Morpho-Genetic Relatedness Among Wild and Cultured Clarias gariepinus (Buchell, 1822) Collected from Ogbomoso, South-western Nigeria.

Abstract

Clarias species used in aquaculture are suffering from inbreeding depression with its attendant poor reproductive attributes and there is the need to explore the natural population to improve reproductive performance. Therefore, this work aimed at evaluating the morpho-genetic variability among wild and cultured Clarias garipinus available in Ogbomoso, South-Western, Nigeria. Fifty C. gariepinus samples were obtained from the wild and cultured populations and only ten were favoured for this work. The DNA was extracted from the caudal peduncles of five representatives of the two sampled populations and DNA amplification was done using cytochrome oxidase region’s COX1. Predictive Analytics Software version 20.0 was used for data analyses. Results showed that virtually all morphometric parameters measured were significantly higher in the cultured populations compared to the wild except the dorsal fin length (p=0.346). The A260/280 ratio ranges from 1.85 (C1) to 2.11 (W2), with most samples having a ratio close to 2.0, indicating high-purity DNA, which is around standard recommended DNA concentration for the amplification. The DNA amplified at 700 bp from a portion of mitochondrial DNA (mtDNA) of wild and cultured Clarias gariepinus. The genetic distance between each strain is represented by the length of the branch that connects them. Therefore, these suggest that C. gariepinus breeders and farmers should source C. gariepinus species from the wild in order to genetically enrich the gene pool. Additionally, head region-based morphometric traits might be more informative in distinguishing wild and cultured populations of C. gariepinus.