This investigation evaluated the cardiopulmonary effects of medetomidine, ketamine, and butorphanol anesthesia in captive juvenile Thomson's gazelles (Gazella thomsoni). Butorphanol was incorporated to reduce the dose of medetomidine necessary for immobilization and minimize medetomidine-induced adverse cardiovascular side effects. Medetomidine 40.1 ± 3.6 μg/kg, ketamine 4.9 ± 0.6 mg/kg, and butorphanol 0.40 ± 0.04 mg/kg were administered intramuscularly by hand injection to nine gazelles. Times to initial effect and recumbency were within 8 min postinjection. Cardiopulmonary status was monitored every 5 min by measuring heart rate, respiratory rate, indirect blood pressure, end-tidal CO₂, and indirect oxygen-hemoglobin saturation by pulse oximetry. Venous blood gases were collected every 15 min postinjection. Oxygen saturations less than 90% in three gazelles suggested hypoxemia. Subsequent immobilized gazelles were supplemented with intranasal oxygen throughout the anesthetic period. Sustained bradycardia (<60 beats per minute, as compared with anesthetized domestic calves, sheep, and goats) was noted in eight of nine gazelles. Heart and respiratory rates and rectal temperatures decreased slightly, whereas systolic, mean, and diastolic blood pressure values were consistent over the anesthetic period. Mild elevations in end tidal CO₂ and Pco₂ suggested hypoventilation. Local lidocaine blocks were necessary to perform castrations in all seven of the gazelles undergoing the procedure. Return to sternal recumbency occurred within 7 min and return to standing occurred within 12 min after reversal with atipamezole (0.2 ± 0.03 mg/kg) and naloxone (0.02 ± 0.001 mg/kg). Medetomidine, ketamine, and butorphanol can be used to safely anesthetize Thomson's gazelles for routine, noninvasive procedures. More invasive procedures, such as castration, can be readily performed with the additional use of local anesthetics.

A simple, reliable, and safe protocol was developed for the collection of small amounts of blood from avian eggs of variable size and at early stages of development. Fifty eggs were used in the study; 40 were common chicken (Gallus domesticus) eggs, six were homing pigeon (Columba livia domestica) eggs, and four were burrowing owl (Athene cunicularia) eggs. Collection was attempted approximately halfway through incubation. The success rate for collection of blood or blood-tinged fluid from eggs was high, averaging 68% in the chicken eggs, 100% in the homing pigeon eggs, and 75% in the burrowing owl eggs. Collection did not affect subsequent hatchability. This blood could then be used to determine the sex of the embryo by utilizing a DNA probe or restriction fragment length polymorphism technique. Sex identification in ovo allowed the demographic management of small populations of birds within our institution.

Between 1987 and 1997, we chemically immobilized 597 wild sea otters (Enhydra lutris) in Alaska for the collection of biological samples or for surgical instrumentation. One drug-related sea otter fatality occurred during this time. Fentanyl in combination with diazepam produced consistent, smooth inductions with minimal need for supplemental anesthetics during procedures lasting 30–40 min. Antagonism with naltrexone or naloxone was rapid and complete, although we observed narcotic recycling in sea otters treated with naloxone. For surgical procedures, we recommend a fentanyl target dose of 0.33 mg/kg of body mass and diazepam at 0.11 mg/kg. For nonsurgical biological sample collection procedures, we recommend fentanyl at 0.22 mg/kg and diazepam at 0.07 mg/kg. We advise the use of the opioid antagonist naltrexone at a ratio of 2:1 to the total fentanyl administered during processing.

Respiratory disease is common in captive and wild cetaceans. Bronchoscopy may permit early diagnosis of respiratory disease in dolphins and porpoises. Refinement of cetacean bronchoscopy requires development of a nomenclature system to facilitate description of the anatomic site at which lesions occur. A standard bronchoscopic nomenclature also permits serial evaluations of lesions and enhances communication between veterinarians. In this project, we adapted the bronchoscopic nomenclature devised by Amis and McKiernan for the dog and horse to the harbor porpoise (Phocoena phocoena). Silastic and air-dried models of the bronchial tree of the harbor porpoise were made to illustrate the anatomy and devise the nomenclature. Bronchial anatomy was consistent among the four porpoise lungs studied. The Amis and McKiernan nomenclature was readily adaptable to the harbor porpoise lung with minor modifications and may be useful for cetacean bronchoscopy.

An outbreak of mycoplasmosis caused by Mycoplasma alligatoris resulted in the death or euthanasia of 60 American alligators (Alligator mississippiensis) from a population of 74 captive bull alligators in Florida in 1995. The natural reservoir, routes of transmission, and host range of M. alligatoris are unknown. This study was undertaken to determine whether crocodilian species other than American alligators are susceptible to M. alligatoris. Six broad-nosed caimans (Caiman latirostris) and six Siamese crocodiles (Crocodylus siamensis) were experimentally inoculated with 10⁶ colony forming units (CFU) of M. alligatoris instilled through the glottis. Two caimans and two crocodiles were used as negative controls. Six and four American alligators were used as positive and negative controls, respectively. Three of six (50%) inoculated caimans died within 10 wk postinoculation (PI) of severe mycoplasmosis. Gross necropsy, histopathologic, and culture results were similar for broad-nosed caimans and American alligators. None of the inoculated Siamese crocodiles developed mycoplasmosis, though M. alligatoris was isolated from the tonsils in three of six (50%) animals at necropsy. All the inoculated crocodilians that survived showed significant seroconversion by 6–8-wk PI (P < 0.05). The infective dose 50% (ID₅₀) and lethal dose 50% (LD₅₀) of M. alligatoris for the broad-nosed caiman are 10⁶ CFU when instilled through the glottis, which is similar to that of the American alligator. Although the host range of M. alligatoris is not restricted to the American alligator, the organism does not appear to be pathogenic for Siamese crocodiles. Other species of crocodilians may be susceptible to infection with M. alligatoris, and this organism should be considered when the rapid onset of clinical signs of pneumonia, polyarthritis, pericarditis, and death occur.

Twenty-two free-ranging North American river otters (Lontra canadensis) from northern and eastern New York were captured and surgically implanted with radiotransmitters as part of a relocation project. The surgical technique involved an incision in the paralumbar fossa and transection through the abdominal musculature to introduce a radiotransmitter into the abdominal cavity. Two complications were encountered. Excessive hemorrhage occurred during one procedure. The otter was treated for blood loss with fluids, and it recovered uneventfully. Surgical incision infection occurred in a second animal. The otter was treated with metronidazole and enrofloxacin, and the wound was cleaned daily with chlorhexidine. The otter recovered uneventfully. Otters were released in western New York state. Postrelease monitoring via radiotelemetry revealed that the otters became established in their new ranges. The intra-abdominal implants did not affect their survival or reproductive potential.

Heparinized blood samples from 15 adult small island flying foxes (Pteropus hypomelanus) were stored at 22°C for 0-, 6-, and 24-hr intervals prior to centrifugation and separation of plasma from erythrocytes. Mean plasma biochemical values of 16 analytes were determined from all samples. Mean values of blood urea nitrogen, creatinine, total protein, albumin, globulin, alkaline phosphatase, alanine transaminase, aspartate transaminase, cholesterol, calcium, sodium, and bilirubin did not change significantly over 24 hr at 22°C. Glucose was decreased at 6 and 24 hr. Potassium and phosphorus increased and chloride decreased, respectively, between 6 and 24 hr.

Wild equids maintained in large enclosures may suffer from helminth diseases because common hygiene practices have only limited effects on parasite populations. Weekly monitoring of helminth prevalences and pasture infestation was performed for 1 yr in several extensive maintenance systems of two wildlife parks with similar climates to determine when veterinary intervention to control parasites would be useful. We also sought evidence of natural immunogenic reactions among herds of Chapman zebras (Equus quagga antiquorum), Przewalski's horses (Equus przewalskii) and dwarf donkeys (Equus asinus africanus). Fecal and vegetation samples and cultures for third-stage larvae revealed permanent egg shedding in the three species and pasture infestation during the warm, moist periods (July–September) in all enclosures. Stable social structure and low equid population density may be sufficient to make prophylaxis unnecessary in adults, whereas biotic and abiotic environmental factors such as crowding, animal transfers, social integration of subadults, and weaning stress may facilitate temporary severe infections of individuals. Biweekly helminth monitoring is a useful diagnostic tool for extensive management of exotic equids.

Carfentanil citrate was given orally to five adult brown bears (Ursus arctos) on 14 separate occasions during the winter and summer to determine effective anesthetic dosages and how season may alter these dosages. Lower blood urea nitrogen : creatinine ratios, depressed appetite, and decreased activity levels in the winter versus summer were reflective of different metabolic states, even though bears were not hibernating in the winter. Doses of carfentanil citrate between 6.0 and 15.2 μg/kg were mixed with 5–10 ml of honey, which the bears licked voluntarily from a spoon. During each anesthetization, respiratory and heart rates, hemoglobin saturation, temperature, electrocardiogram, blood gas values, and level of consciousness were monitored and utilized to determine effective dosages. Mean (±SE) dose requirements in the winter were 7.6 ± 0.4 μg/kg, whereas a greater mean dose of 12.7 ± 0.5 μg/kg was required in the summer (P < 0.05). After ingestion began, sternal recumbency occurred in an average of 7.5 min (range: 4–11 min), and full restraint and safe handling was achieved in 21 min (range: 8–40 min). At the end of each procedure, naltrexone was given as the reversal agent at a ratio of 100 mg naltrexone per 1 mg carfentanil, with 25% of the dose given i.v. or i.m. and 75% given s.c. Mean reversal time was 6 min after injection of naltrexone (range: 4–9 min). Rapid induction and recovery times and ease of oral administration make carfentanil citrate an effective anesthetic agent for use in brown bears. However, hypoventilation and respiratory acidosis were noted in all bears, and oxygen insufflation is recommended.

Flunixin (FLX) and ketoprofen (KET) are potent nonsteroidal anti-inflammatory drugs (NSAIDs) used to alleviate pain and decrease inflammation. These drugs block access of arachidonic acid to its binding site on the cyclooxygenase enzyme, thus preventing conversion to thromboxane A₂ and subsequent degradation to thromboxane B₂ (TBX). Consequently, plasma TBX may be used to estimate duration of NSAID action. Sixteen adult mallard ducks (Anas platyrhynchos) were randomly assigned to three treatment groups: control (n = 4), FLX 5 mg/kg (n = 6), or KET 5 mg/kg (n = 6). Blood samples were taken 1 hr prior to and just before (0 hr) injection and 0.25, 0.5, 1, 2, 4, 6, 12, 24, 36, and 48 hr after injection. Plasma samples were analyzed for corticosterone and TBX. The feces were tested for the presence of hemoglobin and the ducks were euthanized for complete necropsy at the end of the study. Samples of muscle, kidney, liver, proventriculus, and intestine were taken for histologic analysis. Thromboxane was suppressed significantly in all birds following administration of either FLX or KET for 4 hr and decreased for approximately 12 hr compared with baseline samples (−1 and 0 hr). In the control group, TBX gradually declined over time. None of the ducks showed evidence of gastrointestinal bleeding, but the FLX group had muscle necrosis present at injection sites. FLX and KET likely exert pharmacological effects for at least 12 h. Although degree of TBX inhibition cannot be correlated absolutely with degree of analgesia or anti-inflammatory effects, it is possible that these effects are present during this time. This work suggests that FLX and KET can potentially be used as anti-inflammatory and analgesic agents in waterfowl. However, because of muscle necrosis at the injection site, we do not recommend parenteral use of FLX in ducks.

The timing of the onset of puberty, duration of seasonal ovulatory activity, and length of postpartum anestrus were studied by means of blood plasma progesterone concentrations in a flock of European female mouflons (Ovis gmelini musimon) maintained in captivity under natural photoperiod (40°25′N). Concentrations of progesterone in the peripheral blood were determined by radioimmunoassay in samples collected from the jugular vein twice a week. First ovulations in the breeding season were highly synchronized and occurred in mid-October. In contrast, the cessation of ovulatory cycles showed significant variation among females and extended from February to May, depending on age, with 2-yr-old animals exhibiting the longest anovulatory period (P < 0.01). When lambing occurred within the breeding season (February–April), 12 out of 26 animals had their first ovulation 25 ± 1.8 days after parturition. The 14 late-lambing females had the first postpartum ovulation delayed until the next breeding season. March/April-born mouflon lambs that reached a minimum threshold body weight (23.8 ± 0.6 kg) in their first breeding season reached puberty at 8 mo of age. In those with slower growth rates, however, the prepubertal period was extended throughout the first breeding and nonbreeding seasons, reaching puberty during the breeding season of the following year at 19 mo of age and 27 ± 0.3 kg body weight. Further, attainment of puberty in ewe lambs born in June/July was also delayed until the breeding season of the following year, when animals had reached a threshold body weight at 17 mo of age.

Eight African hedgehogs (Atelerix albiventris) were presented with unilateral proptosis. Six animals presented specifically for an ocular problem, whereas two had concurrent neurologic disease. Enucleation and light microscopic examination of tissues was performed in five animals, and euthanasia followed by complete postmortem examination was performed in three animals. Histopathologic findings in all hedgehogs included orbital cellulitis, panophthalmitis, and corneal ulceration, with perforation in seven of eight eyes. The etiology of the orbital cellulitis was not determined, but it appeared to precede proptosis. Orbits in hedgehogs are shallow and the palpebral fissures are large, which may predispose them to proptosis, similar to brachycephalic dogs. This clinical presentation was seen in 15% (8/54) of African hedgehogs presented to the Western College of Veterinary Medicine over a 2-yr period from January 1995 to December 1996 and warrants further investigation.

Mycobacterium avium subsp. paratuberculosis was cultured from a single fecal sample collected from a 10-yr-old, captive-bred male addax (Addax nasomaculatus). Attempts to confirm infection with additional fecal cultures, serology, semen culture, and tissue biopsy were unsuccessful. There were no gross lesions on necropsy. On histopathology there were neither acid-fast organisms nor microscopic changes suggestive of active or clinical Johne's disease. Mycobacterium avium subsp. paratuberculosis was isolated from four organ tissues: ileum, jejunum, colon, and mesenteric lymph node.

A 9-yr and 3-mo-old captive female coati (Nasua nasua) was implanted with melengestrol acetate for contraception for 4.5 yr prior to presentation. During her annual examination, purulent vaginal discharge and a palpably prominent uterus were identified. Ancillary diagnostic tests including hematology, cystocentesis, radiographs, and abdominal ultrasound were consistent with pyometra. An ovariohysterectomy was performed and histologic examination revealed pyometra and uterine adenocarcinoma, similar to pathology that has been associated with melengestrol acetate contraception in felids, canids, and primates. Given the potential association between melengestrol acetate and uterine pathology in this case, we recommend caution with melengestrol acetate use in procyonids.

Three free-roaming Victoria crowned pigeons (Goura victoria) housed in a completely enclosed tropical exhibit were found dead without antemortem signs of illness. The birds died within 9 days of each other. Gross necropsy revealed moderate pulmonary edema in all three birds. Histopathologic examination revealed pulmonary edema and pulmonary protozoal merozoites compatible with Sarcocystis spp., Toxoplasma gondii, or Neospora spp. infection. Immunohistochemical staining for T. gondii and Neospora spp. were negative. Immunohistochemical staining identified a Sarcocystis falcatula-like parasite in all three birds. It is suspected that new exhibit soil contaminated with feces from the Virginia opossum (Didelphis virginiana) was the source of the infective sporocysts.

The clinical, gross necropsy, and histopathology findings in two unrelated desert grassland whiptail lizards (Cnemidophorus uniparens) with teratoma are described. The desert grassland whiptail is a parthenogenic lizard species with a polyploid chromosomal complement. The chromosome composition of the teratomas from these lizards was not determined.

A 14.5-yr-old, male black-and-white ruffed lemur (Varecia variegatus variegatus) presented for acute enlargement of the left testicle and hemiscrotum. Physical examination also revealed poor pelage quality with short guard hairs, sparse undercoat, and areas of alopecia. Increased aggression was also reported. A unilateral, open orchiectomy was performed, with the left testicle, epidydymis, associated vaginal tunic, and attached spermatic cord removed. Microscopic evaluation was consistent with an interstitial cell tumor, with many morphologic features similar to this neoplasm in people. No overt histopathologic criteria of malignancy were present. Following orchiectomy, gradual improvement in pelage quality was noted and was considered almost normal by 5 mo postoperative. In contrast with the aggressive preoperative behavior, the lemur was extremely submissive for 3 mo following the surgery. Gradual return to normal behavior and social status occurred over the next 2 mo. Multiple follow-up examinations and radiographs revealed no evidence of metastasis, and biopsy of the remaining testicle 4 mo later revealed no evidence of neoplasia. Serial measurements of testosterone and estradiol revealed levels within the range of those for other ruffed lemurs, as were repeated measurements taken of the remaining testicle. At 19 mo postoperative, the lemur had a coat quality considered nearly normal and maintained its historical social position in the lemur group without abnormal aggressive behavior.

A 3-mo-old male white Bengal tiger (Panthera tigris) presented with the chief complaint of regurgitation of solid food since weaning at 2 mo of age. Compared with its littermates, the tiger was in poor body condition and weighed only 10.3 kg when its littermates were estimated at 20–25 kg. Thoracic radiographs showed a megaesophagus cranial to the heart base. A contrast esophagram more clearly outlined the megaesophagus, and fluoroscopy demonstrated normal motility of the caudal esophagus. Endoscopic examination revealed a structure coursing dorsally from right to left over the esophagus and a constrictive band on the left of the esophagus at the heart base. Nonselective angiography confirmed the presence of a persistent right aortic arch, as well as an aberrant left subclavian artery. A left fourth intercostal thoracotomy was performed, and the ligamentum arteriosum was double ligated and divided. The left subclavian artery did not cause significant compromise of the esophagus and was not manipulated at surgery. The tiger recovered well from anesthesia and surgery. Solid food was slowly introduced over a 2-mo period without any regurgitation. The cub gained weight rapidly after surgery.