PDF(Pubmed)
Abstract：
The experiment was conducted to investigate the potential effects of steviol glycosides on growth performance, rumen fermentation processes, and microbial diversity in Hu sheep. A single-factor design was used for the trial. Twenty healthy weaned Hu lambs, possessing comparable body weights averaging 18.31 ± 1.24 kg, were randomly allocated into two distinct groups: the control group (CON) and the experimental group (STE), with each comprising 10 lambs. The CON was fed the basal diet, and the STE was supplemented with 0.07% steviol glycosides based on the basal diet. During the experimental period, variations in body weight and feed intake were closely monitored and recorded. After feeding for 90 d, blood was collected to determine blood biochemical indices, and rumen fluid samples were gathered for an in-depth analysis of rumen fermentation parameters and microbial diversity. The outcomes revealed no statistically significant differences in growth performance or serum biochemical indices between the two groups (p > 0.05). Rumen pH in STE and CON was within the normal range. The rumen ammonia nitrogen (NH3-N) and acetic acid (AA) content of STE decreased significantly compared with CON (p < 0.05). No significant variations were observed in the levels of other volatile fatty acids (VFAs) between the two groups (p > 0.05). The rumen microbial OTUs count, as well as the Shannon, Simpson, Chao1, and Ace indices, were notably lower in the STE group compared to the CON group (p < 0.05). Additionally, at the phylum level, the relative abundance of Firmicutes, Bacteroidetes, and Proteobacteria collectively accounted for over 97% of the total phylum composition. In comparison to the CON group, the STE group exhibited an increase in the relative abundance of Proteobacteria (p < 0.05), accompanied by a significant reduction in the relative abundance of Patescibacteria and Desulfobacteria (p < 0.05). At the genus level, there was a notable increase in the relative abundance of Prevotella_7 and Succinivibrionaceae_UCG_001 in the STE group, whereas the relative abundance of Rikenellaceae_RC9_gut_group significantly decreased (p < 0.05). According to the correlation analysis between rumen microflora and VFAs, the relative abundance of Succinivibrionaceae_UCG_001 displayed a significant negative correlation with AA (p < 0.05), whereas Lactobacillus exhibited a notable positive correlation with isobutyric acid (IBA) (p < 0.05). In summary, steviol glycosides had no significant effect on the production performance and blood biochemical indexes of Hu sheep. Steviol glycosides can improve rumen fermentation parameters and rumen microflora structure of Hu sheep and have a certain effect on rumen microbial diversity and composition.
摘要：
本试验旨在研究甜菊醇苷对生长性能的潜在影响。瘤胃发酵过程，湖羊的微生物多样性。试验采用单因素设计。二十只健康断奶的胡羔羊，具有相当的平均体重18.31±1.24公斤，随机分为两组:对照组(CON)和实验组(STE),每个包括10只羔羊。CON饲喂基础饮食，并且STE补充有基于基础饮食的0.07%的甜菊醇糖苷。在实验期间,密切监测和记录体重和采食量的变化.饲喂90d后，收集血液以确定血液生化指标，收集瘤胃液样品，对瘤胃发酵参数和微生物多样性进行深入分析。结果显示，两组之间的生长性能或血清生化指标差异无统计学意义（p>0.05）。STE和CON中的瘤胃pH在正常范围内。瘤胃氨氮(NH3-N)和乙酸(AA)含量的STE较CON明显下降(p<0.05)。两组间其他挥发性脂肪酸(VFA)水平无显著差异(p>0.05)。瘤胃微生物OTUs计数，以及香农，辛普森,Chao1和Ace指数，与CON组相比，STE组明显更低(p<0.05)。此外,在门的水平，Firmicutes的相对丰度，拟杆菌,和变形杆菌共同占总门组成的97％以上。与CON组相比，STE组显示变形杆菌的相对丰度增加（p<0.05），伴随着芽孢杆菌和脱硫杆菌的相对丰度显着降低（p<0.05）。在属一级，在STE组中，Prevotella_7和丁二弧菌科_UCG_001的相对丰度显着增加，Rikenellaceae_RC9_gut_组的相对丰度显着降低（p<0.05）。根据瘤胃微生物区系与VFA的相关性分析,丁烟菌科UCG001的相对丰度与AA呈显著负相关(p<0.05),而乳酸菌与异丁酸(IBA)呈显著正相关(p<0.05)。总之,甜菊醇苷对湖羊生产性能和血液生化指标无显著影响。甜菊醇苷可以改良湖羊瘤胃发酵参数和瘤胃微生物区系构造，对瘤胃微生物多样性和构成有必定影响。
