Clinical pathology of Bsal chytridiomycosis: hematological, biochemical, and serum protein analyses of infected Taricha granulosa
Grzelak, A., R. Kumar, C. Cray, E. D. Carter, P. Watcharaanantapong, K. Ash, B. A. Bajo, M. Bohanon, A. C. Peterson, M. J. Gray, and D. L. Miller.  2020.  9th World Congress of Herpetology, Otago, Dunedin, New Zealand.  (invited)

Abstract:
Batrachochytrium salamandrivorans (Bsal) is a recently discovered pathogen that is of global concern because of its potential to cause high mortality in amphibians, especially salamander species. Although little has been reported on the pathophysiological effects of Bsal, studies have made headway in understanding the pathogenesis of B. dendrobatidis (Bd), a similar fungus that has led to global amphibian population declines throughout the world. Studies found that electrolyte losses occur in amphibians infected with Bd from loss of osmoregulation through extensive skin pathology, and it is hypothesized that changes in electrolyte concentrations lead to paralysis and cardiac arrest. In our study, we hypothesize that species susceptible to Bsal chytridiomycosis would have similar losses in electrolytes, because like Bd, Bsal damages the epidermis and may affect skin osmoregulation. To test this hypothesis, we collected blood from the hearts of a larger susceptible species, Taricha granulosa, at necropsy using heparinized capillary tubes. A blood smear was prepared, and a portion of whole blood was added to Natt Herrick’s solution for total blood cell counts. The remaining blood was centrifuged and plasma was collected for blood chemistry profiles and protein electrophoresis. Initial biochemical results revealed decreases in sodium, chloride, and potassium in clinically affected individuals (5x106 dose). Moreover, protein electrophoresis revealed changes in protein concentrations that suggest the presence of inflammation and antibody production. By understanding the pathogenesis of Bsal, we aim to gain insight in developing treatment options and opportunities to mitigate and prevent spread of disease.