Application of microsatellite markers in identifying genetic relationship among different swine populations in Sri Lanka

Five different swine populations in Sri Lanka including Village pigs, wild boar and exotic breeds such as Large White, Landrace and Duroc were selected for this genetic study. Fifteen microsatellite markers recommended by the FAO (Food and Agriculture Organization) and ISAG (International Society of Animal Genetics) were employed to analyze genetic distance among different swine populations. A total of 120 samples of pigs were collected from various locations in Sri Lanka where village pigs and wild boar could be found. The MICROSAT and PHYLIP computer packages were used to estimate the allelic frequency and construct the phylogenetic tree. The phylogenetic tree was constructed using Neighbor-joining approach with 1000 bootstrap values, The results of the study revealed that 138 alleles were found at 15 loci screened across five swine populations Among them 11 were polymorphic and rest were monomorphic. The polymorphic alleles ranged between 2-4 alleles per locus. The genetic distance between village pig and wild boar (0.091) was closer than between Large White (0.261), Landrace (0.241) and Duroc (0.268). According to the dendogram the village pig and wild boar populations clearly diverged front exotic breeds. In the phylogenetic tree, high distances observed were separating exotic pig populations from the other two populations of village pigs and wild boar. Further, the village pigs and wild boar clustered separately. Based on these findings it is proposed that the village pigs and wild boars may be recognized as distinct population for breeding or conservation purpose. AGRIEAST 2010 (9) p.6-10