乙醇梭菌蛋白对黄羽肉鸡生长性能、免疫功能和肠道健康的影响

Effects of Clostridium autoethanogenum Protein on Growth Performance,Immune Function and Intestinal Health of Yellow-Feathered Broilers

本试验旨在通过对生长性能、血浆和肠道免疫指标、肝脏生化指标和肠道黏膜屏障基因表达等指标的监测,研究乙醇梭菌蛋白对黄羽肉鸡生长性能、免疫功能和肠道健康的影响,确定乙醇梭菌蛋白在黄羽肉鸡饲粮中的适宜添加量。试验采用单因子随机分组设计,选用1280只1日龄健康、发育良好的快速型麻黄鸡,按照体重一致原则随机分为7个组,每组6个重复,每个重复30只鸡(公母各占1/2)。7组肉鸡分别饲喂在基础饲粮中加入0(对照)、0.8%、1.6%、2.4%、3.2%、4.0%、8.0%乙醇梭菌蛋白的试验饲粮。试验期共56 d。结果显示:1)1~21日龄阶段,3.2%组体重和平均日增重显著高于对照组和0.8%组(P<0.05);3.2%和8.0%组料重比显著低于对照组(P<0.05)。1~56日龄,4.0%和8.0%组平均日增重显著高于对照组和0.8%组(P<0.05),4.0%和8.0%组料重比显著低于对照组和0.8%组(P<0.05)。2)乙醇梭菌蛋白对黄羽肉鸡21和56日龄各器官指数均无显著影响(P>0.05)。3)21日龄时,4.0%组肝脏总超氧化物歧化酶(T-SOD)活性显著高于对照组、0.8%和2.4%组(P<0.05)。4)21日龄时,对照组和4.0%组血浆白细胞介素-1β(IL-1β)含量显著高于0.8%组(P<0.05);1.6%、4.0%和8.0%组血浆中肿瘤坏死因子-α(TNF-α)含量显著低于对照组和2.4%组(P<0.05)。56日龄时,3.2%、4.0%和8.0%组血浆白细胞介素-6(IL-6)含量显著低于对照组和0.8%组(P<0.05)。5)21日龄时,1.6%、2.4%、3.2%、4.0%和8.0%组空肠黏膜中闭锁小带蛋白-1(ZO-1)mRNA相对表达量显著高于对照组和0.8%组(P<0.05);1.6%组空肠黏膜中闭合蛋白1(Claudin1)mRNA相对表达量显著高于对照组和0.8%组(P<0.05);2.4%、3.2%和8.0%组空肠黏膜中核因子E2相关因子2(Nrf2)mRNA相对表达量显著高于对照组和0.8%组(P<0.05)。6)乙醇梭菌蛋白显著影响黄羽肉鸡粗蛋白质代谢率(P<0.05),其中4.0%和8.0%组粗蛋白质代谢率显著高于对照组(P<0.05)。综合以上结果,乙醇梭菌蛋白对黄羽肉鸡的生长性能、免疫功能和肠道健康有提高和改善作用。黄羽肉鸡饲粮中乙醇梭菌蛋白的适宜添加量为1.6%~4.0%。

This experiment was conducted to investigate the effects of Clostridium autoethanogenum protein(CAP)on growth performance,immune function and intestinal health of yellow⁃feathered broilers by monitoring growth performance,plasma and intestinal immune indexes,liver biochemical indexes and intestinal mucosal barri⁃er gene expression,and to determine the appropriate supplemental level of CAP in diets of yellow⁃feathered broil⁃ers.The experiment used a single factor randomized design.A total of 1280 one⁃day⁃old yellow⁃feathered broilers were randomly divided into 7 groups with 6 replicates in each group and 30 chickens(half male and half female)in each replicate.Broilers in 7 groups were fed the basal diets added 0(control),0.8%,1.6%,2.4%,3.2%,4.0%,8.0%CAP,respectively.The experiment lasted for 56 days.Results showed as follows:1)body weight and aver⁃age daily gain at 1 to 21 days of age in 3.2%group were significantly higher than those in control group and 0.8%group(P<0.05);the feed/gain in 3.2%and 8.0%groups was significantly lower than that in control group(P<0.05).The average daily gain at 1 to 56 days of age in 4.0%and 8.0%groups was significantly higher than that in control group and 0.8%group(P<0.05),and the feed/gain in 4.0%and 8.0%groups was significantly lower than that in control group and 0.8%group(P<0.05).2)CAP had no significant effects on organ indexes of yellow⁃feathered broilers at 21 and 56 days of age(P>0.05).3)At 21 days of age,the activity of liver total superoxide dismutase(T⁃SOD)in 4.0%group was significantly higher than that in the control group,0.8%and 2.4%groups(P<0.05).4)The plasma interleukin⁃1β(IL⁃1β)content in control and 4.0%groups was significantly higher than that in 0.8%group(P<0.05);the content of plasma tumor necrosis factor⁃α(TNF⁃α)in the 1.6%,4.0%and 8.0%groups was significantly lower than that in the control and 2.4%groups(P<0.05).Dietary CAP significantly affected plasma interleukin⁃6(IL⁃6)content at 56 days of age(P<0.05),and the IL⁃6 content in 3.2%,4.0%and 8.0%groups was significantly lower than that in control and 0.8%groups(P<0.05).5)The relative expression level of zonula occludens protein⁃1(ZO⁃1)mRNA in 1.6%,2.4%,3.2%,4.0%and 8.0%groups was significantly higher than that in control and 0.8%groups(P<0.05).The relative expression level of Claudin1 mRNA in 1.6%group was significantly higher than that in control group and 0.8%group(P<0.05).The relative expression level of nuclear factor E2 related factor 2(Nrf2)mRNA in 2.4%,3.2%and 8.0%groups was significantly higher than that in control and 0.8%groups(P<0.05).6)Dietary CAP significantly affected the crude protein metabolic rate of yellow⁃feathered broilers(P<0.05),and the crude protein metabolic rate in 4.0%and 8.0%groups was signifi⁃cantly higher than that in the control group(P<0.05).These results indicate that CAP can improve the growth per⁃formance,immune function and intestinal health of yellow⁃feathered broilers.The optimal dietary supplemental lev⁃el of CAP for yellow⁃feathered broilers is 1.6%to 4.0%.