本试验研究在小麦-豆粕型日粮中添加木聚糖酶对肉鸡免疫功能、肠道形态及微生物菌群的影响。试验选用480只艾维茵肉仔鸡，分为4个组，分别在基础日粮中添加0、1 224、2 449和3 673 IU/kg的木聚糖酶，每组6个重复，每个重复20只肉仔鸡，试验期44 d。结果表明：22日龄小麦-豆粕型日粮中添加木聚糖酶1 224和2 449 IU/kg组脾脏指数和血液E花环显著高于对照组(P＜0.05)，22日龄添加木聚糖酶1 224和2 449 IU/kg组十二指肠指数显著高于对照组和3 673 IU/kg组(P＜0.05)，22日龄3 673 IU/kg组十二脂肠和回肠固有层厚度显著高于对照组(P＜0.05)；44日龄2 449 IU/kg组肉鸡十二指肠的肠绒毛长度显著高于对照组(P＜0.05)，44日龄3 673 IU/kg组肉鸡的E花环和淋巴细胞转化率显著高于对照组(P＜0.05)，1 224 IU/kg组肉鸡回肠乳酸杆菌的数量显著高于其他各组(P＜0.05)。结果显示，在小麦-豆粕型日粮中添加1 224和2 449 IU/kg水平的木聚糖酶可提高肉鸡免疫指标、改善肠道形态及微生物菌群。

This experiment was conducted to study the effect of xylanase in wheat-soybean meal diets on immune indices, intestinal morphology and intestinal flora of broilers. Four hundred and eighty one-day-old Avian broiler chicks were randomly divided into 4 treatments with 6 replicates and 20 broilers in each replicate, added with 0, 1 224, 2 449 and 3 673 IU/kg xylanase in the basal diet, respectively. The experiment lasted for 44 days. The results showed that: compared with control group, the spleen indices and erythrocyte rosette increased significantly in 1 224 and 2 449 IU/kg group on 22 days of age (P＜0.05), in 1 224 and 2 449 IU/kg group on 22 days of age, the duodenum indices increased significantly than control group and 3 673 IU/kg group (P＜0.05), the lamina propria mucosae thickness of duodenum and ileum increased significantly in 3 673 IU/kg group chickens at the age of 22 days of age than control group; the villus length of duodenum increased significantly in 2 449 IU/kg group chick at the age of 44 days of age than control group (P＜0.05), the erythrocyte rosette and the lymphocyte transformation ratio in 3 673 IU/kg group on 44 days of age increased significantly than control group (P＜0.05), the amount of Lactobacillus in ileum in 1 224 IU/kg group on 44 days of age increased significantly than other groups (P＜0.05). The results indicated that diets supplemented with 1 224 and 2 449 IU/kg xylanase in wheat-soybean meal diets could increase immune indices, improve intestinal morphology and flora of broiler.［Chinese Journal of Animal Nutrition, 2009，21(6):931-937］