Molecular characterization of wild and cultured species of Clarias Scopoli, 1777 and Heterobranchus Geoffroy Saint-Hilaire, 1808 in Zaria, Kaduna State, Nigeria

Abstract

Genetic studies on wild and cultured species of Clarias and Heterobranchus were conducted from August 2012 to January 2013. A total of forty (40) specimens comprising Clarias gariepinus (10), C. anguillaris (5), C. galmaensis (5), Heterobranchus bidorsalis (5), H. longifilis (10) and H. isopterus (5) were obtained from River Galma, Zaria and Bagoma Reservoir, Birnin Gwari (wild) alongside Miracle Fish Farm, Zaria and National Institute for Freshwater Fisheries Research (NIFFR), New Bussa (cultured). A total of eighty (80) samples of muscle and fin tissue of fish were obtained and preserved at -20^oC for molecular analysis. DNA was extracted from the tissues using genomic Quick-gDNA™ MiniPrep (50 Preps) w/ Zymo-Spin IIN Columns DNA extraction kits. The target gene cytochrome b gene (585bp) was amplified according to standard methods. All products were separated, purified and visualized under ultra violet light and documented. Amplification of cytochrome b gene in both fin and muscle tissues of the fish species from a portion of mtDNA of wild and cultured samples was observed. The phylogeny showed two groups, the genotypes clustered together are closely related while their neighbours were joined closely. Although genetic variation was observed between wild and cultured species, there is a close relationship between them, confirming that they are members of the same family Clariidae, with good prospects for culture.

Keywords: Genetics; Clarias species; Heterobranchus species; PCR; Cytochrome b gene