Selection for High Egg Testosterone and Immune Response of Young Japanese Quail under Mild Food Restriction

Abstract

Maternal androgens link the mother and her progeny and can shape postnatal growth and development. However, the positive effects of prenatal androgens are likely to be balanced by negative impacts on other fitness related traits, such as immune defence, especially when animals are subjected to unfavourable environmental conditions (e.g. a food shortage). To examine these relationships, we investigated the effects of genetic selection on high (HET) and low (LET) egg testosterone content in Japanese quail on the immune system under mild food restriction. To test immune response, we examined: (1) skin swelling after subcutaneous phytohaemagglutinine injection; and (2) acute phase response in reaction to intraperitoneal lipopolysaccharide (LPS) administration. Food restriction decreased body mass in comparison with ad libitum fed animals, but food restriction did not diminish the positive influence of increased maternal testosterone (mT) on body growth. Furthermore, three hours after LPS injection, plasma corticosterone levels and heterophil/lymphocyte ratio were not affected by increased mT. In fact, cell mediated immunity was enhanced in the HET as compared to the LET line. Thus, our data indicate no trade-off between growth rate and immune response in young quail hatched from eggs with high mT, even under conditions of mild food deficiency.