Use of microsatellite markers in differentiating catfish hybrids (Clarias macrocephalus x C. larias gariepinus) from their parental species

Abstract

This study aimed to develop microsatellite markers that can be used to differentiate catfish hybrids (bighead catfish Clarias macrocephalus x African catfish C. larias gariepinus) from their parental species. Microsatellite primers developed from previous studies were screened and optimized. Six microsatellite markers were selected to amplify samples of bighead catfish (n = 37), African catfish (n = 29), and the hybrids (n = 30). Results show that 4 of 6 loci differ in allele numbers and sizes between the bighead and African catfish. In the other two loci, these two species share one allele that overlaps at a portion of the size range with different allele frequencies. Hybrids’ genotypes are intermediate between those of the parental species. The genetic divergence between bighead and African catfish is high with Fst = 0.59 and Rst = 0.95. Therefore, these 6 microsatellites were applied to successfully distinguish hybrids from their parental species with high accuracy.