Hormonal Control of Reproductive Behavior in the Avian Male

INTRODUCTION Behavioral components of reproduction are modulated, in great part, by gonadal hormones. Environmental factors such as photoperiod, social interactions, density, and housing exert effects on reproductive performance, and there is some evidence for altered behavior in response to these factors. The specific mechanism of action of hormones in the induction and modulation of reproductive behavior has received extensive research over the past few years; much of the evidence points to specific behavioral areas in the brain in which the hormones stimulate the various segments of reproductive behavior. Reproductive efficiency becomes critically important in domestic species for maintenance of the species as well as for providing animals or animal products for consumption. In the case of the domestic chicken, the Leghorn chicken has been selected for reproductive efficiency in production of eggs, whereas the White Rock chicken has been selected for rapid growth. Unfortunately, there has been a coincident decline …