Biological completeness of protein and its role in farm animals feeding

Abstract

Purpose. To study the biological completeness of the feed protein, including green mass of cereal and leguminous fodder crops. To find out the role of their aminoacid composition for farm animals feeding. Methods. Sampling was carried out in accordance with State Standard of Ukraine ISO 6497:2005, determination of the content of moisture and other volatile substances – State Standard of Ukraine ISO 6496:2005, nitrogen and crude protein – State Standard of Ukraine 7169:2010. The amino acid composition of protein was determined on the AAA500 ion-exchange automatic analyzer. Results. Cereal grain proteins are characterized by a relatively low content of lysine, threonine, and corn grain – of tryptophan. The richest source of essential aminoacids among plant feeds is soybean meal, which contains, on average, 43% of protein. The complex use of sunflower and rapeseed meal maximally balances the protein nutrition of animals and the. But this raw material should be checked for protein and non-protein nitrogen content to confirm its natural origin. For ruminants, the green mass of cereal crops is a valuable feed, because the crude protein content in it reaches 12% in the tillering phase, but decreases two times in the earing phase. In the green mass of legumes, alfalfa and chickweed, the content of crude protein in the branching phase is at the level of 27-29% in terms of absolutely dry matter, and in the flowering phase –15-17%. In terms of the content of individual aminoacids, the green mass of leguminous crops exceeds the green mass of cereal fodder crops by 1.5-2 times. Conclusions. The content of lysine in triticale and rye grains is the highest – 3.6%, while in wheat – only 2.8%. An important condition in solving the problem of animal protein nutrition is its multicomponent nature, which ensures a better balance in terms of aminoacids. In terms of the content of individual aminoacids, the green mass of leguminous crops exceeds the green mass of cereal fodder crops by 1.5-2 times, while the green mass of cereal crops is characterized by a lower protein content compared to legumes.