Evaluation of the efficiency of using black-mottled cows of the Ural type

Abstract The article assumes that in the Sverdlovsk region, breeding bulls of the Holstein breed with high efficiency according to their maternal ancestors were used on the breeding stock of the black-mottled breed of the Ural spawn. Animals of this type are of high efficiency. The efficiency evaluation of Ural type cows is urgent. The aim of the work is to evaluate the efficiency of the new genotype cows in terms of their milk yield qualities. It has been found that dairy cows show high milk yields. In accordance with physiological laws, they increase until the fourth lactation, and then gradually go down. The first insemination of replacement heifers on the farm is carried out at the age of 18-19 months with a live weight of over 400 kg. This makes it possible to breed healthy strong animals capable of breeding for a long time and having high milk yield. The maximum milk yield is from 21 kg to 1986 kg (from 0.2% to 35.3%); it is more than the actual one. The farm has reserves for increasing milk yield due to measures for the milk efficiency of the first-year heifers and other cows. It will significantly increase the milk yield in the third and further lactation. The authors calculated the life-long milk yield. It turned out that in fact, 84,450 kg of milk can be obtained from a dairy cow during 10 lactations. The efficiency potential of lifetime productivity, based on the maximum milk yield per lactation, was 7077 kg or 8.4% higher. The predicted potential shows that 104 101 kg of milk can be obtained from a dairy cow during 11 lactations. The efficiency fluctuations by lactation are significant; and from the first to the 5th lactation they exceed 150% of the minimum milk yield of dairy cows to the maximum in the same lactation. So, it is possible to make a conclusion about the great changeability of this feature in the herd and the great possibilities of selection at carrying out selection and breeding work on the farm.