Mickdam Elsayed, Khiaosa-Ard Ratchaneewan, Metzler-Zebeli Barbara U, Klevenhusen Fenja, Chizzola Remigius, Zebeli Qendrim
Institute of Animal Nutrition and Functional Plant Compounds, Department of Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria; Nutrition and Clinical Nutrition Department, Faculty of Veterinary Medicine, South Valley University, 83523 Qena, Egypt; Research Cluster "Animal Gut Health", Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria.
Institute of Animal Nutrition and Functional Plant Compounds, Department of Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria; Research Cluster "Animal Gut Health", Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria.
Anaerobe. 2016 Jun;39:4-13. doi: 10.1016/j.anaerobe.2016.02.002. Epub 2016 Feb 8.
Rumen microbiota have important metabolic functions for the host animal. This study aimed at characterizing changes in rumen microbial abundances and fermentation profiles using a severe subacute ruminal acidosis (SARA) in vitro model, and to evaluate a potential modulatory role of plant derived alkaloids (PDA), containing quaternary benzophenanthridine and protopine alkaloids, of which sanguinarine and chelerythrine were the major bioactive compounds. Induction of severe SARA strongly affected the rumen microbial composition and fermentation variables without suppressing the abundance of total bacteria. Protozoa and fungi were more sensitive to the low ruminal pH condition than bacteria. Induction of severe SARA clearly depressed degradation of fiber (P < 0.001), which came along with a decreased relative abundance of fibrolytic Ruminococcus albus and Fibrobacter succinogenes (P < 0.001). Under severe SARA conditions, the genus Prevotella, Lactobacillus group, Megasphaera elsdenii, and Entodinium spp. (P < 0.001) were more abundant, whereas Ruminobacter amylophilus was less abundant. SARA largely suppressed methane formation (-70%, P < 0.001), although total methanogenic 16S rRNA gene abundance was not affected. According to principal component analysis, Methanobrevibacter spp. correlated to methane concentration. Addition of PDA modulated ruminal fermentation under normal conditions such as enhanced (P < 0.05) concentration of total SCFA, propionate and valerate, and increased (P < 0.05) degradation of crude protein compared with the unsupplemented control diet. Our results indicate strong shifts in the microbial community during severe SARA compared to normal conditions. Supplementation of PDA positively modulates ruminal fermentation under normal ruminal pH conditions.
瘤胃微生物群对宿主动物具有重要的代谢功能。本研究旨在利用严重亚急性瘤胃酸中毒（SARA）体外模型表征瘤胃微生物丰度和发酵特征的变化，并评估含有季铵型苯并菲啶和原小檗碱生物碱（其中血根碱和白屈菜红碱为主要生物活性化合物）的植物源生物碱（PDA）的潜在调节作用。严重SARA的诱导强烈影响瘤胃微生物组成和发酵变量，但不抑制总细菌的丰度。原生动物和真菌比细菌对低瘤胃pH条件更敏感。严重SARA的诱导明显抑制了纤维降解（P<0.001），同时纤维分解菌白色瘤胃球菌和琥珀酸纤维杆菌的相对丰度降低（P<0.001）。在严重SARA条件下，普雷沃氏菌属、乳酸杆菌属、埃氏巨球型菌和内毛虫属（P<0.001）更为丰富，而嗜淀粉瘤胃杆菌则较少。SARA在很大程度上抑制了甲烷生成（-70%，P<0.001），尽管总产甲烷16S rRNA基因丰度未受影响。根据主成分分析，嗜甲基短杆菌属与甲烷浓度相关。与未添加PDA的对照日粮相比，添加PDA在正常条件下调节瘤胃发酵，如提高（P<0.05）总挥发性脂肪酸、丙酸和戊酸浓度，并增加（P<0.05）粗蛋白降解。我们的结果表明，与正常条件相比，严重SARA期间微生物群落发生了强烈变化。在正常瘤胃pH条件下，添加PDA可对瘤胃发酵产生积极调节作用。
