Genetics features in the populations of Holstein cattle: multiplicative interaction between genes and the elimination of recessive alleles

The article presents the results of the assessment of genetic determination of traits in the breeding of dairy cows of Holstein breed from Germany. The evaluation was conducted on the pedigrees of introduced in the Kaluga region of Holstein heifers. Productive traits of maternal and paternal ancestors were studied, including milk yield, % fat and % protein in milk, as well as heritability coefficients, coefficients of phenotypic (rРР), genetic (rАА) and environmental correlation (rЕЕ), evaluated the difference in milk production cows in comparison with mothers in 4 groups with milk yield to 8000 kg to 12000 kg of milk or more, the degree of influence of the breeding value of the fathers (EBV) on milk yield daughters on the implementation of milk production traits of cows. It has been determined that at low breeding value determination fathers breeding traits genotype mothers ranged from 11,6 (on % protein) to 31,9% (on fat in kg), the share of fathers had from 1,3 to 9,2% of determination. The heritability of traits selection in the sample was 34,2%, of which the share of the factor "ancestor" accounted for 9,1% and the "EBV of father" - 15,3%, the combined effect of these factors - 9,8%. External factors in the implementation of the milk production traits were given to 65,8% of determination. On the basis of the survey concluded that the phenotypic expression of the genetic correlation is complex multiplicative effect of the interaction between genes and the interaction of the genotype with external factors.