Influence of calpastatin gene on meat productivity of cattle

The article presents the results of the study of the calpastatin (CAST) gene in cattle, encoding a protein of the same name involved in postmortem proteolysis of muscle tissue, as a result of which the tenderness of meat is formed. DNA tests based on the PCR-PDRF method have been developed to identify allelic variants of three CAST polymorphisms at loci 282, 2870 and 2959. Genotyping of the Russian population of the Aberdeen Angus breed (n=138), consisting of bulls (n=57) and cows (n=81) revealed the presence of various genotypes of the studied mutations and sufficiently high frequencies of alleles preferred in terms of productivity (C-CAST_282 – 0.5-0.6; G-CAST_2870 – 0.7; A-CAST_2959 – 0.2-0.4). The correlation analysis of allelic variants of the studied polymorphisms with average daily weight gains of cows and bulls aged from birth to 15 months did not reveal a significant effect of the calpastatin gene on fattening indicators. The effect of CAST_282 and CAST_2959 polymorphisms on post-slaughter histological parameters of bull carcasses was found. The effect of CAST_282 and CAST_2959 polymorphisms on post-slaughter histological parameters of carcasses was found. In bulls with the CC-CAST_282 genotype, compared with heterozygous individuals, statistically significant advantages were observed in terms of the content of muscular (15.9% more) and connective (10.8% less) tissues in the longest back muscle (M. dorsum longissimum), which can be regarded as prerequisites for obtaining more tender beef with high nutritional value. In addition, animals with genotypes CC-CAST_282 and AA-CAST_2959 had significantly larger muscle fiber size compared to analogues of other genotypes. The results obtained allow us to recommend the calpastatin gene as a promising genetic marker for the carcass properties and include it in genomic breeding programs to improve the accuracy of genomic prediction of the properties of beef productivity of cattle.