PHYSIOLOGICAL AND BIOCHEMICAL STATUS OF DAIRY COWS WHEN FEEDING THEM SILAGE PRESERVED WITH A NEW SILAGE LEAVEN

The results of the influence of feeding silage prepared using the probiotic preparation (leaven) Josiferm on the physiological and biochemical status of dairy cows are presented. The chemical composition and nutritional value of the green mass of corn, and hence in the control and experimental samples of silage, as well as the degree of preservation of nutrients in the silage mass were determined. The experiment was conducted on two groups of Simmental cows, analogues in terms of lactation and milk yield. The animals of the control group received 24 kg of silage prepared using traditional technology, and the experimental group received 23 kg of silage preserved using the Josiferm leaven. It was found that the losses of nutrients of green mass of corn during ensiling, namely dry matter, crude protein and carotene in control samples were respectively: 18.2; 12.3 and 37.6%, in the experimental samples – 5.6; 5.5 and 20.7%. Also, the ratio of lactic to acetic acids was determined in the samples, which in the control variant was 50.51 : 37.04 and in the experimental variant – 75.66 : 23.03. It was found that feeding cows with silage preserved with the probiotic preparation Joziferm had a corresponding effect on the level of some indicators of nitrogen metabolism in the rumen content. A significantly higher concentration of total nitrogen in the rumen content of cows of the experimental group was noted (p≤0.05), mainly due to protein nitrogen, the level of which was 12.9% higher than in the control. An inverse relationship was established between the level of amine nitrogen and the content of ammonia in the rumen fluid, as well as a significantly (p≤0.05) higher content of nitrogen of free amino acids. In the blood of cows of the experimental group, a tendency to increase the concentration of erythrocytes and the degree of their saturation with hemoglobin was noted, as well as a significant (p≤0.05) increase in the content of protein nitrogen in their blood serum. The concentration of urea in the blood of experimental cows was significantly (p≤0.05) lower than in the control. Also, in the blood of cows of the experimental group, a significant (p≤0.01) increase in the sum of volatile fatty acids (VFAs) was noted on the background of a decrease (p≤0.05) in the level of ketone bodies, which caused an increase in their ketogenic coefficient by 38.2%. The obtained data suggest that feeding silage prepared with a probiotic to a greater extent contributes to the activation of the processes of reductive amination of keto acids with the formation of free amino acids, than the use of silage without a preservative.