酵母提取物和复合酶对感染大肠杆菌断奶仔猪生长性能和免疫状态的影响

Effects of yeast extract and complex enzyme on growth performance and immune status of weaned piglets challenged with Escherichia coli

本研究比较了添加或不添加复合酶的酵母提取物日粮与抗生素日粮对感染大肠杆菌仔猪生长性能、免疫状态和肠道绒毛结构的变化。试验选择24 d断奶的仔猪360头,随机分为6组,每组60头猪。试验处理包括阴性对照组、阳性对照组(断奶后7 d进行大肠杆菌攻毒)、阳性对照+抗生素组、阳性对照+酵母提取物组、阳性对照+复合酶组以及阳性对照+酵母提取物+复合酶组。结果:与阳性对照组相比,抗生素组显著改善仔猪日增重、采食量和饲料效率(P<0.05)。攻毒后6 h,抗生素组血清尿素氮含量和TNF-α浓度较阳性对照组显著降低(P<0.05),而血小板数量显著提高(P<0.05)。攻毒48 h后,抗生素组和复合酶+酵母提取物组血清尿素氮水平显著低于阳性对照组(P<0.05)。攻毒96 h后,抗生素组较阳性对照组显著降低血清尿素氮浓度(P<0.05),显著提高十二指肠、空肠和回肠绒毛高度(P<0.05)。攻毒6 h后,酵母提取物组(加或不加复合酶)较无酵母提取物组显著降低了血清TNF-α浓度,显著提高了血清IL-10浓度(P<0.05)。结论:感染大肠杆菌断奶仔猪日粮添加酵母提取物对仔猪的影响与抗生素相似,即降低血清尿素氮、十二指肠和回肠绒毛萎缩以及下调血清促炎细胞因子浓度。

In this study,we compared the growth performance,immune status and intestinal villi structure of E.coli infected piglets with or without a yeast extract diet and an antibiotic diet.360 piglets weaned on 24 days were randomly divided into 6 treatment groups with 60 pigs in each group.The treatment included:negative control group,positive control group(e.coli challenge 7 days after weaning),positive control+antibiotic group,positive control+yeast extract group,positive control+complex enzyme group and positive control+yeast extract+complex enzyme group.Results:compared with the positive control group,the antibiotic group significantly improved the daily gain,feed intake and feed efficiency of piglets(P<0.05).At 6 h after challenge,the serum urea nitrogen and TNF-αin concentration in the antibiotic group were significantly lower than those in the positive control group(P<0.05),while the platelet count was significantly higher(P<0.05).After 48 h of challenge,the serum urea nitrogen level in the antibiotic group and the complex enzyme+yeast extract group was significantly lower than that in the positive control group(P<0.05).At 96 h after challenge,the concentration of serum urea nitrogen in the antibiotic group was significantly lower than that in the positive control group(P<0.05),and the height of villi in the duodenum,jejunum and ileum was significantly increased(P<0.05).After 6 h of challenge,the concentration of serum TNF-αin the yeast extract group(with or without complex enzyme)significantly decreased and the concentration of serum il-10 significantly increased compared with the group without yeast extract(P<0.05).Conclusion:the effect of yeast extract on the diet of weaned piglets infected with E.coli was similar to that of antibiotics,that is,reducing serum urea nitrogen,reducing duodenal and ileum villi atrophy,and down-regulating serum proinflammatory cytokine concentration.