本试验旨在研究北京鸭空肠液中淀粉酶，脂肪酶，胰蛋白酶和糜蛋白酶的总消化能力占所有酶总消化能力的比例，及其他未知酶发生变化后对测试结果的影响。采用单因素完全随机设计，根据肠液酶组成设3个处理，处理间4种主要酶的活性一致。处理1为鸭内源肠液（4种酶+其他酶），处理2为鸭肠液干粉剂+试剂酶（4种酶+其他酶），处理3为试剂酶（4种酶）。每个处理设置5个重复，每个重复1根模拟消化管。分别测定4种饲料原料（玉米、豆粕、棉粕、小麦麸）和4种饲粮的干物质和能量消化率。结果表明：1）不同处理对饲料原料与饲粮干物质、能量消化率有显著影响（P<0.05），影响程度因试验材料不同而有所差异；2）处理2对饲料原料和饲粮的干物质和能量消化率分别为处理1的100.09%~101.76%和100.82%~103.52%；3）处理3对饲料原料和饲粮的干物质和能量消化率分别为处理1的89.38%~110.85%和86.39%~115.63%。结果提示：在鸭空肠液中，淀粉酶，胰蛋白酶，糜蛋白酶和脂肪酶4种主要酶的消化能力占肠液所有酶消化能力的比例86.39%以上，其中其他未知酶发生改变后对测试结果的干扰为1.72%；以鸭肠液干粉剂为主体，采用试剂酶调节4种主要消化酶活性与内源肠液活性等同制备鸭模拟小肠液，是比较理想的制备方法。

Abstract:  This study was conducted to investigate the percentage of the total digestibility of amylase, trypsin, chymotrypsin and lipase to that of all enzymes in jejunal fluid in Beijing ducks in vitro, as well as the influence of the other enzymes changing on the test results. A single-factor completely randomized design was used. Three treatments with same activities of the four main digestive enzymes were set according to the digestive enzymes composition of intestinal fluid. Treatment 1 was endogenous intestinal fluid of ducks (4 main digestive enzymes＋the other digestive enzymes), treatment 2 was a mixture of intestinal fluid dry powder and reagent enzymes (4 main digestive enzymes＋the other digestive enzymes), and treatment 3 was reagent enzymes (4 main digestive enzymes). Each treatment contained 5 replicates and 1 simulative digestive tube per replicate. The dry matter and energy digestibility of 4 feed ingredients (corn, soybean meal, cottonseed meal and wheat bran) and 4 diets were determined. The results showed as follows: 1) there were significant effects of different treatments on the dry matter and energy digestibility of feed ingredients and diets (P<0.05), but the effects on different experimental material were not coincident; 2) the dry matter and energy digestibility in treatment 2 ranged from 100.09% to 101.76% and 100.82% to 103.52% of those in treatment 1, respectively; 3) the dry matter and energy digestibility in treatment 3 ranged from 89.38% to 110.85% and 86.39% to 115.63% of those in treatment 1, respectively. The results indicate that the percentage of the total digestibility of the four main digestive enzymes to that of all the digestive enzymes in duck intestinal fluid was over 86.39%, and the interference of the other enzymes’ changing was 1.72%; the preparation of simulative intestinal fluid is an ideal method that using the endogenous intestinal fluid purification powder as the main ingredient, and adjusting the activities of the four main enzymes to the same levels as endogenous intestinal fluid with regent enzymes.［Chinese Journal of Animal Nutrition, 2011, 23（6）：991 -997］