Н. С. Алтухова The studies are dedicated to the evaluation of changes in the genetic status of the pale dairy cattle population and its constituent breeds (Simmental and Red-and-White breed) on the main traits of milk productivity for the period from 1994 to 2017. Throughout the analysis period, a very moderate but positive trend was observed in the improvement of the genetic potential of these animal groups through the use of sires. The average annual genetic gain of the selected traits in the analysed breeding females varied from –1.06 to +18.64 kg for milk yield, from –0.001 to +0.004% for milk fat and protein content, from –0.02 to +0.82 kg for milk fat and milk protein; the selection index was from +0.10 to +0.36 economic units. This fact indicates a suboptimal system for evaluating the breeding value of animals in the population, for the formation of selection groups of sires and their use in the mass reproduction of breeding stock in the population.
Научная статья 
селекционный индекс