Evaluation of Yaroslavl cattle lines based on economically useful characteristics

The Yaroslavl cattle breed is known for high fat and protein content in milk, resistance to infectious diseases, adaptability to feeding and maintenance conditions in the central and northern zones of the European part of the Russian Federation. The Government has set a task to develop programs to improve dairy cattle breeds for their preservations and increasing competitiveness. Therefore, the goal was set to evaluate the productive characteristics and reproductive quali- ties of Yaroslavl cows of different lines bred in the Yaroslavl and Vologda regions. The research revealed that the Yaroslavl population is the most diverse in terms of the number of lineages. Cows of the Yaroslavl population outperform cows of the Vologda population in milk yield for 100 days of lactation and for 305 days of lactation for the last completed lactation by 515.6 and 1 804.2 kg, respectively. The cows of the Vologda region are the most dairy-rich, with a superiority in fat percentage over the Yaroslavl population in all lines from 0.35 to 0.58 %. Cows of the Yaroslavl population of the Volny 470 YAYA-4370 line had the earliest age of the first insemination, the first fruitful insemination and the first calving – 16.2 months, 17 months and 26.1 months, which is lower than that of the Vologda population by 5.8; 5.0 and 3.0 %, respectively, which is statistically significant. Animals of the Yaroslavl population have the highest live weight at birth and the last completed lactation along all lines except for the Sorcerer’s line 62 YAYA-1544. Cows of the Vologda region have the longest period of economic use, which ranges from 2.4 to 6.5 lactation. The research allows to improve genetic potential of the Yaroslavl cattle breed through the purpose breeding according to lines and through conservation of genetic diversity. The receiver results can be used to develop selection programs, what will contribute to further work with his valuable breed.