Diversity analysis of sheep breeds from Southern peninsular and Eastern regions of India

Abstract

Information is presented on the genetic diversity and relationship among six Indian sheep breeds/populations belonging to the Southern peninsular and Eastern agroecological zones, based on microsatellite markers. Parameters of genetic variation, viz., allele diversity, observed heterozygosity, gene diversity and population inbreeding estimates, were calculated for the six breeds. The allele diversity ranged from 6.40 to 7.92, whereas the gene diversity varied from 0.617 to 0.727. The highest allele and gene diversity was observed for Nellore sheep, while the lowest was exhibited by Garole breed. Within population inbreeding estimate (F(IS)) revealed a significant deficit of heterozygotes in Deccani, Madgyal, Nellore and Garole, whereas Ganjam and Chhotanagpuri sheep showed an excess of heterozygotes. The contribution of each breed to the total diversity of the breeds was quantified by the Weitzman approach. The marginal loss of diversity incurred with removal of Nellore and Garole breeds was higher (>27%), whereas removal of Deccani breed resulted in lowest loss of diversity (3.84%) from the set. Estimation of the genetic differentiation (F(ST)) and genetic distance (D(A)) between the pairs of breeds revealed a close relationship between Deccani and Madgyal sheep (F(ST) = 0.017; D(A) = 0.080) and greatest demarcation between Madgyal and Garole breeds (F(ST) = 0.110; D(A) = 0.622). The information generated would help in shaping genetic management and conservation programs for the sheep breeds under consideration.