文献类型： 外文期刊

作者： Zhang, Zhenbin ¹ ; Sun, Yiquan ¹ ; Zhong, Xinhuang ¹ ; Zhu, Jun ¹ ; Yang, Sihan ¹ ; Gu, Yalan ¹ ; Yu, Xiang ¹ ; Lu, Yue ¹ ; Lu, Zhiqi ¹ ; Sun, Xuezhao ⁴ ; Wang, Mengzhi ¹ ;

作者机构： 1.Yangzhou Univ, Coll Anim Sci & Technol, Lab Metab Manipulat Herbivorous Anim Nutr, Yangzhou 225009, Peoples R China

2.Xinjiang Acad Agr & Reclamat Sci, State Key Lab Sheep Genet Improvement & Hlth Prod, Shihezi 832000, Xinjiang, Peoples R China

3.Shanghai Frontan Anim Hlth Co Ltd, Shanghai 201502, Peoples R China

4.AgResearch, Grasslands Res Ctr, Palmerston North 4410, New Zealand

关键词： Soluble protein; Low -protein diet; Nitrogen metabolism; Reactive nitrogen; Fecal microbiota and metabolome; Energy and nitrogen utilization ef ficiency

期刊名称：ANIMAL NUTRITION （ 影响因子：6.1； 五年影响因子：6.5 ）

ISSN： 2405-6383

年卷期： 2024 年 18 卷

页码：

收录情况： SCI

摘要： Dietary nutrient manipulation (e.g. protein fractions) could lower the environmental footprints of ruminants, especially reactive nitrogen (N). This study investigated the impacts of dietary soluble protein (SP) levels with decreased crude protein (CP) on intestinal N absorption, hindgut N metabolism, fecal microbiota and metabolites, and their linkage with N metabolism phenotype. Thirty-two male Hu sheep, with an age of six months and an initial BW of 40.37 +/- 1.18 kg, were randomly assigned to four dietary groups. The control diet (CON), aligning with NRC standards, maintained a CP content of 16.7% on a dry matter basis. Conversely, the experimental diets (LPA, LPB, and LPC) featured a 10% reduction in CP compared with CON, accompanied by SP adjustments to 21.2%, 25.9%, and 29.4% of CP, respectively. Our results showed that low-protein diets led to significant reductions in the concentrations of plasma creatinine, ammonia, urea N, and fecal total short-chain fatty acids (SCFA) (P < 0.05). Notably, LPB and LPC exhibited increased total SCFA and propionate concentrations compared with LPA (P < 0.05). The enrichment of the Prevotella genus in fecal microbiota associated with energy metabolism and amino acid (AA) biosynthesis pathways was evident with SP levels in low-protein diets of approximately 25% to 30%. Moreover, LPB and LPC diets demonstrated a decrease in fecal NH4+-N and NO2--N contents as well as urease activity, compared with CON (P < 0.05). Concomitantly, reductions in fecal glutamic acid dehydrogenase gene (gdh), nitrite reductase gene (nirS), and nitric oxide reductase gene (norB) abundances were observed (P < 0.05), pointing towards a potential reduction in reactive N production at the source. Of significance, the up-regulation of mRNA abundance of AA and peptide transporters in the small intestine (duodenum, jejunum, and ileum) and the elevated concentration of plasma AA (e.g. arginine, methionine, aspartate, glutamate, etc.) underscored the enhancement of N absorption and N efficiency. In summary, a 10% reduction in CP, coupled with an SP level of approximately 25% to 30%, demonstrated the potential to curtail reactive N emissions through fecal Prevotella enrichment and improve intestinal energy and N utilization efficiency. (c) 2024 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).