Genetic Structure of Different Populations of Walking Catfish (Clarias batrachus L.) in Bangladesh

Information on genetic variation is essential for conservation and stock improvement programs. Seven dinucleotide microsatellite loci were analyzed to reveal genetic variability in three wild populations (Kella beel, Hakaluki haor, and Shobornokhali beel) and one hatchery population of the freshwater walking catfish, Clarias batrachus, in Bangladesh. Upon PCR amplification, the alleles were separated on polyacrylamide gel using a sequencing gel electrophoresis system and visualized by the silver-staining method. The loci were polymorphic (P95) in all the populations. Differences were observed in number and frequency of alleles as well as heterozygosity in the studied populations. Current gene diversity (He) was higher than expected under mutation-drift equilibrium, significantly in the Hakaluki haor and Shobornokhali beel populations, indicating a recent genetic bottleneck. Population…