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Since 2021, the Sverdlovsk region has switched to the cultivation and use of dairy cattle of the Holstein breed, obtained as a result of long-term use of the global gene pool of Holstein bulls. Evaluation of the effectiveness of rearing repair heifers from different servicing bulls is relevant and has practical significance. As a result of the conducted research, it was found that repair heifers increased their live weight with age, which by the age of 18 months reached from 508.0 kg (daughter of Thunderlight bull) to 529.3 kg (daughter of Seiner bull). The daughters of the Seiner bull have a higher growth rate. The daughters of the Thunderlight bull had lower live weight indicators for growth periods. The patterns of change in the average daily body weight gains in heifers-daughters of the evaluated servicing bulls were the same and corresponded to the general patterns of animal growth and development. The cultivation of repair young animals on the farm is profitable at a profitability level of 16.5-21.6%. Thus, the servicing bull has an impact on the growth and development of repair heifers, daughters, who are used to renew the herd. They differ in their features, despite the general patterns of growth and have different growth rates.

Sverdlovsk region is one of the leading regions in milk production. The main livestock of dairy cattle is represented by the Holstein breed, obtained as a result of long-term use of the global gene pool of Holstein servicing bulls. The assessment of the productive qualities of dairy cattle of the Holstein breed, including consideration of linear origin, is relevant and has practical significance. As a result of the conducted research, it was found that the farm is dominated by the number of cows of the Vis Back Ideal line, which account for more than 65.8% of the total number of cows. There is an unreliable insignificant difference in favor of cows of the Reflection Sovering line between groups of animals of different genealogical lines for the first and third lactation. With age, there is a decrease in milk quality indicators, such as FMF and PMF in milk from cows of all genealogical lines, which confirms the natural negative relationship between milk yield and milk quality indicators. The absorption of dairy black-and–white cattle of the domestic breed by the gene pool of the world’s most abundantly dairy breed, the Holstein, led to an increase in milk yields and the milk yield coefficient of these cows is much higher than 1000 kg. Despite the fact that the difference in milk yield is unreliable and the variation of the trait within each group along the line is quite significant, this is indicated by indirect traits such as the coefficient of milk production, milk yield for full-age lactation, etc., origin affects the productive qualities of cows.

Purebred stud bulls of a related Holstein breed are widely used when breeding domestic black-and-white cattle breeds. Results’ evaluation of using these stud bulls by offspring quality is relevant and has practical significance. Stud bulls of the Vis Back Ideal 1013415 line were evaluated in one of the breeding farms of the Moscow region. As a result, it was found that all the evaluated stud bulls had a high breeding value. Bulls Trubach 174 - A1; Nog Odin-M 490626 - A1; Lowlands-M 427373367 – A2 were assigned categories by milk yield, bulls Memory-M 54215651 – B2; Fern-M 107901925 - B1; Lowlands-M 427373367 – B1. The evaluation of nutrients’ yield with milk showed that when using the offspring of Memory-M 54215651 bull, negative results were obtained despite that it has a category B2. According to the nutrients’ yield with milk. Thus, stud bulls of the Vis Back Ideal 1013415 line: Trubach 174; Nog Odin-M 490626; Memory-M 54215651; Fern-M 107901925; Lowlands-M 427373367 can be used on the farm considering their breeding value. Lowlands-M 427373367 bull with category A2 B1 requires wider use.

The Ural type of the domestic black-and-white breed is characterized by high productivity and good suitability for use in the conditions of industrial milk technology. During its breeding, the use of purebred bulls-producers of the Holstein breed of both domestic and foreign breeding continues. As a result of the conducted research, it was found that the productivity of cows changes significantly with age. Milk yield for 305 days of lactation increases from 1 lactation to 3 lactation, and then decreases by 369 kg or 3.8% in the fourth, relative to the third, and by 2090 kg or 22.2% in the fifth, relative to the fourth. The productivity of full-aged cows is higher than that of young cows and can remain at a high level for a long period. The quality indicators of milk changed upward from the first to the fifth lactation. High correlation coefficients were established by the conjugation of milk quality indicators with each other, regardless of lactation. They ranged from 0.364 (2 lactation) to 0.533 (1 lactation). That is, a decrease or increase in MJ in milk will lead to the same change in MDB.