本试验旨在探讨复合微生态制剂对肉鸡生产性能、肠道菌群、抗氧化指标和免疫功能的影响。将240只1日龄雌性健康肉鸡随机分为4组,每组3个重复,每个重复20只。试验预试期5 d,Ⅰ组为对照组,饲喂基础饲粮;Ⅱ、Ⅲ、Ⅳ组为试验组,在饲喂基础饲粮同时,分别定时在饮水中添加复合微生态制剂A及其佐剂B,其中复合微生态制剂A的添加水平为饲粮的2.0‰,6日龄时开始添加,每周2次,每次饮用量为周采食量2.0‰的1/2;复合微生态制剂佐剂B在7、14和21日龄免疫后分别连续使用3 d,每天1次,每次饮用量为日采食量的0.5‰、1.0‰和2.0‰。正试期为37 d。测定各组生产性能、肠道菌群数量、抗氧化指标和免疫指标。结果表明:1)在每个试验阶段,Ⅱ组肉鸡平均日增重均显著高于对照组(P<0.05),料重比均显著低于对照组(P<0.05),且除7~14日龄和15~21日龄料重比外,Ⅱ组肉鸡平均日增重最高,料重比最低,与其他组差异显著(P<0.05)。2)14日龄和28日龄时,Ⅱ组和Ⅲ组肉鸡盲肠乳酸菌数量均显著高于对照组(P<0.05);14日龄时,Ⅱ组和Ⅲ组肉鸡盲肠大肠杆菌数量均显著低于对照组(P<0.05),28日龄时,仅Ⅱ组肉鸡盲肠大肠杆菌数量显著低于对照组(P<0.05)。3)21、28和35日龄时,Ⅱ组和Ⅲ组肉鸡血浆总抗氧化能力均显著高于对照组(P<0.05),2组之间差异不显著(P>0.05)。4)14日龄和42日龄时,Ⅳ组肉鸡的脾脏指数最高,均显著高于对照组(P<0.05);14、28和42日龄时,Ⅲ组肉鸡的法氏囊指数均较高,显著高于对照组(P<0.05)。由此可知,2.0‰复合微生态制剂A和0.5‰复合微生态制剂佐剂B能够提高肉鸡生产性能,改善其肠道微生态环境,提高其抗氧化能力。同时,复合微生态制剂及其佐剂的添加可在一定程度上增强肉鸡免疫功能。

This experiment was conducted to investigate the effects of compound probiotics on the performance, intestinal microflora, antioxidant indices and immune function of broilers. Two hundred and forty 1-day-old famale broiler chickens were randomly divided into 4 groups with 3 replicates in each group and 20 chickens per replicate. The chickens in the control group (group Ⅰ) were fed a basal diet, and those in other groups (groups Ⅱ, Ⅲ and Ⅳ) were fed the basal diet and drank the water with compound probiotics A and its adjuvant B in different levels. From 6 days of age, compound probiotics A of 2.0‰ diets was supplemented twice a week (half of 2.0‰ of weekly feed intake at a time), and adjuvant B was supplemented for successive 3 days (once a day) after immunization at 7, 14 and 21 days of age, respectively, and the supplemental level of adjuvant B was 0.5‰, 1.0‰ and 2.0‰ of daily feed intake of broilers, respectively. The pre-trial period lasted for 5 days, and the experiment lasted for 37 days. Performance, intestinal microflora, antioxidant and immune indices were determined in different periods. The results showed as follows: 1) in every test period, compared with the control group, the average daily gain of broilers in group Ⅱ was significantly higher (P<0.05), and feed/gain (F/G) was significantly lower (P<0.05); except F/G at 7 to 14 days and 15 to 21 days, the average daily gain and F/G of broilers in group Ⅱ were significantly better than those in the other groups (P<0.05). 2) The number of cecal Lactobacillus of broilers aged 14 and 28 days in groups Ⅱ and Ⅲ was significantly higher than that in the control group (P<0.05); the number of cecal E. coli of broilers aged 14 days in groups Ⅱ and Ⅲ was significantly lower than that in the control group (P<0.05); for 28-day-old broilers, only the number of cecal E.coli in group Ⅱ was significantly lower than that in the control group (P<0.05). 3) The total antioxidant capacity in plasma of broilers aged 21, 28 and 35 days in groups Ⅱ and Ⅲ was significantly higher than that in the control group (P<0.05), but there was no significant difference between group Ⅱ and group Ⅲ (P>0.05). 4) The spleen index of broilers aged 14 and 42 days in group Ⅳ was significantly higher than that in the control group (P<0.05); the bursa of Fabricius index of broilers aged 14, 28 and 42 days in group Ⅲ was higher than that in the control group (P<0.05). In conclusion, the supplementation of 2.0‰ compound probiotics A and 0.5‰ adjuvant B can improve performance, gain a better cecal micro-ecosystem, and enhance the antioxidant function of broilers. Meanwhile, the supplementation of compound probiotics and its adjuvant can improve the immune function of broilers to some degree.