451.

5.  Gunkel, C., and M. LaFortune. 2007. Felids. In: West, G., D. Heard and N. Caulkett. Zoo Animal & Wildlife Immobilization and Anesthesia. Blackwell Publishing, Ames, Iowa. Pp.443-458.

6.  Harrestein L., L. Munson, U.S. Seal, G. Riggs, M. R. Cranfield, L. Klein, A. W. Prowten, D. D. Starnes, V. Honeyman, R. P. Gentzler, P. P. Calle, B. L. Raphael, K. J. Felix, J. L. Curtin, C. D. Page, D. Gillespie, P. J. Morris, E. C. Ramsay, C. E. Stringfield, E. M. Douglass, T. O. Miller, B. T. Baker, N. Lamberski, R. E. Junge, J. W. Carpenter and T. Reichard. 1996. Mammary cancer in Captive Wild Felids and Risk Factors for its Development: A retrospective study of the clinical behavior of 31 cases. JZWM 27 (4): 468-476. 

7.  Kolata, R.J. 2002. Laparoscopic ovariohysterectomy and hysterectomy on African lions (Panthera leo) using the UltraCision harmonic Scalpel. JZWM 33 (3): 280-282.

8.  Kazensky, C. A., L. Munson, and U. S. Seal. 1998. Effects of MA implants on Exotic Felids. JZWM 29 (1): 1-5.

9.  Lewis, C.E., D.A. Bemis, and E.C. Ramsay. 2002. Positive effects of diet change on shedding of Salmonella spp. in the feces of captive felids. JZWM 33 (1): 83-84.

10. Miller, M., M. Weber and D. Neiffer, et al. 2003. Anesthetic induction of captive tigers (Panthera tigris) using a medetomidine-ketamine combination. JZWM 34 (3): 307-308.

11. Wack, R.F. Felidae. 2003. In: Fowler, M.E. and R.E. Miller. (eds.) Zoo & Wild Animal Medicine, 5th ed. Saunders Co., St. Louis, Missouri. Pp. 491-501.