体外发酵法评估呼伦贝尔羊瘤胃对过瘤胃蛋氨酸的生物利用率及过瘤胃蛋氨酸对瘤胃微生物的影响  

Evaluation for bioavailability of rumen protected methionine and its effects on rumen microorganisms in Hulun Buir sheep by in vitro fermentation

作　　者：罗志斌 欧慧敏 李建中[2] 谭支良[1] 焦金真[1] LUO Zhibin;OU Huimin;LI Jianzhong;TAN Zhiliang;JIAO Jinzhen(Institute of Subtropical Agriculture,Chinese Academy of Sciences/Key Laboratory of Agro-ecological Processes in Subtropical Region/National Engineering Laboratory for Poultry Breeding Pollution Control and Resource Technology/Hunan Key Laboratory of Animal Nutritional Physiology and Metabolic Process,Changsha 410125,China;College of Life Sciences,Hunan Normal University/Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation,Changsha 410081,China)

机构地区：[1]中国科学院亚热带农业生态研究所/亚热带农业生态过程重点实验室/畜禽养殖污染控制与资源化技术国家工程实验室/湖南省动物营养生理与代谢过程重点实验室,湖南长沙410125 [2]湖南师范大学生命科学学院/动物肠道功能湖南省重点实验室,湖南长沙410081

出　　处：《江苏农业学报》2024年第5期874-880,共7页Jiangsu Journal of Agricultural Sciences

基　　金：中国科学院国际伙伴计划项目(161343KYSB20200015)。

摘　　要：为了探究呼伦贝尔羊瘤胃体外发酵体系对过瘤胃蛋氨酸(RPMet,由玉米淀粉和棕榈油包被)的生物利用率及过瘤胃蛋氨酸对瘤胃微生物类群的影响,取4只装有瘘管的雌性呼伦贝尔羊的瘤胃液进行体外发酵试验,在发酵起始阶段与发酵后2 h、4 h、6 h、8 h、12 h、24 h测定发酵体系中的RPMet降解率。每个发酵时间节点设置5个平行处理,在以上7个时间节点取发酵液并进行16S rDNA测序分析。结果表明,在体外发酵体系中,RPMet在发酵后8 h的降解率小于30.0%,说明该产品的包被效果较好。测序结果显示,发酵24 h后的Simpson指数显著低于发酵12 h后的Simpson指数(P<0.05)。主坐标分析(PCoA)能够显示物种的β-多样性,本研究结果显示,各时间点的聚类结果皆存在显著差异(P<0.05)。拟杆菌门、瘤胃球菌属、普雷沃氏菌属菌的相对丰度在发酵后8 h内显著上升,发酵12 h后显著下降(P<0.05)。厚壁菌门、广古菌门、甲烷杆菌属、解琥珀酸菌属、颤螺菌属菌的相对丰度在发酵后12 h内显著下降,之后显著上升(P<0.05)。综上所述,研究中所用的RPMet的包被效果较好,且发酵前期主要是普雷沃氏菌属、瘤胃球菌属微生物降解玉米淀粉包被层,而RPMet的过度降解显著提高了甲烷杆菌属微生物的相对丰度。The purpose of this study was to investigate the bioavailability of rumen-protected methionine(RPMet,coated with corn starch and palm oil)in the rumen in vitro fermentation system of Hulun Buir sheep and the effects of rumen-protected methionine on rumen microbial groups.The rumen fluids of four female Hulun Buir sheep with fistulas were taken for in vitro fermentation test.The degradation rate of RPMet in the fermentation system was determined at the initial stage of fermentation and 2 h,4 h,6 h,8 h,12 h and 24 h after fermentation.Five parallel treatments were set up at each fermentation time node,and the fermentation broth was taken at the above seven time nodes for 16S rDNA sequencing analysis.The results showed that the degradation rate of RPMet was less than 30.0%at 8 h after fermentation in the in vitro fermentation system,indicating that the coating effect of the product was good.The sequencing results showed that the Simpson index at 24 h after fermentation was significantly lower than that at 12 h after fermentation(P<0.05).Principal coordinate analysis(PCoA)could show theβ-diversity of species.The results of this study showed that there were significant differences in the clustering results at each time point(P<0.05).The relative abundance of Bacteroidetes,Ruminococcus and Prevotella increased significantly within 8 h after fermentation,and decreased significantly after 12 h of fermentation(P<0.05).The relative abundance of Firmicutes,Euryarchaeota,Methanobrevibacter,Succiniclasticum and Oscillibacter decreased significantly within 12 h after fermentation,and then increased significantly(P<0.05).In summary,the coating effect of the RPMet product is good.The Prevotella and Ruminococcus act as main genera to degrade the coating layer of corn starch during the early fermentation period,while excessive degradation of RPMet significantly increase the abundance of Methanobrevibacter.

关 键 词：过瘤胃蛋氨酸 绵羊 体外发酵 16S rDNA 微生物 

分 类 号：S852.23[农业科学—基础兽医学]