THE INFLUENCE OF BULLS’ BREEDING VALUE ON THE MILK PRODUCTIVITY OF THEIR DAUGHTERS IN SERF «OLEKSANDRIVSKE»

The article presents a qualitative characteristic of breeding bulls used in the herd of the breeding farm SERF “Oleksandrivske” of Vinnytsia region. The distribution of bulls by breeding index and class of breeding value in populations of Ukrainian Black-and-White and Red-and-White Dairy breeds is analyzed, and an increase in the proportion of bulls with high breeding indices over the past five years is noted. The milk productivity of daughters of bulls evaluated by different methods (MACE and PTA) was studied, and high indicators of milk yield and milk fat in the daughters of bulls evaluated by these methods were revealed. It was established that bulls with high breeding indices predominantly had daughters with high milk yields, but a decrease in fat content in their milk was observed. Correlation analysis revealed a low positive relationship between the milk yield of mothers and the breeding index of sons, a direct significant relationship between the breeding indices of bulls and the milk yield of their daughters, as well as a negative significant relationship between the breeding indices of bulls and the fat content in the milk of their daughters. A reverse significant relationship between milk yield and fat content in the milk of daughters was also established, which complicates simultaneous selection for these traits. High coefficients of variation in milk yield and milk fat in both populations justify the expediency of further breeding work in this direction.