本试验旨在研究饲粮中添加β-葡聚糖对肉仔鸡生长性能、免疫功能和肠道微环境的影响。选取1日龄爱拔益加（AA）肉仔鸡672只，随机分为4个组，每组14个重复，每个重复12只鸡。对照组饲喂基础饲粮，试验组分别饲喂在基础饲粮上添加100、150和200 g/t β-葡聚糖的试验饲粮。试验期为42 d。结果表明：1）150 g/t剂量组1～21日龄肉仔鸡体增重显著高于对照组（P<0.05）。2）150 g/t剂量组肉仔鸡血清免疫球蛋白含量高于对照组（P>0.05）。3）21日龄时，150 g/t剂量组肉仔鸡盲肠内乳酸菌数量显著高于对照组（P<0.05），空肠和回肠内沙门氏菌数量显著低于对照组（P<0.05）；42日龄时，150和200 g/t剂量组肉仔鸡盲肠内沙门氏菌数量显著低于对照组和100 g/t剂量组（P<0.05）。4）饲粮添加β-葡聚糖对42日龄肉仔鸡空肠绒毛高度与隐窝深度比值影响显著（P<0.05）。由此可见，饲粮中添加适量的β-葡聚糖可提高肉仔鸡出栏重，改善肉仔鸡生长性能，增加盲肠内乳酸菌数量，减少空肠、回肠和盲肠内沙门氏菌数量。

This experiment was conducted to investigate the effects of diet adding β-glucan on growth performance, immune function and intestinal micro environment of broilers. A total of 672 one-day-old Arbor Acres (AA) broilers were randomly allocated to 4 groups with 14 replicates per group and 12 chickens per replicate. The control group was fed a basal diet, while the experimental groups were fed the basal diet supplemented with 100, 150 and 200 g/t β-glucan, respectively. The experiment lasted for 42 days. The results showed as following: 1) the weight gain of broilers aged from 1 to 21 days in 150 g/t groups was significantly higher than that in control group (P<0.05). 2) The serum immunoglobulin content of broilers in 150 g/t group was higher than that in control group (P>0.05). 3) At 21 days of age, the caecal Lactobacillus number of broilers in 150 g/t group was significantly higher than that in control group (P<0.05), while the number of Salmonella in jejunum and ileum was significantly lower than that in control group (P<0.05). At 42 days of age, the caecal Salmonella number of broilers in 150 and 200 g/t group was significantly lower than that in control group and 100 g/t group (P<0.05). 4) The villus height to crypt depth ratio in the jejunum of broilers was significantly influenced by dietary β-glucan supplementation (P<0.05). In conclusion, moderate β-glucan supplementation can improve the commercial body weight, growth performance and the number of Lactobacillus in caecum, while reduce the number of Salmonella in jejunum, ileum and caecum.