本试验旨在研究饲粮中添加葡萄糖氧化酶（GOD）对1~6周龄临武鸭生长性能、血清生化和抗氧化指标、肠道形态结构和微生物多样性的影响，并利用二次回归模型估测其适宜添加水平。选择480羽健康的7日龄临武鸭，随机分为5个组，每组6个重复，每个重复16羽。对照组饲喂为基础饲粮，试验组（A、B、C、D组）分别在基础饲粮中添加10、20、30、40 g/t GOD（活性为10 000 U/g）。试验期35 d。结果表明：1）各组的末重、平均日增重、平均日采食量及料重比均无显著差异（P>0.05）。2）各组的血清总蛋白、白蛋白含量及超氧化物歧化酶、谷胱甘肽过氧化物酶活性无显著差异（P>0.05）。B和C组的血清葡萄糖含量显著高于对照组（P<0.05），A、B、C和D组的血清尿素氮含量均显著低于对照组（P<0.05），D组的血清谷胱甘肽含量显著高于其他各组（P<0.05），C组的血清丙二醛含量显著低于其他各组（P<0.05）。3）B和D组的十二指肠肠壁厚度显著低于A组和对照组（P<0.05），C组的空肠绒毛高度/隐窝深度显著高于D组（P<0.05），A组的回肠绒毛高度显著高于C组（P<0.05），B、C、D组的回肠肠壁厚度显著低于A组和对照组（P<0.05）。4）A和B组的回肠食糜微生物丰富度指数显著高于对照组（P<0.05）。A组的盲肠食糜微生物均匀度指数、香农指数和辛普森指数均显著高于对照组（P<0.05），C组的盲肠食糜微生物丰富度指数显著高于对照组（P<0.05）。由此可见，1~6周龄临武鸭饲粮中适量添加GOD可以改善血清生化指标，增强机体抗氧化能力，并不同程度地改善回肠和盲肠微生物多样性。根据二次回归模型估测，获得最高血清葡萄糖含量时饲粮GOD适宜添加水平为24.04 g/t，获得最低血清尿素氮含量时饲粮GOD适宜添加水平为29.40 g/t，获得最高回肠食糜微生物丰富度指数时饲粮GOD适宜添加水平为19.70 g/t。

This experiment was conducted to investigate the effects of dietary glucose oxidase (GOD) on growth performance, serum biochemical and antioxidant indexes, intestinal morphology and microbial diversity of 1 to 6-week-old Linwu ducks, and to determine the GOD suitable supplement level based on quadratic regression model. Four hundred and eighty healthy 7-day-old Linwu ducks were randomly assigned to 5 groups with 6 replicates per group and 16 ducks per replicate. Ducks in the control group were fed a basal diet, and the others in experimental groups were fed basal diets supplemented with 10, 20, 30 and 40 g/t GOD (activity was 10 000 U/g), respectively. The trail period lasted for 35 days. The results showed as follows:1) there were no significant differences in final weight, average daily gain, average daily feed intake and feed to gain ratio among all groups (P>0.05). 2) There were no significant differences in total protein, albumin contents and superoxide dismutase, glutathione peroxidase activities in serum among all groups (P>0.05). The serum glucose content of groups B and C was significantly higher than that of the control group (P<0.05), the serum urea nitrogen content of groups A, B, C and D was significantly lower than that of the control group (P<0.05), the serum glutathione content of group D was significantly higher than that of other groups (P<0.05), and the serum malondialdehyde content of group C was significantly lower than that of other groups (P<0.05). 3) The duodenal intestinal wall thickness of groups B and D was significantly lower than that of group A and control group (P<0.05), the jejunal villus height/crypt depth of group C was significantly higher than that of group D (P<0.05), the ileum villus height of group A was significantly higher than that of group C (P<0.05), and the ileum intestinal wall thickness of groups B, C and D was significantly lower than that of group A and control group (P<0.05). 4) The richness index of ileum chyme microorganism of groups A and B was significantly higher than that of the control group (P<0.05). The evenness index, Shannon index and Simpson index of cecum chyme microorganism of group A were significantly higher than those of the control group (P<0.05), and the richness index of cecum chyme microorganism of group C was significantly higher than that of the control group (P<0.05). In conclusion, the diet of 1 to 6-week-old Linwu ducks supplemented with proper GOD can improve the serum biochemical indexes, enhance the body antioxidation ability, and improve the microbial diversity of ileum and cecum in different degree. Based on quadratic regression models, the dietary GOD suitable supplement levels of 1 to 6-week-old Linwu ducks to gain maximum serum glucose content, minimum serum urea nitrogen content and maximum richness index of ileum chyme microorganism are 24.04, 29.40 and 19.70 g/t.