The transmissible spongiform encephalopathies (TSEs) represent an emerging group of diseases that have been labeled as “prion diseases” because of the recent characterization of the infectious agent. TSEs are caused by prions, which induce neurodegenerative fatal diseases in humans and animals. Some TSEs (scrapie and kuru), have existed in both animals and humans for a very long time, whereas others such as bovine spongiform encephalopathy and variant Creutzfeld–Jakob disease have either recently emerged or are more thoroughly described and recognized. It is obvious that the medical community will be forced to consider these diseases in humans and animals for the future. This article offers a short review of the TSEs of immediate concern to zoo and wildlife veterinarians and wildlife biologists and suggests risk management strategies for the prevention of these diseases, with special focus on chronic wasting disease of cervids in North America.

Alpha₂ agonists are commonly used in combination with other anesthetic agents to chemically immobilize wildlife and may cause potentially serious hypoxemia in wild ruminants. In some domestic ruminants, they are associated with significant changes to the pulmonary parenchyma, increased venous admixture, pulmonary edema, and hypoxemia. Effective and safe immobilization of these animals requires knowledge of the mechanisms behind these changes and the methods that offset their effects, including the use of supplemental oxygen.

This study was undertaken to determine whether Haemobartonella felis (Mycoplasma haemofelis), the causative bacterial agent of feline infectious anemia, infects nondomestic cats. Routine complete blood count and polymerase chain reaction (PCR) were performed to detect the gene for 16S ribosomal RNA for the organism. Sixty-four blood samples were collected from 54 nondomestic cats, including tigers (Panthera tigris), cheetahs (Acinonyx jubatus), lions (P. leo), mountain lions (Felis concolor), snow leopards (P. unica), and a jaguar (P. onca). Some cats were sampled on two or three different dates. Two tigers were positive for H. felis by PCR analysis. As previously described in domestic cats, the parasitemia appears to be intermittent in nondomestic cats.

Tendon ossification in the crus and tarsometatarsal regions of cranes makes ultrasonography difficult everywhere except for joints, where ossification is absent. Normal ultrasonographic anatomy of the adult Florida sandhill crane (Grus canadensis pratensis) intertarsal joint is described on the basis of ultrasonography that was performed on the limbs of a cadaver, which were dissected and cross-sectioned subsequently, to correlate ultrasonographic images with anatomic structures. Intertarsal joints of five normal sandhill cranes and two cranes with known intertarsal abnormalities were then imaged bilaterally in transverse and sagittal planes. Ultrasonographic imaging can be used to evaluate the soft-tissue structures on the dorsal and plantar aspects of the intertarsal joint of cranes, and it is a useful adjunct to physical and radiographic examination for localizing injuries to this area.

Parenteral anesthetic protocols for short-term immobilization were evaluated in twenty 4-yr-old Gulf of Mexico sturgeon (Acipenser oxyrinchus de soti). An initial dose–response trial determined the efficacy of either propofol (3.5–7.5 mg/kg, i.v.) or combinations of medetomidine (0.03–0.07 mg/kg, i.m.)–ketamine (3–7 mg/kg, i.m.). A subsequent study evaluated the physiologic effects of propofol (6.5 mg/kg, i.v.)-induced anesthesia and anesthesia induced with a medetomidine (0.06 mg/kg, i.m.)–ketamine (6 mg/kg i.m.) combination. The effects of medetomidine were reversed at 30 min with atipamezole (0.30 mg/kg, i.m.). Both drug protocols provided adequate short-term immobilization for minor diagnostic procedures. Sturgeon receiving propofol were in a light plane of anesthesia within 5 min after drug administration, whereas only 30% of the medetomidine–ketamine group reached a light plane of anesthesia in the same time period. Both propofol and medetomidine–ketamine resulted in mild bradycardia and apparent respiratory depression, with propofol producing more profound effects. At the dosages used in this study, both propofol and the medetomidine–ketamine combination effectively induced a light plane of anesthesia. Induction times were shorter in the propofol group.

Individuals of two porcupine species (Coendou prehensilis and Coendou melanurus) were translocated during the flooding of a forest at a hydroelectric dam site in French Guiana. Blood samples were collected for 11 mo to determine hematologic and serum chemistry reference mean values and ranges and to look for blood parasites. Male C. prehensilis had significantly higher hemoglobin levels, packed cell volumes, and creatinine and potassium values than did females of the same species. Coendou prehensilis had significantly lower amylase levels but higher creatinine, calcium, lactate dehydrogenase, and gamma glutamyl transferase levels than C. melanurus.

The relative efficacies and cardiorespiratory effects of three injectable anesthetic combinations containing medetomidine were evaluated in ring-tailed lemurs (Lemur catta). In addition, the direct effects of medetomidine on heart rate and blood pressure were evaluated in lemurs anesthetized with isoflurane. For injectable anesthesia, captive adult ring-tailed lemurs were anesthetized with medetomidine and ketamine (0.04–0.06 mg/kg, i.m. and 3 mg/kg, i.m., respectively), medetomidine, butorphanol, and ketamine (0.04 mg/kg, i.m., 0.4 mg/kg, i.m., and 3 mg/kg, i.m., respectively), or medetomidine, butorphanol, and midazolam (0.04 mg/kg, i.m., 0.4 mg/kg, i.m., and 0.3 mg/kg, i.m., respectively). For inhalation anesthesia, lemurs were mask-induced and maintained with isoflurane for 30 min before receiving medetomidine (0.04 mg/kg, i.m.). Sedation produced by medetomidine–ketamine was unpredictable and of short duration. Both medetomidine–butorphanol–ketamine (MBK) and medetomidine–butorphanol–midazolam (MBMz) provided adequate anesthesia for routine physical exams; however, the effects of MBMz lasted longer than those of MBK. Heart rates and respiratory rates were within clinically normal ranges for all groups, and lemurs remained normotensive throughout the study. Common side effects such as hypertension and bradycardia associated with the use of α₂-adrenergic receptor agonist combinations in other species were not observed. Likewise, medetomidine administration had no effect on HR in lemurs receiving isoflurane. Lemurs in all groups were well ventilated and remained well oxygenated throughout the procedures, though arterial partial pressure of O₂ was lowest in the MBMz group. All three injectable medetomidine combinations were effective in ring-tailed lemurs but only MBK and MBMz provided adequate depth and duration of anesthesia for use as sole regimes. For many clinical procedures in lemurs, MBMz offers advantages over MBK because of its longer duration of action and its rapid and more complete reversibility with specific antagonists.

Pharmacokinetic studies of antifungal agents in reptiles are uncommon. Itraconazole, which has been used prophylactically in juvenile sea turtles suffering from hypothermia (cold stunning) on a regular basis, was evaluated for steady-state plasma concentrations. Five Kemp's ridley sea turtles (Lepidochelys kempi) receiving itraconazole at several dosages in a rehabilitation program had blood collected within 24 hr to estimate dosing frequency. Subsequently, serial blood samples of Kemp's ridley sea turtles that were given itraconazole at several dosages for 30 days to treat cold stunning were collected at various intervals to evaluate itraconazole plasma concentrations. Tissue samples were collected from one Kemp's ridley that died during rehabilitation. Plasma concentrations of itraconazole (and of hydroxyitraconazole [OH-ITRA], one of its major bioactive metabolites) were determined using a modified, validated reverse-phase high-performance liquid chromatography technique. Itraconazole concentrations in tissues were determined by bioassay to be far greater than the plasma concentrations measured in any of the turtles. At a 15-mg/kg dosage, the half-life (t_1/2) was 75 hr for itraconazole and 55 hr for OH-ITRA. All dosages produced adequate concentrations in some turtles, but consistent therapeutic concentrations were produced only at 15 mg/kg q72hr and 5 mg/kg s.i.d., with the latter producing the highest plasma concentrations.

A 12-yr-old mountain lion (Felis concolor) developed a 0.5-cm³ raised nonpigmented and nonulcerated mass between the lip and the nasal planum. The tumor was surgically removed and diagnosed histologically as a fibropapilloma. The tumor recurred 1 yr later, at which time it was again excised, and the diagnosis was reconfirmed by biopsy. Frozen tissue from the second excision was submitted for polymerase chain reaction testing for papillomavirus. The 176–base pair polymerase chain reaction product recovered from the tumor was cloned and sequenced. The papillomavirus had 96% homology with a papillomavirus previously retrieved from a fibropapilloma in a domestic cat and is the next most closely related to bovine papillomavirus type 1. This is the first report of a virus-associated fibropapilloma in a mountain lion.

Two male Florida manatees (Trichechus manatus latirostris) died at the marine aquarium in Inagi City, Tokyo, Japan. Acid-fast bacteria were demonstrated in tuberculoid nodules in the lungs from both manatees. Mycobacterium marinum and M. fortuitum were isolated from one manatee; M. marinum and M. kansasii were cultured from the second animal. This report confirms the pathogenicity and potentially fatal outcome of mycobacterial infection in manatees. In addition, the pathologic response to infection with these mycobacteria in manatees is similar to that associated with Mycobacterium spp. in other animals.

Serial IgG antibody titers to Toxoplasma gondii from three juvenile great grey kangaroos (Macropus giganteus giganteus) with clinical signs consistent with toxoplasmosis were compared with titers from three clinically normal juveniles of similar age. The modified agglutination test was used to measure antibodies to T. gondii. Results demonstrated declining antibody titers to T. gondii in five of six animals. Antibody titers were similar in animals with and without clinical signs. This was interpreted as an indication that maternal IgG antibodies to T. gondii were transferred to juveniles, presumably in milk, rather than an indication of clinical disease. Therefore, clinicians should interpret Toxoplamsma serology results in juvenile macropods cautiously.

A 10-mo-old female eland (Taurotragus oryx) at the Wilds exhibited recalcitrant, progressive unilateral uveitis for a 5-wk period, despite constant medical treatment. Unilateral enucleation was performed because of blindness and animal discomfort evidenced by continuous blepharospasm. Histopathologic examination of the eye demonstrated intraocular larvae morphologically consistent with Parelaphostrongylus tenuis, the first known case of intraocular P. tenuis migration. This animal subsequently was euthanatized because of severe, nonresponsive neurologic signs associated with P. tenuis infection.

A mature male and a mature female Dirofilaria immitis were found in the right ventricle of the heart of a naturally infected 2-yr-old male Eurasian otter (Lutra lutra) that had died of severe lung congestion at a zoo in South Korea. Both developing embryos and microfilariae were present in the uterus of the female D. immitis. Although circulating microfilariae were not detected in blood or tissue, the Eurasian otter may serve as a definitive host for D. immitis.

A mixture of medetomidine (50.0 μg/kg, i.m.) and zolazepam–tiletamine (2.0 mg/kg, i.m.) effectively immobilized 16 sun bears (Helacrtos malayanus) for more than 1 hr with good myorelaxation and minimal effects on cardiorespiratory performance during 22 immobilizations. All bears were immobilized once, except for six individuals that were immobilized twice. Atipamezole (250 μg/kg, i.v.) effectively reversed medetomidine-induced sedation and reduced recovery time significantly. Respiratory rates of immobilized bears did not change significantly over time. Rectal body temperature and heart rate decreased significantly after 10 min of immobilization. Hematologic and serum biochemical parameters did not change significantly within 30 min of induction.

Simple nonlethal blood culture methodology, an alternative to euthanasia for diagnosing systemic bacterial infections in fish, is described. Blood was extracted from the caudal vein of 20 individuals of five fish species, incubated in brain–heart infusion broth, and then plated onto enriched blood agar. Nine of these fish were subsequently euthanized and necropsied for confirmatory tissue cultures. Five species of bacteria were isolated from the blood cultures from nine fish, and the tissue culture results in euthanized, necropsied fish agreed with the blood culture results in all cases. All the fish that were not euthanized survived for 24 hr, although two heavily parasitized fish subsequently died.