Testicular response of non-breeding pheasants to human chorionic gonadotropin, chicken pituitary extract, and photoperiod.

This investigation was designed to compare the testicular response of non-breeding pheasants to human chorionic gonadotropin (HCG), chicken pituitary extract (CPE), and extended photoperiod exposure (20L:4D) by analyzing testicular weights, testicular histology, and plasma testosterone levels. Exposure to 20L:4D increased testicular weights and plasma testosterone levels significantly (P less than .01) and recovered spermatogenesis completely. Injections of CPE increased testicular weights (P less than .01) and recovered spermatogenesis partially, but had no significant effect on plasma testosterone levels. Effects of HCG were non-significant. It is suggested that either doses of HCG and CPE used in this study were not enough or non-breeding pheasants require pheasant gonadotropins for the complete recovery of testicular function.