Microbiome and its association with nutrient metabolism in farm animal nutrition

Abstract

This article shows the effect of amino acid preparations on metabolism, nutrient digestibility, and calf development. Essential amino acid mixes in different concentrations (per 1 kg of feed) were introduced into the diet of calves from 9 to 18 months of age: I experimental group - 2 g of lysine + 2 g of methionine + 3 g of threonine + 1 g of tryptophan, II experimental group - 3 g of lysine + 3 g of methionine + 4 g threonine+2 g tryptophan. Calves were calculated on pure amino acids, in % of feed dry matter (per head per day). In calves of the II experimental group there was a significant increase in live weight by 11.7 % (p≤0.05) due to better utilisation of bacterial nitrogen by 8.3 % (p≤0.05), amino acids in duodenum by 3.46 % (p≤0.05) than in the I experimental group and by 8.83 % (p≤0.05) than in the control group. The growth rate of tissues and their protein composition changed with the growth of animals. The obtained data indicate the positive effect of a mixture of amino acids with a higher concentration in the diet of growing animals due to the enhancement of protein biosynthesis processes in muscle tissue. Thus, for improvement of intestinal microbiota, metabolism, digestive processes, and maintenance of calf health, the most comfortable concentration of amino acids was the ratio of 3 g lysine+3 g methionine+4 g threonine+2 g tryptophan. The higher the level of essential amino acids in the feed composition, the more they increase the digestibility of nitrogenous substances in the gastrointestinal tract.