Comparison of sires in terms of milk productivity of daughters in “Tselinnoe” LLC, Republic of Khakassia

Relevance . Due to the diversity of herd origins and natural and climatic conditions, as well as animal husbandry technologies, regular evaluation of genealogical lines and testing of breeding bulls for the quality of their offspring is necessary in order to conduct selection with a guarantee of the greatest effect. Methods . Research on the study of milk productivity of red-and-white cows depending on their linear affiliation and comparison of breeding bulls by the productivity of their daughters was conducted in 2024 at Tselinnoye LLC in the Republic of Khakassia. In first-calf cows, the milk yield for 305 days, the fat and protein content in milk, the amount of milk fat and protein, live weight and milk coefficient were taken into account. Results . In the interline comparison of the milk productivity indices of first-calf heifers, the best in terms of milk yield were the descendants of the line Vis Back Ideal 1013415, exceeding their peers from the line Reflection Sovering 198998 in milk yield by 199.53 kg (3.27%) (р > 0.999), live weight by 4.59 kg (0.86%) (р > 0.95), milk coefficient by 28.15 kg (2.46%) (р > 0.999). The highest milk yield among the descendants of this line was demonstrated by the daughters of the bull-producer Madman 4719 (6433–4.14–266.3–3.28–211.0). The lowest milk yield was observed in the daughters of Madrid 13509 of the Reflection Sovering 198998 line (5957–4.14–246.8–3.27–194.9). In the Reflection Sovering 198998 line, the best daughters in terms of productivity were the bulls Talant 4117 and Speaker 4401, however, their descendants are characterized by the lowest live weight — 507–512 kg. The data obtained during the research will help livestock specialists to conduct successful selection for the creation of highly productive herds of dairy cattle.