Abstract：
Clostridium perfringens is one of the critical causative agents causing diarrhea in piglets, with significant economic losses to the pig industry. Under normal gut microbiota homeostasis and well-managed barns, diarrhea caused by C. perfringens could be controlled. Some reports show that probiotics, such as Bacillus subtilis, are beneficial in preventing necrotic enteritis (NE) in chickens, but few reports on piglets. Clostridium perfringens was found in the piglets\' diarrhea with intestinal microbiota dysbiosis in our survey. Bacillus subtilis G2B9-Q, which was isolated from the feces of healthy pigs, was found to have anti-Clostridium activity after screening. Clostridium perfringens was used to challenge mice by intraperitoneal injection for modeling to evaluate the anti-infective activity of cell-free supernatant (CFS) of B. subtilis G2B9-Q and different concentrations of B. subtilis G2B9-Q by oral administration. The results showed that G2B9-Q can mitigate intestinal lesions caused by C. perfringens infection, reduce inflammatory reactions, and modulate intestinal microbiota. The CFS of G2B9-Q can alleviate the pathological damage of intestinal tissues caused by C. perfringens infection, reduce the concentration of TNF-α and IL-10 in the sera of mice, as well as the relative expression levels of alpha toxin (CPA), perfringolysin O (PFO) toxin, IL-10, IL-22, and TNF-α in the jejunum and colon tissues, and alleviate the changes in gut microbiota structure caused by C. perfringens infection, which showed better therapeutic effects and indicated that the metabolites of G2B9-Q are essential mediators for their beneficial effects. Therefore, the CFS of G2B9-Q could potentially replace antibiotics in treating C. perfringens infection.
摘要：
产气荚膜梭菌是导致仔猪腹泻的关键病原体之一，给养猪业带来重大的经济损失。在正常的肠道微生物群稳态和管理良好的谷仓下，产气荚膜梭菌引起的腹泻是可以控制的。一些报告显示益生菌，如枯草芽孢杆菌，有利于预防鸡的坏死性肠炎（NE），但是关于仔猪的报道很少.在我们的调查中，在具有肠道微生物群失调的仔猪腹泻中发现了产气荚膜梭菌。枯草芽孢杆菌G2B9-Q,从健康猪的粪便中分离出来，筛选后发现具有抗梭菌活性。用产气荚膜梭状芽胞杆菌通过腹膜内注射攻击小鼠进行建模,评价口服枯草芽孢杆菌G2B9-Q和不同浓度枯草芽孢杆菌G2B9-Q的无细胞上清液(CFS)的抗感染活性。结果表明，G2B9-Q可以减轻产气荚膜梭菌感染引起的肠道病变，减少炎症反应，并调节肠道微生物群。G2B9-Q的CFS可以减轻产气荚膜梭菌感染引起的肠组织病理损伤,降低小鼠血清中TNF-α和IL-10的浓度，以及α毒素（CPA）的相对表达水平，产气荚膜溶素O（PFO）毒素，空肠和结肠组织中的IL-10，IL-22和TNF-α，缓解产气荚膜梭菌感染引起的肠道菌群结构变化，显示出更好的治疗效果，并表明G2B9-Q的代谢产物是其有益作用的必需介质。因此,G2B9-Q的CFS有可能替代抗生素治疗产气荚膜梭菌感染.
