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Holsteinized Russian Black Pied cattle of the Ural type are bred in the Sverdlovsk region, which is represented by large, highly productive animals with a high genetic potential for productivity. The aim of the study was study holsteinization results of Russian Black Pied cattle in one of the pedigree reproducers of the Sverdlovsk region. Over the past 20 years, there have been significant changes in the rearing heifers’ raising intensity; their live weight at the first insemination increased and their age decreased. In terms of live weight at the first insemination, there was an increase from 2006 to 2013 to over 400 kg; then, when switching to early insemination terms, there was a decrease in live weight to 390 kg. The age of first insemination has decreased since 2000 from 20.2 months to 14.4 months in 2018. An inversely proportional dependence of the milk yield of first heifers on the age of the rearing heifers’ first insemination has been established. An increase in milk yield occurs with a decrease in the age of the first insemination and vice versa, an increase in the age of heifers’ first insemination is observed with a decrease in milk yield. Moreover, this also happened when raising both hybrid heifers and heifers of the new Ural type of Holsteinized Russian Black Pied cattle.

Holsteinized Russian Black Pied cattle of the Ural type are bred in the Sverdlovsk region, which is represented by large, highly productive animals with a high genetic potential for productivity. The purpose of the work was to study the effect of first heifers’ live weight on their productivity and the interrelation between milk yield and milk quality indicators. It was found that there was a positive tendency for an increase in milk yield with an increase in the cows’ live weight from less than 550 kg to 624 kg. The most significant increase in milk yield in cows was in the range from 574 to 599 kg. The difference in milk yield between these groups was 692 kg or 8.1% in favor of animals with live weight of 575-599 kg. An increase in cows’ live weight over 625 kg leads to a decrease in milk yield, which amounted to 2.3%. Changes in correlation are observed from a negative average value in cows with a live weight of less than 550 kg to a positive average value in cows with a live weight of more than 625 kg. In first heifers with live weight from 575 to 599 kg, a very low positive interrelation between live weight and milk yield per lactation was recorded (0.04).