不同纤维来源饲粮和细胞壁降解酶对猪肠道微生物菌群多样性的影响

Gastrointestinal Microbial Flora Diversity in Pigs Fed Different Fibrous Diets with or without Cell Wall-Degrading Enzyme Supplementation

本试验旨在利用末端限制性片段长度多态性技术研究不同纤维来源饲粮和细胞壁降解酶对猪肠道微生物菌群多样性及其组成结构的影响。试验选用8头平均体重为(35.0±2.5)kg的"杜×长×大"三元杂交生长猪,统一安装回肠末端T型瘘管,随机分为4组,每组2个重复。试验分4期,每期每组猪按4×4拉丁方设计饲喂小麦麸、小麦麸加酶、大豆皮和大豆皮加酶4种试验饲粮之一。每期预试期15 d,正试期6 d。试验结果表明:1)大豆皮饲粮组猪回肠食糜微生物的多样性显著高于小麦麸饲粮组(P<0.05)。2)小麦麸饲粮组显著提高猪回肠食糜中普氏菌属(Prevotella)和乳酸杆菌属(Lactobacillus)的丰度(P<0.05),而大豆皮饲粮组则显著提高猪回肠食糜中瘤胃球菌属(Ruminococcus)及粪便中拟杆菌属(Bacteroides)、毛螺菌属(Lachnospira)的丰度(P<0.05)。3)添加细胞壁降解酶显著提高各饲粮组猪回肠食糜中Lachnospira、真细菌属(Eubacterium)及粪便中Lachnospira的丰度(P<0.05),但也同时降低了回肠食糜中Lactobacillus、Prevotella及粪便中Lactobacillus、Bacteroides和克雷伯氏菌属(Klebsiella)的丰度(P<0.05)。综上所述,纤维饲粮可显著提高猪肠道内非淀粉多糖降解菌的丰度,而细胞壁降解酶则可选择性改变肠道微生物菌群的多样性及其组成。

The microbial flora diversity and composition in pigs fed different fibrous diets with or without cell walldegrading enzyme supplementation were compared using terminal restriction fragment length polymorphism analysis technique.Eight growing castrated pigs fitted with a T-shaped cannula at the terminal ileum were randomly assigned to four diets,i.e.,wheat bran-based diet（WB）,enzyme-supplemented WB,soybean hull-based diet（SH）,and enzyme-supplemented SH,according to a 4 × 4 Latin square design.The experiment lasted for 6days after 15 days of adaptation in each period.The results showed as follows： 1） the microbial diversity of ileal digesta of pigs fed SH was significantly higher than that of pigs fed WB（P〈0.05）.2） The WB diet increased the abundances of Prevotella and Lactobacillus in ileal digesta（P〈0.05）,whereas the SH diet increased the abundances of Ruminococcus in ileal digesta and Bacteroides and Lachnospira in feces（P〈0.05）.3） Adding cell wall-degrading enzyme significantly increased the abundances of Lachnospira and Eubacterium in ileal digesta and Lachnospira in feces（P〈0.05）,whereas decreased the abundances of Lactobacillus,Prevotella in ileal digesta and Lactobacillus,Bacteroides and Klebsiella in feces（P〈0.05）.In conclusion,dietary fiber significantly increases the abundances of fiber-degrading bacteria,and cell wall-degrading enzyme supplementation selectively alters the microbial diversity and composition.