THE FACTOR’S DEPENDENCE VARIABILITY OF THE LEVEL OF COW’S PRODUCTIVITY FROM LACTATION

Studies have shown that the correlation between milk productivity indicators fluctuates widely due to breed differences as well as external conditions (feeding, keeping, care). This analysis makes it possible to objectively determine the breed characteristics of productivity development and their variability. The existence of a positive correlation between these characteristics and milk yield will make it possible to ensure an effective breeding through the selection of animals by their productivity indicators. The high and direct correlation was determined between lactation duration and milk yield, while the average and direct correlation was between lactation duration, milk fat content and milk protein content. The inverse and low correlation was determined between milk fat content, while the direct and low correlation was between milk protein content, indicating the impact of other factors, such as heredity, level of feeding and the diet composition, on these characteristics.