Morbidity and Mortality in a Large Group of Amphibians Confiscated from the Pet Trade
Fifty-three species of amphibians were confiscated from an animal dealer that supplies national pet store chains. A total of 696 live individuals were transported to the Detroit Zoological Society and housed in quarantine facilities. At least 85% of the animals were presumed to be wild-caught based on the documented location of packing. On arrival, many animals had symptoms of illness and early mortality rates were high. In this retrospective review, causes of morbidity and mortality were determined by reviewing diagnostic testing results and necropsy findings for the period 12 months after arrival.
Frozen postmortem specimens were submitted for PCR testing for Ranavirus from species with any consistent histopathology findings including skin ulceration; inclusion bodies; or necrosis and/or hemorrhage in liver, kidney, hematopoietic tissue, or gastrointestinal tract. Samples submitted were either entire carcass or liver, kidney, and skin. TaqMan PCR testing for chytridiomycosis was performed antemortem using skin swab sampling.
The overall mortality rate during the first year was 55%; 275 of 494 anurans and 92 of 168 caudates died. Infectious causes of illness were prevalent and included Ranavirus, chytridiomycosis, chromomycosis, and parasitism. In some cases, death was caused by aberrant tissue migration of spirurid nematodes, while in others parasite load was deemed high enough to cause mortality. Many animals lacked a specific etiology but showed signs of chronic disease and immunocompromise.
The authors would like to thank Dr. Dana Tatman-Lilly for assistance with data entry and Drs. Ryan Colburn and Karla Fenton for assistance with necropsies.