The hormone-induced spawning of silver perch, Bidyanus bidyanus (Mitchell) (Teraponidae)

Abstract

Adult silver perch, Bidyanus bidyanus, were induced to spawn by the injection of human chorionic gonadotrophin (HCG) or a preparation of the pituitary gland from common carp (CPG). Males, injected with 200 IU/kg HCG, were placed with injected females in 2000-l concrete tanks, and spawning occurred 31–40 h after injection at a water temperature of 25°C. All females injected with 200 IU/kg HCG spawned completely, and the mean hatch rate of eggs was 88.8%. Higher dosages of HCG, and the use of CPG, resulted in reduced spawning success and, in general, lower mean hatch rates. Techniques for egg incubation are briefly described.