Amphibian resistance to chytridiomycosis increases following low virulence chytrid fungal infection or drug-mediated clearance

Amphibian biodiversity is experiencing ongoing declines due in part to the infectious disease, chytridiomycosis. Efforts to mitigate the effects of the causal agent of chytridiomycosis, Batrachochytrium dendrobatidis (Bd), in the wild have not been wholly effective. Translocations are an important management tool for amphibians, and immunizations represent a possible strategy for preparing amphibians for release across a landscape where Bd exists. We evaluated the utility of using an isolate of Bd that was shown to be hypovirulent to the relict leopard frog (Rana onca) as a transmissible inoculum for promoting chytridiomycosis-resistance. We conducted a cohousing experiment to determine if the isolate we used could be passed between R. onca without increasing in virulence. We then  followed with an experiment where frogs that were exposed to the hypovirulent isolate were then challenged with a virulent Bd isolate. In other experiments, we evaluated whether Bd infections followed by clea...