The aim of the study was to establish the characteristics of the meat productivity of steers obtained from crossing Simmental cows with Aberdeen-Angus and Kalmyk bulls, depending on the cultivation technology. Scientific and economic experiments were conducted in three farms of the Karachay-Cherkess Republic: LLC firm Hammer (experience 1); SEC PZ Zarya -1 (experience 2) LLC Yugagrohim (experience 3) in 2021-2022. For the entire period of cultivation in crossbreeds (? Simmental + ? Aberdeen-Angus) in the first experiment, the average daily increase was 711 g, 8.5 energy feed units were spent on 1 kg of increase, while the increase in Simmental bulls was 655 g per day, 10.4 EQ was spent on 1 kg of increase, or 22.35% more. The crossbreeds (? Simmental + ? Kalmyk) were closer to the bulls of the Simmental breed in terms of growth and payment of feed. In the first, second and third experiments, the crossbreeds (? Simmental + ? Aberdeen-Angus) outperformed purebred simmentals by: pre-slaughter live weight by 29.7 (P>0.999), 12.1 and 13.9 (P>0.99) kg; the mass of the paired carcass by -18.5, 8.9 and 8.6 kg (P>0.99 – 0.999); internal fat weight by – 3.1 (P>0.999), 0.6 and 2.4 (P>0.99) kg; slaughter weight by – 21.6, 9.5 and 10.2 kg (P>0.99–0.999); slaughter yield by -1,07,0,66 and 0.49 abs.%; half-carcass weight by 9.1, 4,5. and 4.5 kg (P>0.99–0.999); muscle mass by -6.13 (P>0.999), 3.0 (P>0.95) and 3.74 (P>0.99) kg; adipose tissue by–3.75 (P>0.99), 1.91 and 0.58 kg, respectively.

By regulating the nutritional level of young animals in the postembryonic period, it is possible to change the growth rate of animals, the forming of meatiness and the ratio of the most important tissues in the carcass. The aim of the work was to establish the influence of different nutritional levels on the growth, development, meat productivity of Black Pied young cattle of different ages. The scheme of young animals growing was as follows: group 1– increased nutritional level up to 14 months of age; group 1-a – young animals were grown in the same way as young animals of group 1 up to 8 months (increased nutritional level), and from 8 to 14 months they were on average nutrition; group 2 – average nutrition was up to 14 months; group 2-a – average nutrition was up to 8 months, and from 8 to 14 months – an increased nutritional level. During 14 months of growing, it was spent on each head in group 1 – 2114.8; in 2-a – 1888.1; in 1-a – 1919.0; in group 2 – 1692.3 energetic feed units. During 18 months of growing, it was spent respectively: in group 1 – 3673.2; in 2-a – 3345.6; in 1-a – 3197.4 and in group 2 – 3240.0 energetic feed units. Young animals of group 1, which had improved nutrition, on average gained 837 g daily for the entire period, which is more than young animals of groups 2-a, 1-a and 2 by 124, 161 and 170 g (B> 0.999), respectively. With a high nutritional level of young cattle for meat, there is a dramatic increase in meat productivity and an improvement in the quality of meat. Moreover, the cost of feed for the output is reducing and the economic efficiency of livestock breeding is increasing. Nutritional level has a differentiated effect on the development of individual organs and tissues. The growth of the same tissue in different parts of the carcass with insufficient nutrition is delayed to varying degrees.

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This article presents the results of a study on the search and development of the most optimal breed for beef production and growing technology using fattening and fattening in the conditions of the Karachay-Cherkess Republic. An experiment was conducted at Hammer LLC, the object of which was the bulls of the Aberdeen-Angus, Swiss and Kalmyk breeds bred in the region. From birth to 18 months of age, bull-calves of all breeds were distinguished by high payment for feed by increments. They spent 5.4-6 feed units per kilogram of growth. The feed fed to one bull for 18 months of rearing contained 2918-3235 feed. units and 295-325 kg of digestible protein. Live weight at the age of 18 months in bulls of the Aberdeen-Angus breed was 589.4 kg, which is more by 28.4 and 68.4 kg than in bulls of Swiss and Kalmyk breeds, respectively. The slaughter yield in young animals of all breeds was high from 60.1 to 61.6%. However, heavier carcasses were obtained from bulls of the Aberdeen-Angus breed, which is higher than that of Swiss and Kalmyk bulls by 6% and 12.9% at 18 months, respectively. The calorie content of carcass pulp in animals of all breeds was quite high (2274-2346 kcal at the age of 15.5 months and 2470-2700 kcal at 18 months).When determining the economic efficiency of growing bulls up to 15.5 and 18 months of age, it was revealed that the highest payment for feed was shown by animals of the Aberdeen Angus breed, which spent 11.1 per 1 kg of live weight gain for 15.5 and 18 months of growing, respectively.and 10.7 feed units. At the same time, the Aberdeen Angus breed had the minimum production costs per unit of production. In bulls at the age of 15.5 months, they were 5.3 and 17.0% lower than in Swiss and Kalmyk cattle, and at the age of 18 months, they were 11.1 and 20.3% lower, respectively.