COMPARATIVE STUDY OF SYNTHETIC HORMONE AND CARP PITUITARY GLAND IN INDUCED BREEDING OF AFRICAN CATFISH (Clarias gariepinus) IN HATCHERY

Abstract

ABSTRACT The study was initiated to evaluate the effectiveness of carp pituitary gland (PG), and synthetic hormone ovaprim (OV) on spawning success of Clarias gariepinus in a hatchery. In total, 21 female and 9 male mature catfish were used for the study. The study examined the mean fecundity, fertility rate, egg hatching and survival of C.gariepinus using different hormones. The mean fecundity was calculated from the total weight of eggs released. The percentage of fertilization was determined based on the surviving embryos 45 second after fertilization. The hatching percentage was calculated from the total number of fertilized eggs, while the percentage of survival rate was determined by physical counting after 14 days feeding with Artemia nauplii. The mean number of eggs ovulated was higher in pituitary gland injected catfish than ovaprim treated catfish. However, in the control group, one brood fish was ovulated poor quality eggs out of three female fish but was not hatched at all. The highest rate of fertilization, 73.2 %, was observed in ovaprim treated catfish compared to 72 % in carp pituitary treated catfish. On the other hand, ovaprim treated fish showed much higher hatching rate (89%) than the pituitary treated catfish (69%). Mean survival rate of fry was higher in Ovaprim (85 %) than in carp pituitary gland treated fish (79 %). However, Ovaprim treated fish showed slightly higher hatching and survival success as compared to carp pituitary gland but no significant differences in stimulating effect (P > 0.05) was obsereved in all parameters investigated.