Effect of Protein Level in Diets Supplemented by Essential Amino Acids on Apparent Ileal Digestibility in Young Pigs

Abstract

AbstractIn the experiments on piglets aged 2.5–4.0 months with a T-shaped cannula at the terminal ileum, it was found that a decrease in the diet level of crude protein to 151 g/kg DM from 172 in control group, with additive of lys, thre and meth, does not have a negative effect on the fecal and apparent ileal digestibility of amino acids, crude protein and gross energy compared to the control. With a decrease in the level of feed protein to 134 g/kg DM, the ileal digestibility of lys decreased by 8.3 (P < 0.01)%, thr by 14.8 (P < 0.01), meth + cys by 7,3 (P < 0.05), leu by 13.6 (P < 0.01), lie by 6.6 (P < 0.05), val by 4.9 (P < 0.05), phe by 3.5, his by 7.3 (P < 0.05), arg by 6.4 (P < 0.05), CP by 5.9% and gross energy by 2.8% vs standard diet. Such a decrease in the digestibility of amino acids of this group can be explained by the fact that more grain components were introduced into the diet, which have lower digestibility coefficients compared to high-protein feeds. Reducing CP to 134 g/kg feed with the addition of limiting amino acids, reduced the ileal digestibility of essential amino acids vs standard diet due to the violation of the ratio between essential and nonessential amino acids in the feed. Thus, in order to achieve high productivity of growing pigs, rations should be adjusted in accordance with the norms of the need for essential amino acids, the ratio between them and their digestibility in the intestinal tract.KeywordsGrowing pigsProtein levels in dietEssential amino acidsIleal amino acid digestibility