Optimizing the use of protein in the young cattle body

Abstract

The organization of complete feed rations for cattle meeting the needs of animals in energy, protein, amino acids, minerals and vitamins in terms of basic nutrients and biologically active substances represents the main condition to achieve the genetic potential of productivity. The purpose of the paper was to optimize the protein utilization in the body of young cattle by synchronizing the processes of fermentation of nitrogen-containing substances and carbohydrates in feed. Barothermal treatment of concentrated feed mixtures with high protein degradability and a high content of non-structural carbohydrates causes a more uniform fermentation of nutrients, intensification of microbial protein synthesis processes and an increase in the efficiency of energy use of carbohydrates and protein nitrogen by rumen microflora. This is evidenced by an increase in the number of ciliates by 4.4–8.1% and a decrease in the concentration of ammonia and volatile fatty acids in the rumen fluid by 5.2–9.2 % and 3.4–4.3 %, respectively. A decrease in nitrogen losses is indicated by a decrease in the content of urea in animals’ blood by 2.0–9.0%. Extrusion of concentrated feeds with high protein degradability and high content of non-structural carbohydrates improves animal productivity and feed efficiency. The average daily gain in live weight increases by 4.8-6.0% in the experimental group. As a result, feed consumption is reduced by 2.7-6.9%, while protein consumption is reduced by 2.6-5.7%.