Animals breeding efficiency according to the phenotype of their offspring

Abstract

The paper aims to identify the best animals with the optimal variant of selection traits in dairy cattle breeding by studying the breeding and genetic parameters (M, m, s, Cv, r) of the basic dairy and reproductive traits of individuals and genetic groups, which make it possible to comprehensively assess the breeding efficiency of animals according to the phenotype of their offspring. The paper justifies characteristics of the seed bulls fixed for the breeding stock, and proposes basic principles of selection. The range of evaluated traits was expanded - from milk productivity and reproductive qualities to health indicators (longevity, somatic cell content in milk) and estimate of the animal body type (exterior). The correlation coefficient (g) between fat and protein was not standard: when selecting animals with a high content of protein in milk, only in 20% of cases the selected cows have a high level of fat.