Abstract
The influence of the composition of the diet on the productive indicators of cows, in particular on the chemical composition of milk, is analyzed. A reduction in the supply of succulent feed to 46.6% of the total energy nutrition and an increase in the proportion of concentrates (up to 53.4% of the exchange energy) for dairy cows were unacceptable. During the study, the level of milk productivity of black-andwhite cows increased very slightly – by 0.7 kg head /day. It is possible that in the first days of the change of the cow's diet, the total gross milk yield increases, but this period does not last long, and soon cows with acidosis and other metabolic disorders appear on the farm. The increase in the level of concentrated feed in the farm negatively affected the physico-chemical composition of milk, which became unsorted. A negative consequence of the change in the diet of cows was a deterioration in the quality of milk. Thus, the ratio of «fat – protein» has changed in the opposite direction, the urea content has increased (to 48.58–52.97 mg / 100 ml), the titrated acidity of milk has increased (to 19.49–21.04 °T) and the content of somatic cells in milk (to the level of 354.41–450.54 thousand / cm3) in cows of all lactations.