Genetic markers in sheep breeding

Abstract

The priority direction in developing domestic sheep breeding is the creation of new and improved breeding forms that combine high meat and wool productivity rates with good adaptive qualities to breeding conditions. In Russia, 404.2 thousand heads of coarse-wool sheep breeds and 21.2 thousand heads of semi-coarse-wool sheep are concentrated on breeding farms. Compared to 2000, the number of breeding animals increased by 5.0 times, while the yield of lambs for slaughter per 100 breeding queens increased by 5.7 times. One way to increase the selection and breeding work with breeds is to search and use genetic markers of productivity and vitality. The work aimed to summarise and analyse information about the genetic polymorphism of genes associated with traits of productivity and disease resistance in different breeds of sheep. The results of studies of polymorphic variants of genes related to the growth energy of young animals, wool quality and meat productivity in sheep are presented. The calpastatin (CAST) gene is described, which is associated with meat productivity and tenderness of meat the KRT (keratins) gene - with wool productivity and wool quality, the growth hormone gene GH and the differential growth factor gene GDF9 - with the regulation of growth and development, reproductive qualities and meat production, sheep productivity. In most studies, the predominant genotype in all breeds is CASTMM. The frequency of genotypes for the KRT and GH genes in breeds of different directions of productivity varies significantly. The relationship of genotypes CAST, GН, and GDF9 with economically valuable traits is described, making it possible to consider their genetic markers.