Meeting Abstract
Immune system activation in animals is energetically costly and may reduce reproductive investment. In ectothermic vertebrates, immune activation presents an interesting trade-off in energy investment between thermoregulation and reproduction. During an infection, some ectotherms employ thermoregulatory behaviors which increase body temperature and aid the immune system. Other sickness behaviors include decreased activity levels and anorexia. While effective, these strategies may come at the expense of other behaviors (e.g., anti-predation behaviors and reproduction). Reproduction of the red-sided garter snake, Thamnophis sirtalis parietalis, has been particularly well-studied, and this species has been noted to prioritize reproductive behaviors over thermoregulation. However, few studies have investigated sickness behaviors and immune-mediated thermoregulation in red-sided garter snakes. In this study, we investigated thermoregulatory behaviors and activity levels of garter snakes in response to an immune challenge. Specifically, we injected male and female snakes with lipopolysaccharide (LPS) or saline. Snakes were placed into a thermal gradient and their thermal preference and activity levels were scored. Overall, LPS treatment resulted in a decrease in activity levels, but the effect was only significant for male snakes. Our results provide evidence of behavioral costs of immune activation in garter snakes, which may contribute to conflict between reproduction and the immune system.
