Collection-Wide Amphibian Screening for Batrachochytrium Dendrobatidis at Five Zoological Parks
American Association of Zoo Veterinarians Conference 2009
Carlos E. Rodriguez1, DVM, DACVP; Allan P. Pessier2, DVM, DACVP; Timothy A. Georoff3, VMD; Denise McAloose1, VMD, DACVP; Jennifer Pramuk4, PhD
1Global Health Programs, Pathology and Disease Investigation, Wildlife Conservation Society, Bronx, NY, USA; 2Wildlife Disease Laboratories, San Diego’s Institute for Conservation Research, San Diego, CA, USA; 3Global Health Programs, Department of Clinical Care, Wildlife Conservation Society, Bronx, NY, USA; 4Department of Herpetology, Wildlife Conservation Society, Bronx, NY, USA
A fatal outbreak of amphibian chytridiomycosis in a group of critically endangered Kihansi spray toads (Nectophrynoides asperginis) prompted institution-wide testing for Batrachochytrium dendrobatidis (Bd) infection in the amphibian collections of the Wildlife Conservation Society (WCS). Animal sampling was accomplished following established protocols.1,2 A total of 363 samples from 45 amphibian species at the WCS’ four zoological parks and one aquarium were collected and tested over a period of 5 months. Quantitative real-time TaqMan PCR (qPCR) for Bd was performed by the Molecular Disease Laboratories at San Diego’s Institute for Conservation Research. Several individuals belonging to 7 of the species tested (dyeing arrow frog [Dendrobates tinctorius]; green and black poison arrow frog [Dendrobates auratus]; splashback poison arrow frog [Dendrobates galactonotus]; red-eyed tree frog [Agalychnis callidryas]; grey tree frog [Hyla versicolor]; wood frog [Rana sylvatica]; tiger salamander [Ambystoma tigrinum]; and aquatic caecilians [Typhlonectes natans]) were positive for Bd qPCR. None of the test-positive animals showed any evidence of clinical disease. All PCR-positive animals were treated prophylactically and subsequently re-tested. The results of this survey highlight the value of collection-wide amphibian Bd surveillance in identifying clinically unaffected animals and the importance of disease screening as part of routine quarantine protocols to prevent introduction of this disease into established animal collections.
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