Meeting Abstract

P3.121  Wednesday, Jan. 6  Yolk and albumin corticosterone concentrations in eggs laid by white versus brown laying hens NAVARA, KJ*; PINSON, SE; Univ. of Georgia; Univ. of Georgia knavara@uga.edu

Animals respond to stressful conditions with variable intensity. When stress is imposed on laying females, permanent trans-generational effects can also occur through the transmission of corticosterone (CORT), the primary avian stress hormone, to offspring through the egg. So, when examining the effects of stress on laying females, it is also important to determine how that stress impacts offspring as well. Previous studies have shown that white leghorn hens show a heightened response to stress compared to Hyline brown hens, producing significantly more corticosterone and displaying longer bouts of tonic immobility after handling, while baseline levels of CORT are similar between the strains. We tested the hypothesis that higher stress responsiveness would correspond to chronic accumulation and thus higher concentrations of CORT in egg yolks following exposure to stressors associated with routine maintenance. Eggs were collected from white and brown hens that were undisturbed except for daily feeding and routine egg collections. CORT was quantified in plasma, egg yolks, and albumin and compared between strains. We predicted that CORT concentrations in yolk would be higher in eggs from white versus brown hens, but that short-term measures including plasma and albumin CORT would not differ between strains. As predicted, yolk CORT concentrations were significantly higher in eggs produced by white hens, nearly twice those found in eggs laid by brown hens. Plasma and albumin concentrations of CORT were similar between groups. These results suggest that offspring hatching from eggs laid by white leghorn hens are exposed to significantly more stress hormones through concentration in the egg yolk, which could permanently imprint offspring physiology and behavior.