乳酸菌微生态制剂对肉鸡生产性能及免疫机能的影响

本实验利用乳酸菌微生态制剂饲喂AA肉鸡,通过检测鸡增重、料重比、免疫器官指数、抗体效价以及盲肠内容物的乳酸菌和大肠杆菌数量,探索乳酸菌微生态制剂对肉鸡生产性能及免疫功能的影响。首先将150只肉鸡随机分成3组,第1组在饮水中添加0.3%的乳酸菌微生态制剂,第2组添加抗生素饮水,第3组为空白对照组,7日龄时接种新城疫疫苗;于每周末称取各组鸡的体重、耗料,计算增重和耗料量;在21日龄和35日龄时,采取各组鸡的脾脏、法氏囊和胸腺、分别计算免疫器官指数;用HI和微量平板滴种法分别检测抗体效价和盲肠内容物乳酸菌、大肠杆菌数量。结果显示,添加0.3%乳酸菌微生态制剂组与对照组和抗生素组鸡比较,分别提高鸡体重15.55%和8.57%(差异显著P<0.05),料重比分别降低5.11%和4.57%;于21日龄和35日龄时检测发现,添加0.3%乳酸菌微生态制剂组与对照组鸡比较,脾脏、法氏囊和胸腺指数分别提高了44.26%1、3.51%、33.96%和67.14%、16.47%3、8.16%;抗体水平分别升高了1.8log2和2 log2,差异显著(P<0.05),与抗生素组比较,抗体效价分别提高了1.4log2和1.75log2,差异显著(P<0.05);另外,21日龄和35日龄时,与对照组比较,添加0.3%乳酸菌微生态制剂鸡盲肠内容物中乳酸菌数量分别增加1.28log2和0.27log2,差异显著(P<0.05),同时分别使大肠杆菌数量减少1.88log2和0.84log2,差异显著(P<0.05)。本研究为合理开发利用乳酸菌微生态制剂提供了理论依据和技术支持。

EFFECTS OF LACTOBACILLUS PROBIOTICS ON THE PERFORMANCE AND IMMUNITY OF BROILERS

This study was aimed to determine the effects of t lactobacillus probioticson AA broilersgrowth performance and immune function by testing the gain of weight,ratio of feed/gain,index of immune organs,antibody level,and quantity of lactobacillus,E.coliin caecal content 150 broilers were randomly assigned to 3 groups,group 1 were fed with 0.3% lactobacillus,group 2 with antibiotic,and group 3 were control.Broilers were vaccinated with NDV vaccine at the age of 7 days;tested the gain of weight and feed consummation at the end of every week;calculated the index of spleen,bursal,andthymuson the 21d and 35d;tested the antibody level with HI test(Haemagglutination inhibition) and determined the quantities of LactobacillusandE.coli in caecal content with micro-plate method respectively.The result shown that compared to antibiotic group and control,the group fed with 0.3% Lactobacillus probotics increasedthe weight by 15.55% and 8.57%(P<0.05),reduced theratio of feed/gain by 5.11% and 4.57% respectively.In Comparison with the control group probiotics also enhanced the index of spleen,bursal,thymus and 67.14%,16.47%,38.16% respectively,the antibody level by1.8log2 and 2 log2(P<0.05) on the 21d and 35d,while compared to antibiotic group the antibody level were increased by 1.4log2 and 1.75log2(P<0.05);on the 21d and 35d the group fed with 0.3% lactobacillusincreased the quantities of lactobacillusby 1.28log2and 0.27log2(P<0.05),reduced the E.coliby 1.88log2 and 0.84log2(P<0.05).This study provide theory and technology support for using lactobacillusprobiotics wisely.