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Mixed germ cell tumours occur rarely in veterinary species. This report describes a case of metastatic mixed germ cell tumour in a female Eurasian harvest mouse (Micromys minutus). The tumour was extensive in one ovary and the uterus, and was characterized by two distinct tumour cell populations with features typical of embryonal carcinoma (EC) and choriocarcinoma (CC). Metastases of CC to the lungs and liver were observed. The exact origin of the CC was unclear, but the possibility of a non-gestational CC is favoured, given the context of a mixed germ cell tumour and lack of p53 expression. EC diagnosis was confirmed by immunohistochemical labelling of CD30 and lack of immunoreactivity for c-Kit. In addition, membranous β-catenin expression was present in the EC component, indicating an inactive Wnt/β-catenin pathway, which is required for the maintenance of pluripotency.

The protozoan parasite Sarcocystis neurona is an important cause of disease in horses (equine protozoal myeloencephalitis, EPM) and marine mammals. Isolated reports of clinical EPM-like disease have been documented in a zebra, raccoon, domestic cat, domestic dog, ferret, skunk, mink, lynx, red panda and fisher. The predominant disease is encephalomyelitis associated with schizonts in neural tissues. Here, we report highly disseminated sarcocystosis, in many tissues of a captive White-nosed coati (Nasua narica molaris). The 14year old, neutered male coati was euthanized due to progressive weakness, lethargy, and inappetence. Schizonts, including free and intracellular merozoites were detected in many cell types, and differed morphologically from S. neurona schizonts in horses. Only a few sarcocysts were seen in skeletal muscle and the myocardium. Immunohistochemically, the protozoa reacted positively to S. neurona but not to Toxoplasma gondii antibodies. Severe inflammtory disease detected in the stomach, intestine, adrenal and thyroid glands, ciliary body of eye, and urinary bladder associated with schizonts in the coati has not been reported earlier in any host with EPM. Although, a few schizonts were found in the brain, encephalitis was minimal and not the cause of clinical signs. Multilocus PCR-DNA sequencing using DNA derived from the coati lung tissue identified an S. neurona infection using the 18S, 28S and ITS-1 markers, and a novel genotype using primer pairs against antigenic surface proteins (SnSAG3, SnSAG4, SnSAG1-5-6) and microsatellite markers (MS, SN7, SN9). Although the genotype was similar to the widely distributed Type VI strain, it possessed a novel allele at SnSAG5, and a different MS combination of repeats at SN7 and SN9. Whether this severe parasitism was related to the host or the parasite needs further investigation.

The protozoan parasite Sarcocystis falcatula is an important cause of clinical disease in several avian intermediate hosts. The host range of S. falcatula is wide, and numerous outbreaks of acute sarcocystosis have been reported in passerine and psittacine birds in captivity in the Americas. Previous diagnosis was performed by serologic methods, light, and/or electron microscopic examinations with limited molecular confirmation. Here, we report histological and molecular diagnosis of acute, fatal S. falcatula infections in rainbow lorikeets ( Trichoglossus moluccanus) at the Philadelphia Zoo. Pulmonary sarcocystosis was suspected antemortem in 3 lorikeets (3-5 yr old); these birds died despite antiprotozoal therapy. The predominant lesion was pneumonia associated with S. falcatula-like schizonts in pulmonary vascular endothelium. The multilocus PCR-DNA sequencing ( 18S rDNA, 28S rDNA, ITS-1, and cox1) of frozen lung tissue confirmed S. falcatula infections in all 3 birds. Our results and previous studies suggest that acute pulmonary form of sarcocystosis is a major contributor of death to Old World psittacine birds.

This chapter reviews common diseases in perching birds in the orders Passeriformes, Caprimulgiformes, Coraciiformes, Piciformes, Bucerotiformes, and Apodiformes. Focus is on of the characteristic gross and histologic lesions they produce. Topics include iron overload, zinc toxicosis and wind turbine and window strike as well as infection with West Nile virus, poxvirus, Salmonella spp., and systemic isosporidiosis. Several diseases, including malaria, have significant population and conservation effects.

A 37-year-old, female Chilean flamingo (Phoenicopterus chilensis) presented with severe facial angioedema, bilateral corneal and palpebral edema, nictitating membrane paralysis, bradycardia, bradypnea, hypothermia, and numerous stingers and remnants of eastern yellow jacket wasps (Vespula maculifrons) attached to the feathers of the head, palpebrae, and conjunctiva. Evaluation of 2 complete blood cell counts and results of plasma chemical analysis and serum protein electrophoresis revealed severe increases in creatinine phosphokinase and aspartate aminotransferase activity, electrolyte disturbances, and moderate increases in levels of α1, α2, β1, and γ immunoglobulins when compared with reference interval values and conspecifics. Despite intensive treatment, the bird died 19 hours after presentation. Results of histologic evaluation of tissues were compatible with envenomation. Response to envenomation in avian species is not documented but should be considered in birds presenting with angioedema.

Infection with the fungal organism Batrachochytrium dendrobatidis was documented in two captive populations of aquatic caecilians (Typhlonectes natans), including 24 confiscated animals at the Bronx Zoo's Wildlife Health Center and two captive-born animals at the Phoenix Zoo. The animals at the Bronx Zoo were asymptomatic, and infection was discovered during quarantine polymerase chain reaction screening. Both animals at the Phoenix Zoo were clinically ill, and Batrachochytrium dendrobatidis infection was confirmed in both animals, but it is unclear what role, if any, the infection played in the animals' clinical signs. All of the Bronx Zoo's caecilians were successfully cleared of infection by elevating to and then holding water temperatures at 32.2 degrees C (90 degrees F) for 72 hr. One animal at the Phoenix Zoo died before treatment could be instituted, and the second died despite treatment with a 0.01% itraconazole bath. Chytridiomycosis has only been very recently first reported in caecilians, and much remains unknown about its behavior in this amphibian order. This is the first published report of Batrachochytrium dendrobatidis infection in captive-born caecilians and also the first describing details of treatment of chytridiomycosis in caecilians. It appears that raising tank temperature to 32.2 degrees C for 72 hr is a safe and effective treatment for aquatic caecilians with chytridiomycosis.

An 11-yr-old captive-born male Everglades ratsnake (Elaphe obsoleta rosalleni) presented with dysecdysis, hyperkeratosis, and inappetance. Two skin biopsies demonstrated a diffuse hyperkeratosis with both a bacterial and fungal epidermitis. Fusarium oxysporum was cultured from both biopsies and considered an opportunistic infection rather than a primary pathogen. Medical management was unsuccessful, and the snake was euthanized. Histologic findings included a pituitary cystadenoma arising from the pars intermedia, severe intestinal lipidosis, generalized epidermal hyperkeratosis, and lesions consistent with sepsis. It is hypothesized that endocrine derangements from the pituitary tumor may have caused the skin and intestinal lesions.

Four Roller pigeons (Columba livia f. dom.) at the Philadelphia Zoo died suddenly. Necropsy examination revealed macroscopic hepatitis. Microscopically, the predominant lesions were in liver, characterized with necrosis and mixed cell inflammatory response. Sarcocystis calchasi-like schizonts and free merozoites were identified in liver. Transmission electron microscopy confirmed that schizonts were in hepatocytes. A few schizonts were in spleen. PCR using S. calchasi-specific primers confirmed the diagnosis. Neither lesions nor protozoa were found in brain and muscles. This is the first report of acute visceral S. calchasi-associated sarcocystosis in naturally infected avian hosts.

Recent studies of serum iron and iron binding capacity have indicated that tapirs could be at risk of developing hemochromatosis. However, in recent surveys of pathologic findings in tapirs, hemochromatosis was not reported as a cause of death. This study reviews necropsy reports from three species of tapir (Baird's tapir [Tapirus bairdii], Malayan tapir [Tapirus indicus], and Brazilian tapir [Tapirus terrestris]) at the Philadelphia Zoological Garden between 1902 and 1994. Twelve cases of hemosiderosis, including fatal hemochromatosis in two Baird's tapirs, were found among 19 cases examined histologically. Hemochromatosis has previously been reported in the horse, rhinoceros, and in one Brazilian tapir. Dietary factors were investigated but could not be confirmed to have contributed to the incidence of hemosiderosis and hemochromatosis in the three species of tapir in the Philadelphia Zoological Garden collection.

Objective—To compare efficacy and safety of meso- 2,3-dimercaptosuccinic acid (DMSA) and Ca EDTA for treatment of experimentally induced lead toxicosis in cockatiels ( Nymphicus hollandicus).Animals—137 (69 females, 68 males) healthy cockatiels between 6 months and 8 years old.Procedure—Lead toxicosis was induced by placing lead shot in the gastrointestinal tract. Treatment with Ca EDTA (40 mg/kg of body weight, IM, q 12 h), DMSA (40 or 80 mg/kg, PO, q 12 h), and sodium sulfate salts (SSS; 0.5 mg/kg, PO, q 48 h) was initiated 4 days after induction of lead toxicosis. Blood lead concentrations were determined, using atomic absorption spectrophotometry. Number of birds surviving and blood lead concentrations were compared among groups.Results—In Phase II of the study, administration of DMSA and Ca EDTA significantly decreased blood lead concentrations when used alone or in combination in birds with lead toxicosis. Addition of SSS did not result in further decreases in lead concentrations. Eight of 12 (66.7%) birds without lead toxicosis given 80 mg of DMSA/kg did not survive to the end of the study . Lesions related to treatment with chelating agents were not detected during necropsy.Conclusions and Clinical Relevance—DMSA and Ca EDTA are effective chelating agents in cockatiels. Because DMSA is administered orally, it may be easier than other chelating agents for bird owners to administer at home. However, the narrow margin of safety of DMSA indicates that this agent should be used with caution. (Am J Vet Res2000;61:935–940)

An 8-yr-old intact male Grant's zebra (Equus burchelli bohmi) was referred to the Veterinary Medical Teaching Hospital of the University of California-Davis after being found in the owner's pasture obtunded and in lateral recumbency. The animal was hypothermic, weak, and unwilling to rise. There was no evidence of trauma, and the zebra had seemed normal the preceding evening. There was no extensor rigidity, and cranial nerve reflexes were normal. Flexor and extensor reflexes were weak upon initial examination. A complete blood count and serum biochemistry analysis revealed a mild leukocytosis, hyperfibrinogenemia, hypoglycemia, hyponatremia, hypochloremia, hypocalcemia, and hypoalbuminemia. Urinalysis was normal, and a urine toxicology screen for alkaloids was negative. No toxic substance was found in the hay or pasture grasses although the owner reported the presence of yellow star thistle and mushrooms in the pasture. The cerebrospinal fluid cytologic and biochemical analyses were normal, but antibodies to Sarcocystis neurona were detected. The zebra died despite aggressive supportive therapy over a 4-day period. The necropsy demonstrated severe gastrointestinal nematodiasis that could account for hypoalbuminemia and electrolyte abnormalities. Histopathologic examination of the nervous system revealed focal areas of perivascular cuffing in the brainstem that were comprised mainly of lymphocytes, monocytes, and plasma cells. Immunohistochemical staining identified the presence of S. neurona merozoites associated with the lesions. This zebra probably died from severe endoparasitism that resulted in malabsorption, weakness, and recumbency rather than from encephalitis associated with S. neurona merozoites. Equine protozoal myeloencephalitis has not been reported previously in nondomestic equids.

Eleven cases of congenital anomalies were identified in 210 (5%) juvenile northern elephant seals (Mirounga angustirostris) found stranded along the central California (USA) coast from 1 January 1988 to 31 December 1995. Seven individuals had mild-to-moderate hydrocephalus involving the lateral ventricles bilaterally, or the lateral and third ventricles. Two animals had severe cardiac anomalies: hypoplasia of the right ventricle with overriding aorta, and ventricular septal defect. Other anomalies included single cases of hydronephrosis, focal pulmonary dysplasia, and congenital epidermal angiomatosis. Common intercurrent disease processes were verminous pneumonia and arteritis, verminous enteritis and colitis, and splenic and hepatic hemosiderosis. The more severe anomalies were considered to be the cause of debilitation and stranding. Milder anomalies were found incidentally during routine gross necropsy and histopathologic examination.

Coccidioidomycosis is described in seven California sea lions (Zalophus californianus) admitted to The Marine Mammal Center, Sausalito, California (USA), between January 1986 and December 1994. Diagnoses were confirmed by histology in all seven cases, culture in three cases, and serology in one case. These are believed to be the first published cases of coccidioidomycosis in free-ranging California sea lions.

A 12-year-old male burrowing owl (Athene cunicularia) was presented for evaluation of a mass in the right cervical region. A thymoma was diagnosed after surgical resection and histopathologic evaluation. Extensive adherence of the thymoma to the esophagus and suspected invasion into the right jugular vein contributed to a poor postsurgical outcome. Diagnosis and treatment of thymomas in avian species is similar to that in mammals. Surgical removal of noninvasive thymomas is usually curative. Thymomas are rarely reported in avian species and this is the first report in a strigiform bird.

From May 2007 to June 2008, 30 of 49 Wyoming toads (Bufo baxteri) kept at Omaha's Henry Doorly Zoo (Nebraska, USA) died showing clinical signs of ventral erythema, inappetance, lethargy, and delayed righting reflex. Treatment with antifungals and antibiotics was unsuccessful in all cases. Histopathologic analyses revealed dermatitis as the primary problem in 20 of 21 toads in which skin was examined. Fungal dermatitis was present in 17 toads, with hyphae approximately 1-3 mm in diameter, and parallel cell walls and frequent septations. In 14 animals, the fungal dermatitis was the main pathologic lesion. Several species of bacteria were associated with all cases. A few animals tested positive for Ranavirus using polymerase chain reaction. Fusarium sp. was consistently cultured from skin, feces, kidneys, and from powdered food provided to crickets. Four isolates were identified as Fusarium proliferatum, Fusarium oxysporum, Fusarium solani, and Fusarium verticillioides, which suggested a secondary role of fungi. A specific underlying cause of disease could not be found, although the roles of humidity and Ranavirus infection are discussed, along with the well-known susceptibility of bufonids to fungal dermatitis.

A group of 202 tiger salamanders (Ambystoma tigrinum) was brought into captivity due to habitat destruction. Half of these animals died, over two mo, showing generalized hemorrhages compatible with an infectious disease, but an etiologic agent was not determined. Encysted metacercarial stages of trematodes within the skeletal musculature, coelomic cavity, and subcutaneous space were additional necropsy findings. One salamander had scoliosis and multiple skin nodules. A radiograph showed no skeletal abnormality to explain the scoliosis; however, numerous round nodules were more radiodense than the surrounding tissue. A presumptive diagnosis of generalized trematodiasis was made, yet the salamander did not improve after a course of praziquantel and subsequently died. Necropsy revealed massive, encysted trematode infection. Histologic examination revealed marked multifocal intramuscular, subcutaneous, and coelomic trematodiasis with associated necrosis and inflammation. Based on gross morphology, the trematode was identified as a member of the genus Clinostomum.

Intestinal lymphoma of granular lymphocytes was diagnosed in a 6-year-old fisher (Martes pennanti) and a geriatric Eurasian otter (Lutra lutra). Clinical signs included lethargy and inappetance in both animals and vomiting and occasional diarrhea in the fisher. The diagnosis in both cases was made using cytology of fresh tissue, histology of fixed tissues, and immunohistochemistry. Granules were seen most clearly on cytologic examination of direct impressions from fresh tissue. Because granules were absent in most histologic sections, cytology of fresh tissue was essential for the diagnosis. Immunohistochemistry determined that the neoplastic cells had positive membranous immunoreactivity to CD3 and were negative for CD79a, which was consistent with alimentary T-cell lymphoma. The disease course in both animals was presumed to be aggressive, with rapid progression of clinical signs, high mitotic index and effacement of local intestinal architecture in both cases, and metastatic disease in the fisher. To the authors' knowledge, this is the first report of lymphoma of granular lymphocytes in a fisher and a Eurasian otter.

A neonatal male sable antelope (Hippotragus niger) was found dead. A 5 by 12-cm lobulated mass was present in the oral cavity, attached to the caudal border of the soft palate; this mass contained hair, cartilage, bone, nervous tissue, muscle, and multiple gland-like structures. Histopathologic diagnosis was consistent with oropharyngeal teratoma. As a result of the lack of wear of the fetal hooves, the firm, collapsed appearance of the lungs, and the lack of other gross or histopathologic abnormalities, the oropharyngeal tumor is suspected to have caused an airway obstruction, resulting in the calf's early postnatal death. This is the first report of an oropharyngeal teratoma in the veterinary literature.

A retrospective study of neoplasia in reptiles held at the Philadelphia Zoological Garden was conducted. A total of 3,684 original necropsy reports for the period 1901-2002 were reviewed and revealed 86 cases of neoplasia. Original glass slides or re-cuts from paraffin-embedded tissue blocks were examined for confirmation of the original diagnosis. At necropsy, a total of six neoplasms were identified in six of 490 chelonians (1.2%), 22 neoplasms in 19 of 736 lizards (3.0%), and 58 neoplasms in 53 of 1,835 snakes (2.9%). An additional 12 neoplasms were found in biopsies of one turtle and 10 snakes. In the chelonians, all the neoplasms were seen in turtles, four of six tumors were malignant (66%) and no organ predilection was noted. For lizards, the liver was the most commonly affected organ, with 7 of 22 primary neoplasms (31%). Multiple tumor types were identified in three lizards (15%), metastasis occurred in five cases (25%), and malignant tumors were identified in 16 cases (73%). In snakes, the liver was most frequently affected by neoplasia at necropsy, with 13 of 58 primary neoplasms (22%); multiple types of neoplasm were identified in five cases (10%) and metastasis in six (9%); and 42 tumors (80%) were diagnosed as malignant. When biopsies were included for snakes, however, the skin was the most commonly affected organ, with 17 of 69 neoplasms (24%). One of five lizards (20%) and four of six snakes (66%) with metastasis also had a second primary neoplasm. Since 1967, the incidence of lizard neoplasia has increased from 0.7% to 5.9%, and snake neoplasia has increased from 2.6% to 9.3%.