Reproductive traits of cows of Holstein breed and dynamics of their changes during productive life

Abstract

In order to obtain maximum milk productivity of cows, it is necessary to constantly maintain a high level of reproduction traits of cows in the herd to ensure timely eff ective insemination of them for the annual production of calves. The economy of dairy farming, the level of breeding work, the longevity of animals depends on the state of reproduction of the herd. The purpose of the research was to study the reproductive traits of cows of Holstein breed and the dynamics of their changes during productive life. The research was carried out on the basis of the Agricultural Production Cooperative “Plamya”, a milk production enterprise where Holstein cattle are bred. In order to conduct the study, the indicators of the reproductive traits of cows of the entire productive herd were evaluated in dynamics over 5 years of production use. The material for the analysis of the dynamics of change was taken from the database of the information and analytical system “SELEX-Dairy cattle”. Thus, it was found that during the study period the annual calf crop increased by 102,4 % or by 2 calves. The average number of inseminations per effective one was 2,1 doses over the period. In the period from 2017 to 2021, in the herd the duration of the open days period ranged from 128 to 140 days. The best indicator was noted in 2019. On average, for the herd over a fi ve-year period, there was an increase in the duration of the open days period by 12 days compared to 2017 data. As a result of a comprehensive analysis of the state of reproduction traits of cows in the herd, it was found that the indicators of reproductive trais of cows had a slight deviation from the threshold (normative) values, which indicates a fairly high level of breeding work carried out by specialists of the farm.