本试验旨在研究肉鸡小麦-豆粕型饲粮中添加不同水平复合酶制剂（含木聚糖酶850 U/g、纤维素酶750 U/g、β-葡聚糖酶50 U/g、植酸酶2 000 U/kg）对肉鸡消化器官内源消化酶活性和养分利用率的影响。试验选用336只1日龄爱拔益加肉鸡公雏，随机分为7个组，每组6个重复，每个重复8只鸡。对照组Ⅰ饲喂玉米-豆粕型基础饲粮，对照组Ⅱ饲喂小麦-豆粕型基础饲粮，试验Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组在小麦-豆粕型基础饲粮中分别添加1 000、1 500、2 000、2 500、3 000 mg/kg复合酶制剂。试验期42 d。结果表明：1）21和42日龄时，试验Ⅲ组肉鸡腺胃和肌胃胃蛋白酶活性略低于对照组Ⅰ（P>0.05），其他试验组极显著低于对照组Ⅰ（P<0.01）。2）42日龄时试验Ⅲ组肉鸡胰腺淀粉酶、胰蛋白酶和糜蛋白酶活性与对照组Ⅰ相比差异不显著（P>0.05），21和42日龄时其他试验组显著或极显著低于对照组Ⅰ（P<0.05或P<0.01）；21日龄时试验Ⅰ~Ⅴ组和42日龄时试验Ⅲ组肉鸡胰腺脂肪酶活性与对照组Ⅰ相比差异不显著（P>0.05）。3）42日龄时试验Ⅲ组肉鸡十二指肠淀粉酶、脂肪酶和胰蛋白酶活性以及试验Ⅳ组肉鸡十二指肠脂肪酶和胰蛋白酶活性与对照组Ⅰ相比差异不显著（P>0.05），21日龄时试验Ⅱ~Ⅴ组和42日龄时试验Ⅲ~Ⅳ组肉鸡十二指肠糜蛋白酶活性与对照组Ⅰ相比差异不显著（P>0.05），其他试验组上述指标显著或极显著低于对照组Ⅰ（P<0.05或P<0.01）。4）21日龄时试验Ⅲ组肉鸡空肠淀粉酶和胰蛋白酶活性、试验Ⅲ组和试验Ⅳ组肉鸡空肠脂肪酶和糜蛋白酶活性略低于对照组Ⅰ（P>0.05），42日龄时试验Ⅲ~Ⅳ组肉鸡空肠淀粉酶活性、试验Ⅱ~Ⅲ组肉鸡空肠脂肪酶活性以及试验Ⅲ组肉鸡空肠糜蛋白酶活性与对照组Ⅰ相比差异不显著（P>0.05），其他试验组上述指标显著或极显著低于对照组Ⅰ（P<0.05或P<0.01）。5）21日龄时试验Ⅲ组和试验Ⅳ组以及42日龄时试验Ⅲ组肉鸡回肠淀粉酶、脂肪酶、胰蛋白酶和糜蛋白酶活性均略低于对照组Ⅰ（P>0.05），其他各试验组（21日龄时试验Ⅳ组除外）均极显著低于对照组Ⅰ（P<0.01）。6）与对照组Ⅱ比较，试验Ⅱ~Ⅴ组肉鸡腺胃、肌胃、胰腺和小肠各段内源消化酶活性显著或极显著提高（P<0.05或P<0.01）。7）21日龄时试验Ⅲ~Ⅴ组和42日龄时试验Ⅳ~Ⅴ组肉鸡饲粮总能、粗脂肪、粗蛋白质表观利用率和真利用率与对照组Ⅰ相比差异不显著（P>0.05），其他试验组显著或极显著低于对照组Ⅰ（P<0.05或P<0.01），21和42日龄时试验Ⅲ~Ⅴ组显著或极显著高于对照组Ⅱ（P<0.05或P<0.01）；21日龄时试验Ⅳ~Ⅴ组肉鸡钙表观利用率和试验Ⅴ组肉鸡钙真利用率显著或极显著高于对照组Ⅰ和对照组Ⅱ（P<0.05或P<0.01），42日龄时试验Ⅳ~Ⅴ组肉鸡钙表观利用率和真利用率极显著高于对照组Ⅱ（P<0.01）；42日龄时试验Ⅲ~Ⅴ组肉鸡磷表观利用率和真利用率极显著高于对照组Ⅰ（P<0.01），21和42日龄时试验Ⅱ~Ⅴ组肉鸡磷表观利用率和真利用率显著或极显著高于对照组Ⅱ（P<0.05或P<0.01）。综上所述，肉鸡小麦-豆粕型饲粮中添加2 000~2 500 mg/kg外源复合酶制剂可使消化器官内源消化酶活性提高至与玉米-豆粕型饲粮接近，添加2 000~3 000 mg/kg外源复合酶制剂可使肉鸡对小麦-豆粕型饲粮养分利用率提高至接近或优于玉米-豆粕型饲粮。

The purpose of this study was to investigate the effects of different dietary levels of compound enzyme preparation (containing 850 U/g xylanase, 750 U/g cellulase, 50 U/g β-glucanase and 2 000 U/kg phytase) on endogenous digestive enzyme activity and nutrient utilization in wheat-soybean meal type diet for broilers. A total of 336 one-day-old Arbor Acres male broiler chickens were randomly divided into 7 groups with 6 replicates in each group and 8 chickens in each replicate. The control group Ⅰ was fed a corn-soybean meal type diet, the control group Ⅱ was fed a wheat-soybean meal type diet, and the experimental groups Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ were fed the wheat-soybean meal type diets supplemented with 1 000, 1 500, 2 000, 2 500 and 3 000 mg/kg compound enzyme preparation, respectively. The experiment lasted for 42 days. The results showed as follows: 1) at the age of 21 and 42 days, the pepsin activity in glandular stomach and muscle stomach of broilers in experimental group Ⅲ was slightly lower than that in the control group Ⅰ (P>0.05), which in the other experimental groups was extremely significantly lower than that in the control group Ⅰ (P<0.01). 2) The activities of amylase, trypsin and chymotrypsin in pancreas of broilers at the age of 42 days in experimental group Ⅲ were not significantly different compared with the control group Ⅰ (P>0.05), while those of broilers at the age of 21 and 42 days in the other experimental groups were significantly or extremely significantly lower than those in the control group Ⅰ (P<0.05 or P<0.01). The lipase activity in pancreas of broilers at the age of 21 days in experimental groups Ⅰ to Ⅴ and broilers at the age of 42 days in experimental group Ⅲ was not significantly different compared with the control group Ⅰ (P>0.05). 3) At the age of 42 days, the activities of amylase, lipase and trypsin in duodenum of broilers in experimental group Ⅲ and the activities of lipase and trypsin in duodenum of broilers in experimental group Ⅳ were not significantly different compared with the control group Ⅰ (P>0.05). The chymotrypsin activity in duodenum of broilers at the age of 21 days in experimental groups Ⅱ to Ⅴ and broilers at the age of 42 days in experimental groups Ⅲ to Ⅳ was not significantly different compared with the control group Ⅰ (P>0.05). The above indices in the other experimental groups were significantly or extremely significantly lower than those in the control group Ⅰ (P<0.05 or P<0.01). 4) At the age of 21 days, the activities of amylase and trypsin in jejunum of broilers in experimental group Ⅲ and the activities of lipase and chymotrypsin of broilers in experimental groups Ⅲ and Ⅳ were slightly lower than those in the control group Ⅰ (P>0.05). At the age of 42 days, the amylase activity in jejunum of broilers in experimental groups Ⅲ to Ⅳ, the lipase activity in jejunum of broilers in experimental groups Ⅱ to Ⅲ, and the chymotrypsin activity of broilers in experimental group Ⅲ were not significantly different compared with the control group Ⅰ (P>0.05). The above indices in the other experimental groups were significantly or extremely significantly lower than those in the control group Ⅰ (P<0.05 or P<0.01). 5) The activities of amylase, lipase, trypsin and chymotrypsin in ileum of broilers at the age of 21 days in experimental groups Ⅲ and Ⅳ and broilers at the age 42 days in experimental group Ⅲ were slightly lower than those in the control group Ⅰ (P>0.05), but those in the other experimental groups (except for experimental group Ⅳ at the age of 21 days) were extremely significantly lower than those in the control group Ⅰ (P<0.01). 6) Compared with the control group Ⅱ, the endogenous digestive enzyme activities in glandular stomach, muscle stomach, pancreas and all small intestine paragraphs of broilers in experimental groups Ⅱ to Ⅴ were significantly or extremely significantly increased (P<0.05 or P<0.01). 7) The apparent utilization and true utilization of dietary gross energy, ether extract and crude protein of broilers at the age of 21 days in experimental groups Ⅲ to Ⅴ and broilers at the age of 42 days in experimental groups Ⅳ to Ⅴ were not significantly different compared with the control group Ⅰ (P>0.05), which in the other experimental groups were significantly or extremely significantly lower than those in the control group Ⅰ (P<0.05 or P<0.01), and those in the experimental groups Ⅲ to Ⅴ at the age of 21 and 42 days were significantly higher than those in the control group Ⅱ (P<0.05 or P<0.01). At the age of 21 days, the calcium apparent utilization of broilers in experimental groups Ⅳ to Ⅴ and the calcium true utilization of broilers in experimental group Ⅴ were significantly or extremely significantly higher than those in the control groups Ⅰ and Ⅱ (P<0.05 or P<0.01). At the age of 42 days, the apparent utilization and true utilization of calcium of broilers in experimental groups Ⅳ to Ⅴ were extremely significantly higher than those in the control group Ⅱ (P<0.01). The apparent utilization and true utilization of phosphorus of broilers at the age of 42 days in experimental groups Ⅲ to Ⅴ were extremely significantly higher than those in the control group Ⅰ (P<0.01), and the apparent utilization and true utilization of phosphorus of broilers at the age of 21 and 42 days in experimental groups Ⅱ to Ⅴ were significantly or extremely higher than those in the control group Ⅱ (P<0.05 or P<0.01). In conclusion, dietary 2 000 to 2 500 mg/kg exogenous compound enzyme preparation in wheat-soybean meal type diet for broilers can increase the endogenous digestive enzyme activities in digestive organs to be basically consistent with the corn-soybean meal type diet, and dietary 2 000 to 3 000 mg/kg exogenous compound enzyme preparation can increase the nutrient utilization of broilers to be close or better than the corn-soybean meal type diet.