Identification of a new potential native Indian cattle breed by population differentiation based on microsatellite markers.

Abstract

India has a rich heritage of rearing cattle where farmers selected native cattle suitable to their local agro-ecological conditions for centuries. It is reflected in 50 indigenous breeds of cattle, besides many lesser known populations not explored so far. It is the need of the hour to characterize such populations to have prudent improvement and conservation options. Thus, present study was carried out to assess the genetic diversity and relationship between an unexplored local cattle population (Kathani) and four established cattle breeds of adjoining area (Gaolao, Kosali, Ongole and Motu) by using 20 FAO recommended microsatellite markers. High variability was recorded in the Kathani population with a total of 198 alleles that varied between 5 (ILSTS11, TGLA22, INRA05) and 17 (ILSTS34) with a mean of 9.9 ± 0.73. The average observed heterozygosity (Ho) was 0.658 ± 0.054. Heterozygote deficiency was not significant (FIS = 0.029 ± 0.063) indicating random mating prevalent across this population. Mean estimates of observed number of alleles and heterozygosity over all the loci and five populations were 9.73 ± 0.421 and 0.617 ± 0.022, respectively. In the overall populations, the homozygote excess (FIT) of 0.293 ± 0.032, was partly due to the homozygote excess within breeds (FIS = 0.121 ± 0.025) and to a larger extent due to high (0.05 < FST < 0.15) genetic differentiation among them (FST = 0.195 ± 0.029). Substantial pairwise Nei's genetic distance and high population differentiation indicated towards separate genetic identity of Kathani cattle. The analysis of genetic structure based on Bayesian approach indicated that the most probable number of clusters is five confirming definitive genetic differentiation among all the popultions. Entire analysis showed that a significant amount of genetic variation is maintained in Kathani, a lesser known cattle population that is distinct from the recognized breeds in the proximity. As this autochthonous cattle plays role in the economic sustainability of a marginal and disadvantaged area, it is important to preserve and develop its breeding.