ANDROGEN REGULATION OF AVIAN PREMIGRATORY HYPERPHAGIA AND FATTENING -FROM ECO-PHYSIOLOGY TO NEUROENDOCRINOLOGY

In many high latitude-breeding avian species, reproductive and winteri ng seasons are separated by migratory periods that involve dramatic ph ysiological and behavioral adjustments such as hyperphagia and fat dep osition. The endocrine mechanisms responsible for these adjustments ha ve been extensively studied, yet remain only partly understood. The cu rrently available information indicates that food consumption and/or f attening can be experimentally modulated by multiple hormones includin g testosterone, prolactin, glucocorticoids, and opioids. These hormone s may control migratory functions through mutual interactions rather t han independently. Little is known, however, concerning the nature of these interactions and their relative importance in the control of ann ual cycles in natural conditions. This paper focuses on the role of go nadal androgens in the control of migratory functions, and it summariz es the information which is available on the physiological and behavio ral interactions between these androgens and other hormones.