Meeting Abstract

19.2  Tuesday, Jan. 4  The contribution of anti-parasite behavior to resistance and tolerance of trematode infections in anuran tadpoles SEARS, B.F.*; ROHR, J.R.; MARTIN, L.B.; University of South Florida; University of South Florida; University of South Florida bsears@mail.usf.edu

Hosts can cope with parasites utilizing two strategies: resistance, which reduces the intensity of an infection, and/or tolerance, which mitigates the deleterious effects of an infection. Resistance can be achieved through both immune defenses as well as anti-parasite behavior, which may include specific behaviors by the host when contacted by a parasite. Larval amphibians are susceptible to trematodes and can employ anti-parasite behaviors that have been shown to reduce the probability of infection. Here, we compare anti-parasite behavior across a diverse group of anurans (Osteopilus septentrionalis, Hyla femoralis, Hyla gratiosa, Pseudacris sp., and Gastrophryne carolinensis) that differ considerably in life-history traits, particularly in rate of development. We exposed both benzocaine-anesthetized and control tadpoles to 0, 10, 15, 20, or 30 cercariae and quantified the resulting infection intensities (indicators of resistance) and mass change and mortality (indicators of tolerance), in the 7 days post-exposure to determine how behavioral resistance affects variation in infections among species. Anesthesia significantly reduced growth in Pseudacris sp., and parasite exposure significantly reduced growth in O. septentrionalis, H. femoralis, and G. carolinensis, with tadpoles exposed to more parasites gaining significantly less weight over the course of 7 days. Ongoing analyses are evaluating how life history traits impact variation in resistance and tolerance as well as the physiological mediators thereof.