Performance and characteristics of the progenies from the reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878) and Clarias gariepinus (Burchell, 1822)

Abstract

This study was designed to evaluate the culture performance and characteristics of the offspring from the reciprocal crosses of Pangasianodon hypophthalmus and Clarias gariepinus. The hybrid ♀C. gariepinus × ♂P. hypophthalmus (Clariothalmus) gave better hatchability than ♀P. hypophthalmus × ♂C. gariepinus (Pangapinus), similar to P. hypophthalmus but lower than the value recorded in the C. gariepinus. Cytogenetic analysis of the Clariothalmus reveals the presence of diploid hybrid (2n = 58 representing 60% of the population) and gynogenetic diploid offspring (2n = 56 representing 40% of the population), while, Pangapinus offspring were all gynogenetic diploid (2n = 60). Hence, the diploid hybrid exhibited phenotypic divergence from both parents, while the gynogenetic diploids were phenotypically indistinguishable from the maternal parent and had similar meristic counts. After 112 days of culture, gynogenetic diploid of the Clariothalmus offspring had better growth than the other crosses, however, cannibalism and aggressive behaviour was higher in this group of fish compared to other. Hence, culturing the diploid hybrid Clariothalmus separately from its gynogenetic diploid may be a management practice of interest as demonstrated in this study. This study provides evidence to support the success of hybridization between African and Asian catfish in one direction and demonstrates their potential for culture.