Survival, Growth and Feed Utilization of the Reciprocal Hybrids of Clarias gariepinus (Burchell, 1822) and Heterobranchus bidorsalis (Geoffroy, 1809) in Concrete Tanks

摘要

The production of fish seed of good quality remains one of the major challenges of modern aquaculture in Nigeria and sub-Saharan Africa. This study was conducted to determine the survival rate, fertilization rate, growth performance and feed utilization of the reciprocal hybrids of Clarias gariepinus and Heterobranchus, bidorsalis . Two genetic crosses were made: C. gariepinus x H. bidorsalis and H. bidorsalis x C. gariepinus . The experiment was conducted in two phases; the first phase was the artificial propagation of the fish species using synthetic hormone and rearing the fry for 14 days; the second phase was rearing the 14 days old fry for 35 days. The first phase of the experiment examined the survival of frys in each experimental unit (genetic cross) while in the second phase, growth and nutrient utilization were investigated. The result showed that the highest (%) fertilization (81.32±4.76%), hatching rate (73.89±4.45) and (%) survival (78.36±4.79%) occurred in H. bidorsalis x C. gariepinus and the differences were significant (0.05). Percentage weight gain and specific growth rate were the two growth and nutrient utilization parameters that showed significant difference (0.05) between the two reciprocal hybrids. The result of this study shows that the reciprocal hybrids of C. gariepinus and H. bidorsalis can be used for commercial aquacultural practices.