CHEMICAL COMPOSITION OF COW MILK AS AN INDICATOR OF NUTRITIONAL CONTENT

Abstract

Feeding dairy cows with a diet containing raw protein of 10.7% of dry matter, led to an increase in urea in cow milk to 45.9 mg/ml, changes in the fat: protein ratio in milk within 0.8:1, decreased resistance of cows and as a consequence an increase in somatic cells in milk to 302.3 thousand/cm³. The adjusted diet of feeding cows with the content of crude protein at the level of 9.9% of dry matter had a beneficial effect on the quantitative and qualitative indices of milk productivity of black-motley breed cows in the conditions of JSC "Zarya". Thus, urea concentration in milk decreased to 32,3 mg/ml, milk fat: protein ratio improved by 1,06:1, cow’s metabolism normalized, the resistance of animals increased and the number of somatic cells in milk decreased to 164,2 thousand/cm3. It is noted that cows at different lactation stages respond differently to feed changes. Cows lactating for more than 201 days, i.e. in the final stage of lactation, were more responsive to ration changes. The groups of cows receiving 1821 grams of crude protein per day in the diet had better quantitative and qualitative milk production indices in contrast to the groups receiving 2163 grams of crude protein with the diet.