Survival, growth and feed utilization of the reciprocal hybrids of Clarias gariepinus (Burchell, 1822) and Heterobranchus bidorsalis (Geoffroy, 1809) in concrete tanks

An experiment 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 (male) x H. bidorsalis (female)(Clariabranchus) and H. bidorsalis male x C. gariepinusmale (Heteroclarias. The experiment was divided into two phases; artificial propagation of the fish species using synthetic hormone and rearing the fry for 14 days; and rearing the 14 days old fry for 35 days. In the first phase of the experiment, survival of frys were estimated in each experimental unit (genetic cross) while in the second phase, growth and nutrient utilization were investigated. The result revealed that the highest %fertilization, hatching rate and %survival occurred in H. bidorsalisfemale x C. gariepinus male (Heteroclarias) and the differences were significant (p < 0.05). Percentage weight gain and specific growth rate were significantly (p < 0.05) higher in Clariabranchus than Heteroclarias. Based on the result of this study, reciprocal hybrids of Clarias gariepinus and Heterobranchus, bidorsalis is recommended for commercial aquacultural practices.