Body, Abdominal Fat, and Testes Weights, and Line by Sex Interactions in Japanese Quail Divergently Selected for Plasma Cholesterol Response to Adrenocorticotropin ,

Abstract

Line by sex interactions of BW, abdominal fat, testes weight, and plasma cholesterol were investigated in two Japanese quail lines. High (H-PCHOL) and low (L-PCHOL) quail lines had been developed by 18 generations of divergent selection for plasma cholesterol response to adrenocorticotropin (ACTH). Quail were from Generation 28 breeders maintained under a normal environment with no exposure to exogenous ACTH after Generation 18. Quail from growth-selected lines were also used to examine relationships between BW and plasma cholesterol.Body weights of H-PCHOL quail were significantly (P≤.05) heavier than BW of L-PCHOL quail at 2 and 4 wk of age. However, at 8, 16, and 28 wk BW were similar. Quail from long-term, growth-selected lines were observed to have plasma cholesterol levels similar to those of control lines. Therefore, early BW changes in H-PCHOL and L-PCHOL lines may not be related to plasma cholesterol changes. At 2 and 4 wk, male and female plasma cholesterol values were similar in the H-PCHOL and L-PCHOL lines, however, at 8 and 16 wk males had higher values than females in the H-PCHOL line, and females had higher values than males in the L-PCHOL line. Because interactions were present only after sexual maturity was reached, sex hormones may be involved in the expression of these interactions. Quail in the L-PCHOL line were observed to have significantly (P≤.05) more abdominal fat and significantly (P≤.05) smaller testes than quail in the H-PCHOL line.