Li Siqi, Du Meiyu, Zhang Chongyu, Wang Yun, Lee Yunkyoung, Zhang Guiguo
College of Animal Sciences and Technology, Shandong Agricultural University, Taian, China.
Interdisciplinary Graduate Program in Advanced Convergence Technology and Science, Department of Food Science and Nutrition, Jeju National University, Jeju, South Korea.
Front Microbiol. 2022 Apr 25;13:824001. doi: 10.3389/fmicb.2022.824001. eCollection 2022.
The pelleted total mixed ration (PTMR) has a positive effect on the productivity of fattening lambs. However, whether the beneficial effects are underpinned by altering the rumen microbiota and metabolome that remain unclear. This study aimed to investigate correlations among growth performance, ruminal microbiota, and ruminal metabolome of lambs fed PTMR diet. A total of 100 crossbred (Dorper sheep × Fine-wool sheep) ram lambs at 55 days of age with similar body weight (BW) (13.2 ± 0.5 kg) were randomly allocated to 10 pens that were fed either PTMR (PTMR group) or unpelleted total mixed ration (UPTMR group) with the same dietary ingredients and nutritional contents. The average daily gain (ADG) and average daily feed intake (ADFI) were determined during the 62-day experimental period and ruminal pH, volatile fatty acid (VFA) concentrations, microbiota, and metabolome in the rumen of the lambs were examined at the end of the experiment. Compared to those of the UPTMR group, the PTMR group had greater ADFI ( = 0.002), ADG ( = 0.003), and feed efficiency (G/F) ( < 0.05). Similarly, feeding PTMR increased the concentration of total VFA (TVFA) and the molar proportion of propionate, but decreased the proportion of butyrate and acetate to propionate ratio in the rumen of lambs compared to that in lambs from the UPTMR group ( < 0.05). In addition, the PTMR group demonstrated lowered alpha-diversity of the ruminal microbiota and enhanced the relative abundance of ( < 0.05), ( < 0.05), and the abundance of ( = 0.064) in the rumen compared with those in the UPTMR group. Feeding lambs with PTMR significantly upregulated the metabolic pathways involving tryptophan, histidine, cysteine and methionine, β-alanine, tyrosine metabolisms, and steroid biosynthesis. Moreover, the abundance of the microbiota strongly correlated with the altered performance, ruminal VFA, metabolites, and metabolic pathways of lambs. Taken together, feeding PTMR shaped the ruminal microbiota of lambs with decreased diversity, while improving relative abundance of some specific microbes and upregulating certain growth-related metabolic pathways, which contributed to the augmented growth performance and G/F of fattening lambs. Thus, feeding PTMR to fattening lambs for superior production performance and G/F is recommended.
颗粒全混合日粮（PTMR）对育肥羔羊的生产性能有积极影响。然而，这些有益效果是否通过改变瘤胃微生物群和代谢组来支撑仍不清楚。本研究旨在调查饲喂PTMR日粮的羔羊生长性能、瘤胃微生物群和瘤胃代谢组之间的相关性。将100只55日龄、体重相似（BW）（13.2±0.5千克）的杂交（杜泊羊×细毛羊）公羔羊随机分配到10个栏中，分别饲喂PTMR（PTMR组）或非颗粒全混合日粮（UPTMR组），两组日粮成分和营养含量相同。在62天的试验期内测定平均日增重（ADG）和平均日采食量（ADFI），并在试验结束时检测羔羊瘤胃的pH值、挥发性脂肪酸（VFA）浓度、微生物群和代谢组。与UPTMR组相比，PTMR组的ADFI更高（P = 0.002）、ADG更高（P = 0.003）且饲料效率（G/F）更高（P < 0.05）。同样，与UPTMR组的羔羊相比，饲喂PTMR增加了羔羊瘤胃中总挥发性脂肪酸（TVFA）的浓度和丙酸的摩尔比例，但降低了丁酸比例以及乙酸与丙酸的比例（P < 0.05）。此外，与UPTMR组相比，PTMR组瘤胃微生物群的α多样性降低，瘤胃中[具体微生物名称1]的相对丰度增加（P < 0.05）、[具体微生物名称2]的相对丰度增加（P < 0.05）以及[具体微生物名称3]的丰度增加（P = 0.064）。给羔羊饲喂PTMR显著上调了涉及色氨酸、组氨酸、半胱氨酸和蛋氨酸、β-丙氨酸、酪氨酸代谢以及类固醇生物合成的代谢途径。此外，微生物群的丰度与羔羊性能改变、瘤胃VFA、代谢产物和代谢途径密切相关。综上所述，饲喂PTMR塑造了多样性降低的羔羊瘤胃微生物群，同时提高了一些特定微生物的相对丰度并上调了某些与生长相关的代谢途径，这有助于提高育肥羔羊的生长性能和G/F。因此，建议给育肥羔羊饲喂PTMR以获得更好的生产性能和G/F。
