Dynamics of live weight of young animals and cows of black-and-white breed in JSC "Agrofirma Mtsensk" of the Oryol region

In the structure of the number of dairy cattle in the Oryol region, the Black-and-White breed occupies a leading place, but it was absorbed by Holstein sires. As a result, the proportion of Holstein breed genes in the breeding array increased to 90% and more. There was a need to register this massif as a Holstein breed. To do this, we assessed the intensity of growth of bred young animals and cows in JSC Agrofirma Mtsensk, Oryol region. As a result of the research, it was determined that in recent years on the farm, by the age of 18 months, heifers reached 432-446 kg. In 2020, the live weight of cows from 1 to 3 lactations increased according to the dependence that can be expressed by a polynomial regression equation y=22x2-44x+562 , in 2021, the live weight of cows from 1 to 3 lactations increased linearly - y=43.5x+515 , and the indicators of cows in terms of live weight by the 3rd lactation became slightly higher - 647 kg. Thus, we can conclude that the Holsteins have a significant impact on the increase in the live weight of the bred livestock and its compliance with the standards of the Holstein breed.