Meeting Abstract
Emerging fungal pathogens have been proposed to be the greatest threat to biodiversity over other parasitic groups. Batrachochytrium dendrobatidis is an infectious fungal pathogen of the chytridiomycete class which has been found to be a contributing factor to hundreds of amphibian species extinctions worldwide. Because amphibians have illustrated an ability to acquire resistance to Bd, inducing resistance via treatment with flash-frozen, dead Bd may be the key to protecting susceptible populations. To determine the dose and duration of exposure necessary to induce resistance, we manipulated the duration and dose of exposure of adult frogs to dead Bd using a 5×5 response surface experimental design in the laboratory that includes the full vertical and horizontal dose and duration gradients and the four corners of the treatment matrix so that we test 13 of the 25 possible treatments. We exposed Cuban tree frogs (Osteopilus septentrionalis) to 5 levels of dead Bd, as well as a control, every other day for 1, 2, 3, or 4 weeks. After the exposures, we exposed all frogs to live Bd (1ml of 1×106 zoospores/ml) and maintained them at 18°C for two weeks in an environmental chamber. Frogs were swabbed and Bd burdens quantified by estimating the density of zoospores using a StepOne Real-Time PCR System. We hypothesize assessment of infection intensity by dose and duration will provide this missing information needed for conservation efforts.
