Impacts of Temperature on Immune Performance in a Desert Anuran (anaxyrus Punctatus)

Desert species, especially ectotherms, experience temperature-related challenges throughout their lives. Temperature affects many aspects of ectotherm physiology, including immune function. The goal of this study was to investigate how temperature affects the immune system of a common desert toad, Anaxyrus punctatus. We used three well-known eco-immunological techniques (bacterial lysis, hemagglutination and phytohaemagglutinin assays) to measure aspects of immune performance across temperature. Field and preferred temperatures were used to determine the temperatures utilized in the immunological assays. We found that temperature affects bactericidal and hemagglutination capacity in this species, but not inflammatory response. We also found that bactericidal and hemagglutination capacity are optimal at extremely high temperatures compared to the preferred temperature of this species or extremely low temperatures. These results have implications for disease management in desert amphibians as well as the vulnerability of this species to emerging infectious diseases.