MEAT QUALITIES OF RUSSIAN MEAT MERINO SHEEP AND THEIR ASSOCIATION WITH THE CAST GENE (CALPASTATIN)

Abstract

Genotyping and meat productivity were studied in a flock of a sheep population of the meat and wool breed (Russian Meat Merino). The experiment was conducted on the basis of a breeding farm of the Stavropol Territory, Arzgirsky District, Lenin Collective Breeding Farm. The relationship between the polymorphisms of the CAST gene and the quality characteristics of the meat of these animals was studied. As a result, the frequency of alleles and genotypes was established in the locus of the CAST (calpastatin) meatiness hormone gene, as well as their association with meat productivity characteristics, carcass morphology, and internal organs development. The aim of our research was to show the genetic association of the meatiness gene polymorphism (CAST) with meat productivity of sheep. The object of our research was 100 young sheep. At the beginning of the experiment, genotyping of the sheep population was carried out, and then a control slaughter of animals. During the scientific research of the CAST (calpastatin) gene polymorphism, the following genotype distribution frequency was found: animal units with the MM alleles of the homozygous variant – 67,0 %, and with the MN alleles – only 33,0 %.

It was found that the examined animal population did not have the homozygous NN genotype. When analyzing the obtained results of the control slaughter of young rams, it was found that carriers with the heterozygous genotype exceeded the live weight parameters by 2,4  % of the homozygous alleles of the MM genotype. They also had 4.2 % higher hot carcass weight and slaughter weight. The pattern we discovered also found its superiority in the high slaughter yield, exceeding by 1,2 abs. percent of animal units – carriers of the homozygous MM genotype. The obtained scientific data showed that the presence of the heterozygous MN genotype in the meat and wool sheep population had a positive effect on the quality and quantity of meat. In order to increase the meat productivity of the meat and wool sheep of the Russian Meat Merino breed, genotyping should be carried out using genetic markers and animals with the desired genotype should be identified.