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.

Genetic relationships among four Turkish sheep breeds using microsatellites

“…The total allele numbers, mean allele number per locus, effective number of alleles, and mean heterozygosity (0.87) observed in 17 microsatellite loci were higher than those reported in the literature (16)(17)(18)(19)(20)(21)(22)(23)(24). These findings indicate that the used microsatellite markers can be reliably used to measure genetic diversity for these breeds.…”

Morphological and microsatellite DNA diversity of Nigerian indigenous sheep

“…Marked differences were observed in the morphological traits of the sheep breeds in this study. The present values of BW and linear body measurements of Yankasa, Uda and Balami sheep are higher than the range of values reported for Ganjam sheep in India by Arora et al [10]. Most researchers consider an organism’s phenotype as a multivariate set of variables and the covariation of traits an important analytical consideration [22].…”

“…However, the values fall within the range reported for other sheep breeds. Arora et al [10] reported values for observed number of alleles in the range of 7 and 25 with a mean value of 13.96. The small average number of alleles per locus in Uda and WAD may be the result of a small number of founder animals since the degree of genetic variability among these animals will be small even in the presence of crossbreeding and mutation rates [32].…”

“…These values (0.658 to 0.902) are within the range observed in other sheep breeds in other parts of the world. Arora et al [10] observed 0.594 to 0.922 for sheep breeds from Southern Peninsular and Eastern regions of India. Values for Italian sheep breeds are 0.761 to 0.805 [39] and European sheep breeds ranged from 0.538 to 0.807 [40].…”

“…Dossa et al [16] reported that morphological measurements such as heart girth, height at withers and body length can be used for rapid selection of large size individuals in the field to enable the establishment of elite flocks. In addition, microsatellites have been used successfully over the years to characterize the genetic diversity of sheep populations in China [12], Ethiopia [5], Europe and Middle East [7-9,17], India [10,11,18] and Brazil [13]. …”