Productive traits of the daughters of bulls-sires of the Holstein breed when used in the orеl population of dairy cattle

The Holstein breed is one of the most widespread breeds in the world. This is due to its productive and adaptive qualities. However, in our country, for a long time, scientists and practitioners were ambivalent about the Holstein breed. This was due to the problems that arose when crossing Holsteins with local breeds. At present, in Russia, preference is given to the Holstein breed for intensive milk production. At the same time, many of the introduced tribal arrays are poorly studied. The purpose of this publication was to study the breeding value of breeding sires, the semen of which is used in the Orеl population of dairy cattle. The productivity of animal lines of W.B. Ideal, M. Chieftain, R. Sovereign (n = 891). It was determined that there were no significant differences in the growth rate of heifers among the lines. In total, according to the pedigrees, more than 100 fathers-sires made a genetic contribution to the herd. The herd used the semen of 17 breeding bulls with the superiority of daughters over the herd averages from 690 kg to 2242 kg of milk. From 17 breeding bulls (milk yield improvers) 8 daughters gave more than 7000 kg of milk in 305 days of lactation, and 9 daughters gave more than 8000 kg of milk. At the same time, the fat content of the daughters' milk ranged from 3.89% (Alta Madison 3004886505 and Trader 66228157) to 4.02% (L.T.B. Fineley 61741713). Protein in milk was 3.26-3.30%. Milk flow rate varied in daughters from 1,940 kg / min (D.A. Tyson 66133528) to 2,290 kg / min (Comstar Lekzakt 102482659). The daughters' first lactation body weight was stable, ranging from 544.1 to 572.4 kg. In general, in the future, the selection according to milk fat content, milk flow rate and % of protein in milk deserves special attention.