Analysis of the genetic profile of Hereford cattle of different selections for key genes CAPNI, CAST, LEP and MSTN

The study of the genetic structure of Hereford cattle and the identification of polymorphism of key genes associated with economically valuable traits is of great importance for the development of effective breeding programs to improve animal productivity. The article presents a comprehensive analysis of the genetic characteristics of Hereford cattle with an emphasis on the key genes CAPN1, CAST, LEP and MSTN affecting meat qualities. It is shown that the Hereford breed is distinguished by a certain spectrum of genetic variants in the structure of these genes. Reliable associations of individual genotypes with growth rate, meat productivity indicators such as slaughter yield, carcass weight and beef quality were established. The results demonstrate the significant potential for using molecular genetic markers based on gene polymorphism in breeding work with Hereford cattle to improve its breeding and productive qualities. Intrabreed differences in the frequency of allelic variants in the loci of the CAPN1, CAST, LEP and MSTN genes were revealed. In loci 530 and 316 of the CAPN1 gene, the most common homozygous genotypes were CC (0.73) and GG (0.69). For the CAST gene, heterozygous genotypes CG (0.50) and AG (0.49) prevailed in loci 282 and 2959. For the LEP gene, heterozygous genotypes CT were most common in loci 528 (0.53) and 73 (0.84). For the MSTN gene (locus F94L), most animals were homozygous for the wild-type allele CC, and heterozygous genotypes CA were recorded only in single individuals. The frequency of genotypes and alleles in different age and sex groups (cows, bulls and heifers) was also assessed.