IGESTIBILITY OF NUTRIENTS AND ENERGY SUPPLY OF ANIMALS UNDER THE INFLUENCE OF UNIFORMITY OF MIXING FEED

The article presents data from studies of the influence of the factor of uneven mixing of the feed mixture (corn silage, alfalfa hay and compound feed) on the apparent digestibility of nutrients throughout the gastrointestinal tract of young cattle (9 heifers of the Ukrainian red-motley breed). The studies used a method of modeling the consumption of unevenly mixed rations by animals, where 25 % of the ration consisted of high-energy components of the mixture in the second experiment, and feeds with a low energy concentration in the third. It was found that when consuming a low-concentrate feed mixture with an energy concentration in the diet of 8.9 MJ/kg dry matter and a crude protein concentration of 9.7 % with a mixing uniformity of 75 % compared to the control diet (100 % mixing uniformity), there were implausible changes in the consumption of nutrients by individual animals. Fluctuations in the apparent digestibility of nutrients throughout the gastrointestinal tract of young cattle ranged from 2 % to 6 % when consuming a feed mixture with a mixing uniformity of 75 %. On the high-nutrient diet, the digestibility of crude protein and crude fiber increased by 14% and 9 %, respectively. On the low-nutrient diet, there was a significant (p < 0.05) decrease in digestibility by 5 % for dry matter and organic matter and nitrogen-free extractives, and for crude protein (by 12 %), compared to the high-nutrient diet. The provision of animals with energy and protein significantly increased (p < 0.01) on the high-nutrient diet by 34.7 % and 11.5 %, respectively. Consumption of the low-nutrient diet had practically no effect on energy content. When feeding a feed mixture with a 75 % mixing uniformity on a low-nutrient diet, a significant increase in alkaline phosphatase activity was observed by 42 %, a high-nutrient diet significantly affected the increase in erythrocyte content by 7.9 %, while most hematological and biochemical blood parameters of heifers fluctuated within the physiological norm for animals of this age.