Pesticide exposure during development increases mortality to infections in adulthood


Meeting Abstract

P2.35  Wednesday, Jan. 5  Pesticide exposure during development increases mortality to infections in adulthood ROHR, JR; HALSTEAD, NT; JOHNSON, SA; RAFFEL, TR; MCMAHON, T; MARTIN, LB*; University of South Florida, Integrative Biology; University of South Florida, Integrative Biology; University of Florida, IFAS Plant City; University of South Florida, Integrative Biology; University of South Florida, Integrative Biology; University of South Florida, Integrative Biology lmartin@cas.usf.edu

Early-life exposure to stressors, such as pesticides, can alter disease risk and survival of humans and domesticated animals later in life. However, these associations have not been considered in wild organisms, particularly amphibians, a taxon experiencing global declines associated with the disease chytridiomycosis. We hypothesized that exposure of tadpoles to atrazine, the second most commonly used herbicide in the U.S., early in life would increase mortality risk from the chytrid fungus (Batrachochytrium dendrobatidis; Bd) later in life, as atrazine impacts both immune functions and infections outcomes in amphibians. We exposed Cuban tree frog (Osteopilus septentrionalis) tadpoles to the expected environmental concentration of atrazine (102 µg/L) or to control (acetone) for one week, either early (Gosner stage 26-28) or late (stage 35-37) in development. To test for long-term effects of atrazine on response to Bd, animals were exposed to Bd either immediately after atrazine exposure (tadpoles) or approximately seven weeks later (recently post-metamorphosis), and survival was compared with controls. Atrazine exposure during the first development window did not affect mortality. However, atrazine exposure during the second developmental window caused increased Bd-induced mortality relative to controls. Moreover, the magnitude of this effect was similar regardless of whether exposure to Bd occurred immediately after the atrazine exposure or seven weeks later. Hence, early-life exposure to atrazine had enduring impacts on mortality risk from Bd in Cuban tree frog tadpoles but this effect was greater during later development.

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