COMPARATIVE ANALYSIS OF THE HOLSTEIN CATTLE POPULATION BY THE METHOD OF PRINCIPAL COMPONENTS

Abstract

Nowadays, the so-called index selection is becoming more and more relevant. However, it is a well-known fact that one trait in a particular population can be manifested to varying degrees. Therefore, a more correct and promising direction of breeding will be the development of methods for evaluating animals that take into account the characteristics of a particular herd. The purpose of the research presented in the article was a comparative evaluation by the method of principal components of Holstein cows, taking into account genealogy and genetic affiliation. In 2022 based on the data of the “Selex-Russia” pedigree recording, the cows of OOO “Chapaevskoe” were selected, taking into account their genealogical (3 lines) and genetic affiliation (3 bulls in each line). In total, 9 groups of 15 head were formed. Next, 20 traits were identified, which we used for a comparative evaluation of animals – the main parameters of productivity and reproductive capacities for 2 lactation periods. When calculating the complex index (CI), 8 components were identified, the average values of which we used in the comparative evaluation of genealogical and genetic groups of CI. It was found that the spread of parameters in the groups, taking into account their belonging to the servicing bull, is quite small (lim=0,063-0,071), however, according to the set of traits, the bulls number 125167552, 125571728, 125932660, which belonged to the Vis Beck Ideal line, had the best results. At the same time, the variability of the results along the lines was in the range of 0,065–0,0694. This also indicates the consolidation of traits in the studied livestock population. On the basis of a single-factor analysis of variance, the influence of factors such as belonging to a line and to a specific genetic group on the studied traits was established.