益生素对肉仔鸡生长性能及免疫器官发育的影响

研究益生素对AA肉仔鸡的生长性能及免疫器官发育的影响.对照组饲喂玉米-豆粕型基础日粮,抗生素组在基础日粮中添加50mg/kg金霉素,Ⅰ、Ⅱ组分别添加200、400mg/kg益生素.结果显示:21日龄Ⅰ、Ⅱ组平均日采食量较对照组分别降低1.4％和1.9％,料重比分别降低6.7％和6.7％；Ⅰ组法氏囊重和法氏囊指数分别提高35.4％和36.9％,Ⅱ组胸腺重和胸腺指数分别提高4.5％、9.5％.42日龄Ⅰ、Ⅱ组平均日采食量较对照组分别提高9.9％和3.7％,料重比分别降低1.4％和2.3％；对照组脾脏指数略高于Ⅰ组,显著高于Ⅱ组；Ⅰ、Ⅱ组胸腺重、胸腺指数及法氏囊指数均显著高于对照组.21日龄Ⅰ、Ⅱ组平均日采食量较抗生素组分别提高0.9％和0.4％,料重比分别降低3.1％和3.1％；42日龄Ⅰ、Ⅱ组平均日采食量分别提高5.7％和3.7％,料重比分别降低1.9％和2.8％.以添加水平200 mg/kg的效果较好.

Effects of probiotics on growth performance and immune organs development of broilers

The effects of probiotics on growth performance and immune organs of broilers was evaluated.The control group was fed with the corn-soybean basal diet;the antibiotics group was fed with basal diet added 50 mg/kg Aureomycin;and the experimental group I and Ⅱwere fed with the basal diet supplemented with 200 mg/kg,400 mg/kg probiotics respectively.The results showed that compared with control group,the average daily intake of experimental group Ⅰ and Ⅱ with 21days feeding decreased 1.4% and 1.9%;feed to gain ratio decreased 6.7% for both group.The weight and organ index of bursa fabricius increased 35.4% and 36.9% for group I;the weight and organ index of thymus increased 4.5% and 9.5% for group Ⅱ.The average daily intake of experimental group Ⅰ and Ⅱ with 42 days feeding increased 6.9% and 2.9%;feed to gain ratio decreased 2.0% and 3.0%.The organ index of spleen for control group is slightly higher than experimental group I and Ⅱ,but the organ indexes of thymus and bursa fabricius and the weight of thymus were all lower compared with both experimental groups.Compared with antibiotics group,the average daily intake of experimental group Ⅰ and Ⅱ with 21 days feeding increased 0.6% and 0.4%;feed to gain ratio decreased 3.1% for both group.The average daily intake of experimental group Ⅰ and Ⅱ with 42 days feeding increased 4.5% and 2.9%;feed to gain ratio decreased 2.0% and 3.0%.Feed with 200 mg/kg supplementation showed best result.