Formation of bull-producing groups of cows in Ayrshire breed using genomically evaluated candidates

Purpose: Assessment of the quality of the well-producing groups, the productivity of candidates for the first lactation, the possibility of using genomically estimated cows to increase the parameters of mothers of future bulls, to analyze the quality of the offspring of bulls of various origins.

Materials and methods. Research was performed on the basis of breeding plants Karelia Megrega (1455 cows) and Ilinskoe (1200 cows). Analyzed the productivity of bob-producing groups isolated on trivials. 66 Genomically estimated flaws were delivered from Finland after calving for milk productivity for the first lactation with local peers. In assessing the quality of the offspring of producers of different origin, the productivity of 1441 of the daughter of imported bulls and 620 daughters of domestic bulls took place. The degree of differences was assessed by the results of biometric processing of indicators.

Results. At the Ilyinskoye dairy farm, the milk yield for lactation of cows of the bull-producing group is 11977 kg of milk with a fat content of 4.33%, protein content of 3.22%. There are 11119 kg of milk at the Megrega farm, 4.42% and 3.23%, respectively. A significant number of individuals (14.7-19.8%) with a milk yield above 9,000 kg of milk, which are a source of replenishment of bull-producing groups, were identified at breeding farms among the first heifers. The possibility of forming and improving the quality of bull-producing groups of cows at the expense of their own livestock is noted, provided that the factors of feeding and keeping animals, increasing the fat content and protein content of milk are optimized.

Comparison of productivity indicators of imported "genomic" cows with local peers gave mixed results. At the Ilyinskoye farm, "genomic" cows significantly outperformed subjects of conventional breeding in all indicators: milk yield by 796-903 kg of milk, fat content by 0.27%, protein content by 0.09-0.06%, fat production by 59.4-63.8 kg, protein production by 33.9-34.8 kg, live weight by more than

At the Megrega farm, in terms of fat content and production, "genomic" individuals also significantly outperformed local peers, and in milk yield and protein content, the differences were unreliable. Genomic evaluation of animals and the involvement of "genomic" cows can contribute to the formation of better groups of mothers of future bulls, especially to solve the most urgent problem of increasing fat and protein milk.

Conclusion. In the conditions of large dairy breeding complexes with the technology of loose maintenance, it is advisable to use a system for placing groups of bull mothers in comfortable conditions in special rooms, including individual service.

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