WET CRUSHED MAIZE GRAIN IN DAIRY COW NUTRITION AND ITS EFFECT ON PHYSICAL AND CHEMICAL COMPOSITION OF MILK
The experiment was conducted in 2018 on the farm of the OOO “Partner”, Mikhaylovskiy District of the Altai Region; Simmental cows were involved. To carry out the experiments, four groups of ten cows were formed. The cows of the control group were fed the standard diet. The cows of the 1st trial group received 2.5 kg of wet crushed maize grain (WCMG) included in the standard diet (7.1% in terms of nutritional value). The comparable cows of the 2nd trial group were fed the standard diet and 3 kg of WCMG (8.5% in terms of nutritional value). The cows of the 3rd trial group - the standard diet and 3.5 kg of WCMG (10.1% in terms of nutritional value). Wet crushed maize grain was included in the standard diet of first-calf heifers during the first 100 days of lactation starting from the 2nd month of lactation for 60 days. In terms of the average daily milk yield, the cows of the 1st trial group had the highest milk yield; it exceeded the control by 20.9% (p < 0.01), and the cows of the 2nd and 3rd trial groups exceeded by 13.2% and 14.6% (p < 0.05), respectively. The content of dry matter in the milk of cows of the 1st, 2nd and 3rd trial groups increased by 0.3%, 0.6% (p < 0.05) and 0.1%, respectively. In terms of protein content in milk, the cows of the trial groups tended to exceed the control by 0.1% and 0.3%, respectively, and in terms of casein content - by 0.1% and 0.2%. Urea content in the milk of the control group was higher than in the milk of the cows of the 1st, 2nd and 3rd trial groups by 22.8%, 20.0% and 19.0%, respectively; in terms of density, it yielded to the milk obtained from the trial cows from 0.05% to 0.12%. In terms of somatic cell concentration in milk, the cows of 1st, 2nd and 3rd trial groups had increasing trend as compared to the control by 25.1%, 34.7% and 67.2%, respectively.