Christopher J. Dutton

BIOMEDICAL EVALUATION OF FREE-RANGING RING-TAILED LEMURS (LEMUR CATTA) IN TSIMANAMPETSOTSA STRICT NATURE RESERVE, MADAGASCAR

Abstract Complete health assessments were performed on 20 adult ring-tailed lemurs (Lemur catta), 10 males and 10 females, free ranging within the Tsimanampetsotsa Strict Nature Reserve in southwest Madagascar. Each animal was anesthetized using tiletamine and zolazepam, weighed, and given a thorough physical examination. Blood was collected for hematology, determination of plasma total protein concentration, serum chemistry, determination of fat-soluble vitamin and trace mineral concentrations, assessment of iron metabolism, toxoplasmosis and viral serologies, and examination for parasites. Feces were collected for bacterial culture and parasite examination, and representative numbers of ectoparasites were collected. Blood values differed significantly in a number of ways from values in captive lemurs, possibly associated with recent food consumption, hydration, and diet. There was no evidence of serious infectious disease and no hemoparasites. The enteric flora appeared unremarkable, although results may have been skewed toward cold-tolerant bacteria. The fecal parasite burden was low, but there were large numbers of ectoparasites (mites) present. Our study demonstrated that a substantial amount of data can be collected from free-ranging populations, information that is invaluable in the management of captive populations, particularly with regard to disease, and in assessing risks associated with reintroduction programs.

Biomedical Evaluation of Free-Ranging Red Ruffed Lemurs (Varecia rubra) Within the Masoala National Park, Madagascar

Abstract Complete health assessments were performed on 22 adult red ruffed lemurs (Varecia rubra), comprising nine males and 13 females, found within the Masoala National Park in northeast Madagascar. Each animal was anesthetized using tiletamine and zolazepam and underwent a thorough physical examination, including measurement of its weight and vital signs; blood collection for hematology, plasma total protein concentration, serum chemistries, fat-soluble vitamins, trace minerals, assessment of iron metabolism, toxoplasmosis serology, viral serologies, and examination for hemoparasites; fecal collection for bacterial culture and parasite examination; and collection of a representative number of any ectoparasites. Comparison of blood values with those of captive lemurs demonstrated a number of significant differences thought to be associated with physiologic state (e.g., reproductive stage and stress), hydration, and diet. There was no evidence of serious infectious diseases, and hemoparasites were not detected. The enteric flora appeared unremarkable; however, results may have been skewed toward more cold-tolerant bacteria. The fecal parasite burden was low. Lemurostrongylus spp. was identified in two of the lemurs, and there were moderate numbers of Laelapidae mites present on approximately one third of the lemurs. This study demonstrated the substantial amount of data that can be collected from free-ranging populations, considered invaluable in the management of captive populations, in reducing the incidence of captivity-related diseases, and in the risk assessment associated with reintroduction programs.

Comparison of Biomedical Evaluation for White-Fronted Brown Lemurs (Eulemur fulvus albifrons) from Four Sites in Madagascar

Abstract Health and nutritional assessments of wildlife are important management tools and can provide a means to evaluate ecosystem health. Such examinations were performed on 37 white-fronted brown lemurs (Eulemur fulvus albifrons) from four sites in Madagascar. Comparison of health parameters between sites revealed statistically significant differences in body weight, body temperature, respiratory rate, hematology parameters (white cell count, hematocrit, segmented neutrophil count, and lymphocyte count), serum chemistry parameters (aspartate aminotransferase, alanine aminotransferase, serum alkaline phosphatase, total protein, albumin, phosphorus, calcium, sodium, chloride, and creatinine phosphokinase), and nutrition parameters (copper, zinc, ferritin, retinol, tocopherol, and 25-hydroxycholecalciferol). Two of 10 lemurs tested were positive for toxoplasmosis; none of 10 were positive for Cryptosporidium or Giardia. Enteric bacteria and endo- and ectoparasites were typical. Statistically different values in hematology and chemistry values probably do not reflect clinically significant differences, whereas nutrition parameter differences are likely related to season, soil, and forage availability.

A COMPARISON BETWEEN PRE- AND POSTHIBERNATION MORPHOMETRY, HEMATOLOGY, AND BLOOD CHEMISTRY IN VIPERID SNAKES

Abstract Snakes from temperate climates are often made to hibernate in zoos to stimulate reproduction. Unfortunately, deaths have occurred during and after hibernation. This study evaluated the health status, pre- and posthibernation, of 31 adult viperid snakes. It included morphometric measurements, hematology, and blood chemistry. No differences were seen in body weights and weight to length ratios between pre- and posthibernation examinations, suggesting that the overall condition of the snakes did not change. No differences were seen in hematologic and blood chemistry parameters, except that bile acids (3α-hydroxybile acids) decreased, the implications of which are unknown. Three individuals had markedly high plasma uric acid levels posthibernation; of these, two individuals died from extensive visceral gout and one recovered with fluid therapy. Viperid snakes should be clinically healthy, well hydrated, and in good body condition when they are put into hibernation. They should be maintained in an environment with sufficient humidity and should have access to water. Blood samples should be collected on arousal for measuring plasma uric acid levels. Changes in morphometry, hematology, and blood chemistry appear to be abnormal and should be investigated thoroughly.

Paraparesis in a Polar Bear (Ursus maritimus) Associated with West Nile Virus Infection

Abstract A polar bear (Ursus maritimus) housed at the Toronto Zoo presented with acute-onset, nonambulatory paraparesis. Physical examination 24 hr after onset was otherwise unremarkable, spinal radiographs looked normal, and blood tests indicated mild dehydration. With continued deterioration in its general condition, euthanasia was elected a day later. Necropsy did not reveal a cause for the major presenting clinical signs. Serum collected at the time of initial examination was positive for West Nile virus (WNV) antibodies in a serum neutralization assay and at the time of euthanasia was positive in both a competitive enzyme-linked immunosorbent assay and in a plaque reduction neutralization assay. The major microscopic finding was a mild-to-moderate nonsuppurative meningoencephalomyelitis. WNV was not detected by immunohistochemistry in brain or spinal cord or by real-time reverse transcription-polymerase chain reaction (RT-PCR) and cell culture of brain and kidney, but it was isolated and identified by RT-PCR in second passage cell culture of spleen. Retrospective immunohistochemistry on spleen revealed rare antigen-positive cells, probably macrophages. Prevention of exposure to potentially WNV-infected mosquitoes or vaccination of captive bears against WNV should be considered.

Neoplasia of Captive Yellow Sea Horses (Hippocampus kuda) and Weedy Sea Dragons (Phyllopteryx taeniolatus)

Abstract:u2003 Syngnathidae is the family of fish that includes sea horses, pipefish, and sea dragons. To date, only a single publication has described neoplasia in syngnathids, a fibrosarcoma of the brood pouch in an aquarium-reared lined sea horse (Hippocampus erectus). From 1998 until 2010, the Toronto Zoo submitted 172 syngnathids for postmortem; species included the spotted or yellow sea horse (Hippocampus kuda), the pot-bellied sea horse (Hippocampus abdominalis) and the weedy sea dragon (Phyllopteryx taeniolatus). Seven neoplasms and two neoplastic-like lesions were identified from these cases. Under light microscopy, the neoplasms had morphological characteristics of a cardiac rhabdomyosarcoma, renal adenocarcinoma, renal adenoma, renal round cell tumors, which were likely lymphomas, exocrine pancreatic carcinoma, and intestinal carcinoma. Of these neoplasms, four had clear evidence of metastasis: the pancreatic and intestinal carcinomas and both round cell tumors. As syngnathids are highly fastidious animals, they can be difficult to maintain in captivity. In order to improve their husbandry, preventative and palliative care, as well as treatment, it is important to investigate and document the types of diseases affecting syngnathids.

A MODIFIED PROTOCOL FOR SEX IDENTIFICATION OF IN OVO AVIAN EMBRYOS AND ITS APPLICATION AS A MANAGEMENT TOOL FOR ENDANGERED SPECIES CONSERVATION PROGRAMS

Abstract 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.

Sarcomatoid carcinoma in the lung of an Egyptian fruit bat (Rousettus aegyptiacus).

A sarcomatoid carcinoma was diagnosed in the lung of a 10-year-old captive Egyptian fruit bat (Rousettus aegyptiacus). Both carcinomatous and sarcomatous cytologic phenotypes were identified histologically. Cells of both types stained positive for pancytokeratin and S-100. Stromal cells stained positively for muscle actin. No staining for vimentin was noted in either neoplastic or normal internal control tissues. To the authors knowledge, this is the first report of a pulmonary sarcomatoid carcinoma in a bat, and only the third report of sarcomatoid carcinoma outside the human literature.

HYDROMYELIA IN A REEVES' MUNTJAC (MUNTIACUS REEVESI)

Abstract A 24-day-old, 2.2-kg, female Reeves muntjac (Muntiacus reevesi) acutely developed left hind limb lameness that resolved with rest and anti-inflammatory drugs but recurred at 8 mo of age. Magnetic resonance imaging (MRI) of the lumbar, sacral, and coccygeal spine revealed a fluid-filled dilatation of the central canal of the spinal cord, which was interpreted as a hydromyelic cyst. Surgical exploration and drainage of the cyst were attempted. Despite initially improved mobility, severe plantar ulceration of both hocks developed. The animal was euthanatized. Gross necropsy of the central nervous system revealed a 1.5-cm-long, mild depression with associated yellowing of the dorsal spinal cord in the lumbosacral region, dilatation of the central spinal canal that extended from the cranial thoracic spinal cord with diameter increasing caudally, and mild herniation of the brainstem at the foramen magnum. Histopathologic lesions of the central nervous system were restricted to the spinal cord, with equivocal enlargement of the fourth ventricle. Pathologic changes included irregular dilatation of the central canal, flattening to the absence of the ependymal cells, spongiosis of the gray matter neuropil, and dystrophic calcification. The gross and histologic findings confirmed the diagnosis of hydromyelia.

XY MALE PSEUDOHERMAPHRODITISM IN A CAPTIVE ARABIAN ORYX (ORYX LEUCORYX)

Abstract A 2-yr-old Arabian oryx (Oryx leucoryx) was presented for evaluation of abnormal genitalia and infantile behavior. The oryx had a penis and a scrotum, but testes were not palpable within the scrotum or inguinal canal. The total serum testosterone for the individual was lower than in age-matched males of the same species. Surgical exploration showed markedly hypoplastic intra-abdominal gonads, which demonstrated both testicular and uterine tissue on histologic examination. After karyotype analysis, the individual was classified as an XY male pseudohermaphrodite. This condition resembles two human intersex syndromes: embryonic testicular regression syndrome and partial gonadal dysgenesis syndrome, which occur in familial lines.