Dietary protein levels and amino acid supplementation patterns alter the composition and functions of colonic microbiota in pigs

• 作者: Bing Yu Daiwen Chen Gang Tian Jie Yu Jun He Junqiu Luo Ping Zheng Xiangbing Mao Yuheng Luo Yumei Zhao Zhiqing Huang
• 来源期刊: 动物营养:英文版
• 学科: 农学
• 关键词: Colonic microbiota Dietary protein level Essential amino acid PIG 16S high throughput sequencing
• 年，卷（期）: 2020,（2）
• 页码范围: 143-151
• 页数: 9页
• 分类号: S828.5

摘要

Different dietary nitrogen(N) patterns may have different effects on gut microbiota.To investigate the effects of different crude protein(CP) levels or essential amino acids(EAA) supplementation patterns on the structure and functions of colonic microbiota,42 barrows(25±0.39 kg) were randomly assigned to 7 dietary treatments including:diet 1,a high CP diet with balanced 10 EAA;diet 2,a medium CP diet with approximately 2% decreased CP level from diet 1 and balanced 10 EAA;diets 3,4,5,6 and 7,low CP diets with 4% decreased CP level from diet 1.Specifically,diet 3 was only balanced for Lys,Met,Thr and Trp;diets 4,5 and 6 were further supplemented with IIe,Val and IIe+Val on the basis of diet 3,respectively;and diet 7 was balanced for 10 EAA.Results over a 110-d trial showed that reducing the CP level by 2% or4% dramatically decreased N intake and excretion(P <0.05) in the presence of balanced 10 EAA,which was not observed when altering the EAA supplementation patterns in low CP diet(-4%).With balanced10 EAA,2% reduction in dietary CP significantly reduced Firmicutes-to-Bacteroidetes(F:B) ratio and significantly elevated the abundance of Prevotellaceae NK3 B31(P <0.05);whereas 4% reduction evidently increased the abundances of Proteobacteria,Succinivibrio and Lachnospiraceae XPB1014(P <0.05).Among the 5 low CP diets(-4%),supplementation with Ile,or Val+Ile,or balanced 10 EAA increased F:B ratio and the abundance of Proteobacteria.In addition,the predicted functions revealed that different CP levels and EAA balanced patterns dramatically altered the mRNA expression profiles of N-metabolizing genes,the "N and energy metabolism" pathways or the metabolism of some small substances,such as amino acids(AA) and vitamins.Our findings suggested that reducing the dietary CP levels by 2% to 4% with balancing 10 EAA,or only further supplementation with Ile or Val+Ile to a low protein diet(-4%) reduced the N contents entering the hindgut to various degrees,altered the abundances of N-metabolizing bacteria,and improved the abili