Meeting Abstract
We measured changes in standard metabolic rates (SMR) in response to different immune challenges and feeding treatments in the side-blotched lizard (Uta stansburiana). In the first experiment, lizards were randomly assigned to treatments of lipopolysaccharide (LPS) injection, cutaneous biopsy, both, or none (control). Two and three days after biopsies were administered, lizards were placed into closed-system respirometry chambers and their SMR were measured. There was a significant downregulation in SMR and a significant reduction in body mass in response to healing a cutaneous wound. Additionally, lizards that healed greater percentages of their wounds lost more weight. In the second experiment, lizards were randomly assigned to an ad libitum or restricted diet, and all were wounded. Again, we observed a downregulation in metabolic rate in response to a wound, and this decrease was positively correlated with healing rate. We also observed, as was expected, that standard metabolic rate was correlated with food intake, but food intake was not related to the decrease in metabolic rate following biopsy. These experiments yield new insight to the costs of immunity and how energy is allocated when animals are faced with different immune challenges in different energetic states.
