Slaughterindicators of the Hereford x Black -andwhite bulls depending on genotypes of miostatin genes (MSTN)

Abstract

Many factors influence the efficiency of livestock production, one of the most significant is the genetic potential of animals used in breeding. Most economically significant indicators such as meat production are polygenic and can be determined by many genes, one of the them is the myostatin gene (MSTN) influencing the meat production.In our research we studied the slaughter indexes of Hereford x black-and-white bulls depending on the genotypes of the myostatin gene (MSTN). Bulls with the MSTN^BB genotype had the higher the slaughter indexes than those of the MSTN^AA genotypes.They excelled animals with alternative genotypes by the mass of paired carcass on 26.1 kg or 9.4% (P <0.01), by carcass yield - on 3.6 %. (P <0.05), by slaughter weight - on 23.2 kg or 7.6% (P <0.05), by slaughter yield - on 3 %(P<0.05).Bulls with MSTN^AA genotype excelled animals with MSTN^AA genotypes: by the mass of paired carcass on 19.5 kg or 7% (P <0.05), by carcass yield on 2.9% (P> 0.05), by slaughter weight on 17.5 kg or 5.7% (P <0.05), by slaughter yield on 2.4%.(P> 0.05).Analysis of the morphological composition of half-carcasses of experimental animals showed that carcasses with a higher yield of meat were received from the bulls with a genotype MSTN^BB at the age of 16 months in comparison with the peers of the other experimental groups. Thus, in meat half-carcasses of the bulls with genotype of MSTN^BB genes, the content of the meat was higher by 12.7 kg or 11.1% (P <0.001), in half-carcasses of animals with genotype of MSTN^AB genes - by 8.1 kg or 7.1% (P> 0.05) than in peers of the first group. Bulls with genotype of MSTN^BB genes exceeded their peers with alternative genotypes by the coefficient of meat on 9.8% and 4.8% respectively.