Department of Animal Sciences, University of Illinois, Urbana, IL, USA.
Veterinary Diagnostic Laboratory, University of Illinois, Urbana, IL, USA.
J Anim Sci. 2024 Jan 3;102. doi: 10.1093/jas/skae105.
Frequent incidence of postweaning enterotoxigenic Escherichia coli (ETEC) diarrhea in the swine industry contributes to high mortality rates and associated economic losses. In this study, a combination of butyric, caprylic, and capric fatty acid monoglycerides was investigated to promote intestinal integrity and host defenses in weanling pigs infected with ETEC. A total of 160 pigs were allotted to treatment groups based on weight and sex. Throughout the 17-d study, three treatment groups were maintained: sham-inoculated pigs fed a control diet (uninfected control [UC], n = 40), ETEC-inoculated pigs fed the same control diet (infected control [IC], n = 60), and ETEC-inoculated pigs fed the control diet supplemented with monoglycerides included at 0.3% of the diet (infected supplemented [MG], n = 60). After a 7-d acclimation period, pigs were orally inoculated on each of three consecutive days with either 3 mL of a sham-control (saline) or live ETEC culture (3 × 109 colony-forming units/mL). The first day of inoculations was designated as 0 d postinoculation (DPI), and all study outcomes reference this time point. Fecal, tissue, and blood samples were collected from 48 individual pigs (UC, n = 12; IC, n = 18; MG, n = 18) on 5 and 10 DPI for analysis of dry matter (DM), bacterial enumeration, inflammatory markers, and intestinal permeability. ETEC-inoculated pigs in both the IC and MG groups exhibited clear signs of infection including lower (P < 0.05) gain:feed and fecal DM, indicative of excess water in the feces, and elevated (P < 0.05) rectal temperatures, total bacteria, total E. coli, and total F18 ETEC during the peak-infection period (5 DPI). Reduced (P < 0.05) expression of the occludin, tumor necrosis factor α, and vascular endothelial growth factor A genes was observed in both ETEC-inoculated groups at the 5 DPI time point. There were no meaningful differences between treatments for any of the outcomes measured at 10 DPI. Overall, all significant changes were the result of the ETEC infection, not monoglyceride supplementation.
断奶后肠产毒性大肠杆菌（ETEC）腹泻在养猪业中频繁发生，导致高死亡率和相关经济损失。在这项研究中，丁酸、辛酸和癸酸单甘油酯的组合被研究用于促进感染 ETEC 的断奶仔猪的肠道完整性和宿主防御。总共 160 头猪根据体重和性别分配到治疗组。在整个 17 天的研究过程中，维持了三组处理：假接种猪喂食对照饮食（未感染对照[UC]，n = 40）、ETEC 接种猪喂食相同对照饮食（感染对照[IC]，n = 60）和 ETEC 接种猪喂食对照饮食补充 0.3%的单甘油脂（感染补充[MG]，n = 60）。经过 7 天的适应期后，猪连续三天每天口服接种 3 mL 假对照（盐水）或活 ETEC 培养物（3×109 个菌落形成单位/mL）。接种的第一天被指定为接种后 0 天（DPI），所有研究结果均参考此时间点。在第 5 天和第 10 天，从 48 头单独的猪（UC，n = 12；IC，n = 18；MG，n = 18）中收集粪便、组织和血液样本，用于分析干物质（DM）、细菌计数、炎症标志物和肠道通透性。IC 和 MG 组中的 ETEC 接种猪表现出明显的感染迹象，包括较低的（P<0.05）增重：饲料和粪便 DM，表明粪便中含有过量的水，以及升高的（P<0.05）直肠温度、总细菌、总大肠杆菌和总 F18 ETEC 在感染高峰期（5 DPI）。在第 5 DPI 时间点，两组 ETEC 接种猪的紧密连接蛋白、肿瘤坏死因子-α和血管内皮生长因子 A 基因的表达均降低（P<0.05）。在第 10 DPI 时，对于测量的任何结果，处理之间均无明显差异。总体而言，所有显著变化都是 ETEC 感染的结果，而不是单甘油脂的补充。
