Economically useful traits of cows received from different sires

Abstract

When breeding Black-and-White holstinized cattle, the sperm of highly productive sires with high productivity potential of maternal ancestors, including Holstein breed, is used. Evaluation of sires by the quality of off spring is the most accurate method of determining the actual breeding value. The purpose of the work was to evaluate the economically useful traits of cows obtained from diff erent sires. The research was carried out in one of the breeding farms typical for the Sverdlovsk region for the breeding of Black-and-White cattle with a high proportion of blood in Holstein breed. The evaluation of three Holstein sires Zhadon 60044914, Onward 4512 and Plateau 62297905 on the quality of off spring was carried out by comparing the productivity of cows-daughters with their herdmates. It is established that when selecting sires for work in the herd, group selection of sires of the same type in terms of productive traits of maternal ancestors is used. This leads to almost equal milk yields for their daughters. There was also no signifi cant diff erence in milk quality indicators. When comparing the productivity of the cows-daughters of sires for the fi rst lactation with their herdmates, a certain diff erence was established, both in milk yield for 305 days of lactation, and in the mass fraction of fat and protein in milk. The cows-daughters of sire Onward 4512 turned out to be the best relative to herdmates in milk yield and mass fraction of fat in milk. The daughters of the sires Zhadon 60044914 and Plateau 62297905 had productivity lower than their herdmates by 315 and 127 kg, respectively. The daughters of the sire Plateau 62297905 surpassed their herdmates in terms of the mass fraction of fat and protein in milk. The level of profi tability of milk production for the highest lactation was 58,9–66,6 % and was higher in the group of cows–daughters of the sire Zhadon 60044914.