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West Nile virus (genus Flavivirus) outbreaks and mortality events have been documented in both wild and captive avian species, including penguins. Serologic response to vaccination in avian species has varied and appears to be largely species dependent; however, Humboldt penguins ( Spheniscus humboldti ) previously showed excellent rates of seroconversion. The goal of this study was to determine virus neutralization titers of 17 Humboldt penguin hens and their subsequent eggs, chicks, or both following vaccination with a killed West Nile vaccine. Chicks were also vaccinated at 56, 70, and 84 days old. Titers were measured from 10-346 days prior to lay as well as serially in seven chicks. Data collected showed positive rank correlation between maternal titers and yolk titers (ρ = 0.90, P0.0001, n = 14) but no association between booster vaccination and yolk titers. All seven chicks had detectable antibody on days 14 and 28, and antibody levels had increased (relative to day 56) in 3 of 6 chicks (50%; 95% confidence interval 14-86%) by day 112. Further information is provided on a suggested vaccination schedule for Humboldt penguin chicks based on a time-dependent decline in maternal antibody titers. Cell-mediated immunity and experimental challenge following vaccination have not yet been investigated in this species.

Aspergillosis is a common respiratory fungal disease in penguins managed under human care. Triazole antifungal drugs, including itraconazole, are most commonly used for treatment; however, itraconazole treatment failures from drug resistance are becoming more common, requiring newer treatment options. Voriconazole, a newer triazole, is being used more often. Until recently, no voriconazole pharmacokinetic studies had been performed in penguins, leading to empiric dosing based on other avian studies. This has led to increased anecdotal reporting of apparent voriconazole toxicity in penguins. This report describes 18 probable and 6 suspected cases of voriconazole toxicity in six penguin species from nine institutions: 12 African penguins (Spheniscus demersus), 5 Humboldt penguins (Spheniscus humboldti), 3 Magellanic penguins (Spheniscus magellanicus), 2 gentoo penguins (Pygoscelis papua papua), 1 macaroni penguin (Eudyptes chrysolophus), and 1 emperor penguin (Aptenodytes forsteri). Observed clinical signs of toxicity included anorexia, lethargy, weakness, ataxia, paresis, apparent vision changes, seizure-like activity, and generalized seizures. Similar signs of toxicity have also been reported in humans, in whom voriconazole therapeutic plasma concentration for Aspergillus spp. infections is 2-6 μg/ml. Plasma voriconazole concentrations were measured in 18 samples from penguins showing clinical signs suggestive of voriconazole toxicity. The concentrations ranged from 8.12 to 64.17 μg/ml, with penguins having plasma concentrations above 30 μg/ml exhibiting moderate to severe neurologic signs, including ataxia, paresis, and seizures. These concentrations were well above those known to result in central nervous system toxicity, including encephalopathy, in humans. This case series highlights the importance of species-specific dosing of voriconazole in penguins and plasma therapeutic drug monitoring. Further investigation, including pharmacokinetic studies, is warranted. The authors recommend caution in determining voriconazole dosages for use in penguin species.

Red pandas (Ailurus fulgens) are susceptible to canine distemper, with a number of reported vaccine-induced canine distemper cases. Canarypox-vectored recombinant canine distemper vaccines (PureVax Ferret Distemper [PFD] and Recombitek CDV [rCDV]) provide protection without inoculating a live distemper virus, but there are currently no published data regarding these vaccines' safety and efficacy in red pandas. One hundred twenty-two serum samples were collected from 50 captive red pandas and analyzed for antibodies to canine distemper. All naive red pandas (n = 20) had negative titers. Naive pandas receiving two PFD vaccinations had either negative or intermediate titers (n = 4). In contrast, naive pandas receiving a series of two or three rCDV vaccinations (n = 14) had greater antibody responses. Red pandas vaccinated with PFD >12 mo since their last vaccination and a rCDV booster vaccination showed the highest titers observed. We recommend red pandas be administered a series of at least three recombinant vaccine (PDF or rDCV) vaccinations, followed by annual booster vaccinations.

Eight free-ranging timber rattlesnakes (Crotalus horridus) from two geographically isolated Massachusetts populations were observed with skin lesions located primarily on the head but occasionally also on the lateral and ventral surfaces of the body. The snakes underwent health assessments that included physical examination, clinical pathology, full body radiographs, and full thickness biopsies of skin lesions. Each snake had fungal elements present histologically in tissue sections from skin lesions. Ophidiomyces ophiodiicola was identified from skin lesions using polymerase chain reaction in all eight snakes.

All anuran specimens in the Wildlife Conservation Society's collections testing positive for Batrachochytrium dendrobatidis (Bd) were treated with itraconazole and then studied after treatment to assess the long-term effects of itraconazole and the drug's effectiveness in eliminating Bd carriers. Twenty-four individuals and eight colonies of 11 different species (75 total specimens) tested positive for Bd via polymerase chain reaction (PCR) on multicollection survey. All positive individuals and colonies were treated with a 0.01% itraconazole bath solution and retested for Bd via one of two PCR methodologies within 14 days of treatment completion, and all were negative for Bd. A total of 64 animals received secondary follow-up PCR testing at the time of death, 6-8 mo, or 12-15 mo post-treatment. Fourteen animals (14/64, 21.9%) were PCR positive for Bd on second follow-up. The highest percentage positive at second recheck were green-and-black poison dart frogs (Dendrobates auratus; 5/5 specimens, 100%), followed by red-eyed tree frogs (Agalychnis callidryas; 4/11, 36.4%), grey tree frogs (Hyla versicolor; 1/3, 33.3%), and green tree frogs (Hyla cinera; 3/11, 27.3%). Re-testing by PCR performed on 26/28 individuals that died during the study indicated 11/26 (42.3%) were positive (all via DNA extracted from formalin-fixed paraffin-embedded skin sections). However, there was no histologic evidence of chytridiomycosis in any of 27/28 individuals. The small number of deceased animals and effects of postmortem autolysis limited the ability to determine statistical trends in the pathology data, but none of the necropsied specimens showed evidence of itraconazole toxicity. Problems with itraconazole may be species dependent, and this report expands the list of species that can tolerate treatment. Although itraconazole is effective for clearance of most individuals infected with Bd, results of the study suggest that repeat itraconazole treatment and follow-up diagnostics may be required to ensure that subclinical infections are eliminated in amphibian collections.

Laboratory records of serology results from captive macropodidae sampled between 1997 and 2005 were reviewed to assess the seroprevalence of retrovirus exposure. Serum samples from 269 individuals (136 males, 133 females) representing 10 species of macropods housed in 31 North American captive collections were analyzed for retrovirus antibody using an indirect immunofluorescent assay. The prevalence of positive antibody titers comparing male versus female, between species, between age groups, and among animals with identified parentage was examined by nonparametric statistical analyses. Median age of animals at time of sample collection was 36 mo (range 2-201 mo). Total percentage seropositive was 20.4%. Serum antibody was detected in 31 of 47 (66.0%) tammar wallaby (Macropus eugenii), nine of 24 (37.5%) yellow-footed rock wallaby (Petrogale xanthopus), four of 11 (36.4%) swamp wallaby (Wallabia bicolor), 10 of 80 (12.5%) red-necked wallaby (Macropus rufogriseus), and one of 54 (1.9%) parma wallaby (Macropus parma). No individuals of western gray kangaroo (n=3) (Macropus fuliginosus), eastern gray kangaroo (n=19) (Macropus giganteus), common wallaroo (n=6) (Macropus robustus), red kangaroo (n=11) (Macropus rufus), or Matschie's tree kangaroo (n=14) (Dendrolagus matschiei) were positive for retrovirus antibody. These results demonstrate that five species of captive macropods have a history of exposure to retrovirus, with the highest percentage seropositive and highest statistical correlation in M. eugenii (pair-wise Fisher's exact test, alpha = 0.05). Additionally, one wild-caught M. eugenii was confirmed seropositive during quarantine period, indicating that retrovirus exposure may exist in wild populations.

A 13-year-old male green tree monitor (Varanus prasinus) presented with lethargy and chronic weight loss. Complete blood count (CBC) revealed marked leukocytosis (total leukocyte count = 278.1 × 103/μl) and peripheral blood films were characterized by marked lymphocytosis comprised of small, well-differentiated lymphocytes. Bone marrow aspiration revealed increased cellularity with a predominance of well-differentiated lymphocytes. Using immunocytochemistry, neoplastic lymphocytes in peripheral blood films were positive for CD3 epsilon and negative for CD79a and BLA.36, consistent with T-cell chronic lymphocytic leukemia (CLL). Distal tail necrosis was noted 17 days post-presentation and treated with partial caudectomy. Treatment was initiated for CLL with 0.8 mg/kg prednisone q 48 h 22 days post-presentation. CBC on days 94 to 151 post-presentation showed marked reduction in leukocytosis (counts remaining below 40.0 × 103/μL). The animal displayed improvement in activity, appetite, and gained we...