辣椒碱对818肉鸡生长性能、血浆生化指标以及肠道健康的影响

Effects of Capsaicin on Growth Performance,Plasma Biochemical Indices and Intestine Health of 818 Chickens

本试验旨在研究辣椒碱对818肉鸡生长性能、血浆生化指标、肠道消化酶活性、肠道营养物质转运载体相关基因mRNA表达量和盲肠微生物的影响,并与抗生素作比较,为其在替抗方面的应用提供参考。试验选用600只1日龄健康状况良好的818肉鸡公雏,根据体重一致原则分为4个组,每组6个重复,每个重复25只。对照组饲喂基础饲粮,抗生素组、辣椒碱Ⅰ组和辣椒碱Ⅱ组分别在基础饲粮中添加500 mg/kg恩拉霉素、180 mg/kg辣椒碱和360 mg/kg辣椒碱。试验期40 d。结果表明:1)与对照组相比,抗生素组、辣椒碱Ⅰ组和辣椒碱Ⅱ组肉鸡21日龄体重以及1~21日龄平均日增重显著提高(P<0.05),1~21日龄料重比显著降低(P<0.05);辣椒碱Ⅰ组肉鸡40日龄体重显著提高(P<0.05);抗生素组、辣椒碱Ⅰ组和辣椒碱Ⅱ组肉鸡1~40日龄平均日增重和平均日采食量均显著提高(P<0.05)。2)与对照组相比,抗生素组、辣椒碱Ⅰ组和辣椒碱Ⅱ组肉鸡血浆总蛋白含量均显著提高(P<0.05);辣椒碱Ⅰ组肉鸡血浆葡萄糖、尿酸和丙二醛(MDA)含量均显著降低(P<0.05),血浆甲状腺素和还原型谷胱甘肽(GSH)含量显著提高(P<0.05);同时,辣椒碱Ⅰ组肉鸡血浆MDA含量显著低于抗生素组(P<0.05),血浆GSH含量显著高于抗生素组(P<0.05)。3)辣椒碱Ⅰ组肉鸡空肠食糜中胰蛋白酶和脂肪酶(LPS)活性均显著高于对照组(P<0.05),且辣椒碱Ⅰ组肉鸡空肠食糜中LPS活性显著高于抗生素组(P<0.05)。4)辣椒碱Ⅰ组和辣椒碱Ⅱ组肉鸡空肠小肽转运载体1(PepT1)和B0系统中性氨基酸转运载体(B0AT)mRNA表达量均显著高于对照组(P<0.05),且辣椒碱Ⅰ组显著高于抗生素组(P<0.05)。5)与对照组相比,辣椒碱Ⅰ组肉鸡盲肠中拟杆菌属(Bacteroides)和粪杆菌属(Faecalibacterium)相对丰度显著提高(P<0.05),盲肠中另支菌属(Alistipes)相对丰度显著降低(P<0.05)。以上结果表明,饲粮添加辣椒碱可提高818肉鸡抗氧化能力、肠道消化酶活性、营养物质转运载体相关基因mRNA表达量和有益菌群相对丰度,从而改善生长性能;推荐818肉鸡饲粮添加180 mg/kg辣椒碱替代抗生素。

This experiment was conducted to investigate the effects of capsaicin on growth performance,plasma biochemical indices,intestinal digestive enzyme activities,mRNA expression levels of intestinal nutrient transporter related genes and cecal microorganisms of 818 broilers,and to compare it with antibiotics,so as to provide reference for its application in substitution.A total of 600 healthy 818 male chickens of 1-day-old were divided into 4 groups with 6 replicates per group and 25 chickens per replicate according to the principle of initial body weight consistency.Chickens in the control group were fed a basal diet,and those in the antibiotic group,capsaicin groupⅠand capsaicin groupⅡwere fed the basal diet supplemented with 500 mg/kg emlamycin,180 mg/kg capsaicin and 360 mg/kg capsaicin,respectively.The experiment lasted for 40 days.The results showed as follows:1)compared with the control group,the body weight of chickens at 21 days of age and the average daily gain of chickens from 1 to 21 days of age in the antibiotic group,capsaicin groupⅠand capsaicin group Ⅱ were significantly increased(P<0.05),and the ratio of feed to gain of chickens from 1 to 21 days of age was significantly decreased(P<0.05);the body weight of chickens at 40 days of age in capsaicin groupⅠwas significantly increased(P<0.05);the average daily gain and average daily feed intake of chickens from 1 to 40 days of age in the antibiotic group,capsaicin groupⅠand capsaicin group Ⅱ were significantly increased(P<0.05).2)Compared with the control group,the plasma total protein content of chickens in the antibiotic group,capsaicin groupⅠand capsaicin group Ⅱ was significantly increased(P<0.05);the plasma contents of glucose,uric acid and malondialdehyde(MDA)of chickens in capsaicin group Ⅰ were significantly decreased(P<0.05),and the plasma contents of thyroxine and reduced glutathione(GSH)were significantly increased(P<0.05);meanwhile,the plasma MDA content of chickens in capsaicin group Ⅰ was significantly lower than that in the antibiotic group(P<0.05),and the plasma GSH content was significantly higher than that in the antibiotic group(P<0.05).3)The activities of trypsin and lipase(LPS)in jejunal digesta of chickens in capsaicin group Ⅰ were significantly higher than those in the control group(P<0.05),and the LPS activity in jejunal digesta of chickens in capsaicin group Ⅰ was significantly higher than that in the antibiotic group(P<0.05).4)The mRNA expression levels of small peptide transporter 1(PepT1)and neutral amino acid transporter in system B0(B~0AT)in jejunum of chickens in capsaicin groupⅠand capsaicin group Ⅱ were significantly higher than those in the control group(P<0.05),and those in capsaicin groupⅠwas significantly higher than those in the antibiotic group(P<0.05).5)Compared with the control group,the relative abundances of Bacteroides and Faecalibacterium in cecum of chickens in capsaicin groupⅠwere significantly increased(P<0.05),and the Alistipes relative abundance in cecum was significantly decreased(P<0.05).These results indicate that dietary capsaicin can increase the antioxidant capacity,intestinal digestive enzyme activities,mRNA expression levels of nutrient transporter related genes and relative abundance of beneficial bacteria of 818 chickens,and thus improve the growth performance.It is recommended to supplement with 180 mg/kg capsaicin to the diet instead of antibiotics for 818 chickens.