College of Animal Science and Technology, Northwest Agriculture & Forestry University, Xianyang, 712100, Shaanxi, China.
BMC Vet Res. 2023 Feb 2;19(1):32. doi: 10.1186/s12917-023-03592-6.
Higher dietary energy is often used to achieve better animal performance in mutton sheep production. Notably, changing the diet formula affects rumen fermentation and the microbiota of ruminants. In this study, we investigated the effect of dietary energy on rumen fermentation and ruminal microbiota in fattening sheep. Fifteen 2-month-old white-headed Suffolk sheep (♂) × Hu sheep (♀) crossbred lambs were randomly divided into three treatments based on the dietary energy of the feeds fed: 8.67 MJ/kg (Low energy (LE); n = 5), 10.38 MJ/kg (standard energy (CON); n = 5), and 12.31 MJ/kg (high energy (HE); n = 5) groups. After 70 days of feeding, sheep were slaughtered and the ruminal fluids were collected and analyzed to determine fermentation parameters. Microbiota was determined using metagenomics sequencing. Notably, the microbial cell protein (MCP) and butyric acid concentrations were significantly high in the HE group. Metagenomic sequencing revealed that ACE and Chao indexes of the HE group were significantly decreased. Four genera among the major classified taxa across all the kingdoms differed in relative abundance in the three dietary energy levels. The relative abundances of Prevotella_brevis, Succiniclasticum_ruminis, Prevotellace-ae_bacterium, and Lachnospiraceae_bacterium were significantly correlated with rumen fermentation. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis further revealed that a high-energy diet increased lipid metabolism of microbiota. The Carbohydrate Active enzymes (CAZy) gene, which participates in energy metabolism, was upregulated, while genes regulating plant cell wall degradation were downregulated in the HE group. These results suggest that a high-energy diet had minimal influence on the rumen fermentation pattern but altered the composition of the rumen microbiota, enhancing microbial lipid metabolism and limiting crude fiber metabolism. The findings of this study provide scientific evidence of the effect of dietary energy on ruminant fermentation and fattening sheep production.
更高的膳食能量通常用于提高羊肉生产中动物的性能。值得注意的是，改变饲料配方会影响反刍动物的瘤胃发酵和微生物区系。本研究旨在探讨饲粮能量对育肥绵羊瘤胃发酵和瘤胃微生物区系的影响。将 15 只 2 月龄白头萨福克羊（♂）×湖羊（♀）杂交羔羊随机分为 3 个处理组，根据饲料的饲粮能量水平分别饲喂：8.67 MJ/kg（低能量（LE）组，n = 5）、10.38 MJ/kg（标准能量（CON）组，n = 5）和 12.31 MJ/kg（高能量（HE）组，n = 5）。经过 70 天的饲养，对绵羊进行屠宰并采集瘤胃液进行发酵参数分析。使用宏基因组测序法测定微生物区系。结果表明，HE 组的微生物细胞蛋白（MCP）和丁酸浓度显著升高。宏基因组测序结果显示，HE 组的 ACE 和 Chao 指数显著降低。在所有分类群中，有 4 个属的相对丰度在 3 种饲粮能量水平下存在差异。在 3 种饲粮能量水平下，Prevotella_brevis、Succiniclasticum_ruminis、Prevotellaceae_bacterium 和 Lachnospiraceae_bacterium 的相对丰度与瘤胃发酵显著相关。京都基因与基因组百科全书（KEGG）途径富集分析进一步表明，高能饮食增加了微生物的脂质代谢。碳水化合物活性酶（CAZy）基因参与能量代谢，在 HE 组中上调，而调节植物细胞壁降解的基因在 HE 组中下调。这些结果表明，高能饮食对瘤胃发酵模式的影响较小，但改变了瘤胃微生物区系的组成，增强了微生物的脂质代谢，限制了粗饲料的代谢。本研究结果为饲粮能量对反刍动物发酵和育肥绵羊生产的影响提供了科学依据。
