Effect of pituitary gland from spent and unspent female brood fish on the spawning performance of African catfish (Clarias gariepinus)

Abstract

Pitutary gland produces, accumulates and stores gonadotropic hormone which plays active role in ovulation as intermediary between central nervous system and gonads. However, information on the efficacy of pituitary gland from newly spent Clarias gariepinus for inducing ovulation is yet established. The effect of pituitary gland from spent and unspent female fish on the induced breeding performance of Clarias gariepinus was tested. The experiment was set up in a completely randomized design (CRD). Nine (9) brood stock distributed into three treatments were used for the experiment (Treatment 1 was injected with 0.5ml synthetic hormone (Ovulin), Treatment 2 was injected with pituitary from already spent female fish and Treatment 3 was injected with pituitary from unspent fish) and each treatment was replicated three times. The result showed that Treatment 2 had the highest mean values for fecundity rate (122.92%) and was not significantly different from the other treatments. It also has higher value for fertilization rate (60.67%) and high stripping percentage but lower (P < 0.05) hatching rate (13.619) when compared with Treatment 1 which had the highest value for hatching rate (22.79%) followed by Treatment 2 (19.739%) with statistical similarity (P > 0.05). The present research demonstrated that C. gariepinus can successfully be induced to ovulate with pituitary from spent female fish, ensuring maximum use of brood fish and production of high-quality eggs and normal hatchlings.