Meeting Abstract
Studies suggest that, in animals, personality type is correlated with the degree of stress responsiveness. For example, white laying hens are reactive, flighty, and exhibit large hormonal and behavioral responses to stress while brown laying hens are proactive, exploratory, and exhibit low hormonal and behavioral responses to stress. However, whether these “personalities” are also correlated with other physiological differences is unknown. The objective of this study was to determine if animals with different personality types also exhibit differences in immunity. We hypothesized that white hens, with reactive personalities, would show more dampened immune responses than brown hens due to their exposure to higher levels of corticosterone throughout life. To assess immune function in white and brown hens, we compared febrile responses to an injection of lipopolysaccharide (LPS) or saline, the inflammatory response to a PHA injection in the toe web, and innate phagocytic activity in whole blood collected from both strains. Contrary to our predictions, white hens had significantly greater swelling of the toe web in response to PHA injection than brown (p=0.018). There was no effect of treatment on the febrile response to LPS or saline injection. However, white hens showed a significantly greater reduction in egg production after LPS injection than brown hens and also had significantly greater plasma CORT levels after exposure to LPS than brown hens did, suggesting a larger sickness response overall.
