Heterozygosity as a factor of increasing the meat productivity of kalmyk steers

ABSTRACT The present work carried out full-genome SNP genotyping of 16-month-old Kalmyk steers to study their productive characteristics and beef quality indicators in the leading farms of the Republic of Kalmykia (Group I was located at the Agrofirma Aduchi farm; Group II at the Kirovsky breeding plant, and Group III at the Plodovitoye agricultural cooperative). As a result of investigating the frequencies of some homozygous alleles, the study established that the heterozygous allele A/A varied considerably along the lines from 0.2785 to 0.3146, while B/B varied from 0.3697 to 0.4125. Meanwhile, the heterozygous allele A/B varied from 0.2986 to 0.3197. Estimated inbreeding coefficients were 1.35, 1.28 and 1.27%. The conducted studies established a higher natural resistance determined by lysozyme, bactericidal and phagocytic activities of steers raised at the Agrofirma Aduchi as farm than their counterparts at the other agricultural enterprises. Over the entire period of the experiment, the steers from 8 to 16 months of age in Group I exceeded the indices of their counterparts in Groups II and III by 30.46g, or 3.31% and 38.04g, or 4.16%, respectively. It is concluded that an increase in the heterozygosity of the studied Kalmyk steers not only results in higher meat productivity, but also improves the quality of carcass and beef quality, increases the yield of more valuable meat grades, and optimizes the fractional composition of proteins.