Authors : A.A. Akinwande, O.A. Fagbenro and O.T. Adebayo
Abstract: Interspecific hybrids of Clarias gariepinus and Clarias anguillaris were produced by employing the technique of hypophysation and dry stripping. Investigations on their aquaculture potential in terms of growth and survival were carried out. About 2 weeks old fry (0.06±0.02 g) of the parental Clarias species and their interspecific hybrids were stocked in hapa nets (1 m2) suspended in outdoor earthen ponds (16 m2) in triplicates for a rearing period of 56 days. Weight increase in the parentals and the reciprocal hybrids were assessed fortnightly. Studies revealed that the growth of the hybrids were intermediate to the parental Clarias gariepinus but higher than Clarias anguillaris. The weight gain attained by Clarias gariepinus, Clarias anguillaris, C. gariepinus (♂) x C. anguillaris (♀) and C. anguillaris (♂) x C. gariepinus (♀) were 3.18, 2.99, 3.16 and 3.05 g, respectively. Among the interspecific hybrids, the growth of C. gariepinus (♂) x C. gariepinus (♀) was higher than its reciprocal hybrid cross of C. anguillaris (♂) x C. gariepinus(♀). Survival of the reciprocal hybrid crosses at 8 weeks were also intermediate to that of the parental Clarias gariepinus but higher than C. anguillaris. Hybrids displayed positive heterosis for weight gain (0.65%) and survival (0.80%). The superiority of these growth traits of the hybrid groups at least over one of the parentals indicates hybrid vigor. Hence, hybrids in both directions appear to have considerable potential for use in aquaculture.
A.A. Akinwande, O.A. Fagbenro and O.T. Adebayo, 2011. Growth and Heterosis in Reciprocal Clarias Hybrids Between Clarias gariepinus and Clarias anguillaris. Journal of Fisheries International, 6: 67-70.