本试验旨在研究模拟鸭肠液中鸭肠液酶粉剂的批次来源与活性贡献对玉米、豆粕、小麦麸消化能力的影响,为模拟鸭肠液中鸭肠液酶粉剂的适宜添加量提供参考。采用嵌套设计,其中独立变量为鸭肠液酶粉剂的批次来源,设3个处理水平,分别为鸭肠液酶粉剂批次1、2、3;嵌套变量为模拟鸭肠液中鸭肠液酶粉剂提供的消化酶活性比例(以胰蛋白酶为基础),设4个处理水平,即0(共用)、25%、50%、75%,分别测定10种模拟鸭肠液对玉米、豆粕、小麦麸3种饲料原料的干物质消化率和酶水解物能值。结果表明:1)3个批次的鸭肠液酶粉剂制备的模拟鸭肠液对玉米、小麦麸的干物质表观消化率、真消化率及酶水解物表观能值、真能值均无显著影响(P>0.05);对豆粕的干物质表观消化率及酶水解物表观能值、真能值无显著影响(P>0.05),但对其干物质真消化率(71.75%~72.24%)有显著影响(P<0.05)。2)同一鸭肠液酶粉剂批次内,酶粉剂提供的消化酶活性的比例从25%增加到75%时,玉米、豆粕、小麦麸的干物质表观消化率和酶水解物表观能值均显著降低(P<0.05),但干物质真消化率相对稳定(最大绝对差值0.95%,相对差值0.95%),酶水解物真能值在鸭肠液酶粉剂提供的消化酶活性的比例从25%增加到50%的范围内也相对稳定(最大绝对差值0.17 MJ/kg,相对差值0.89%)。综合上述结果,不同批次来源的鸭肠液酶粉剂制备的模拟鸭肠液在消化能力上是相等的,模拟鸭肠液中鸭肠液酶粉剂对消化酶总活性的贡献在25%~50%消化能力比较稳定。

This study was conducted to investigate the effects of batch sources and the digestive enzyme activity contribution of intestinal fluid dry powder of ducks in the simulated duck intestinal fluid for ducks on the digestive ability of corn, soybean meal and wheat bran, which would provide a reference for the appropriate amount of intestinal fluid dry powder of ducks in the simulated intestinal fluid for ducks. A nested design was adopted with batch of intestinal fluid dry powder of ducks as an independent variable and the percentage of digestive enzyme activities of intestinal fluid dry powder of ducks in simulated intestinal fluid for ducks as a nested variable. There were 3 treatments of batches 1, 2 and 3 in the independent variable, and 4 treatments of 0 (shared), 25%, 50% and 75% in the nested variable. The dry matter digestibility (DMD) and enzymatic hydrolysate gross energy (EHGE) of corn, soybean meal and wheat bran were measured by in vitro digestion using ten simulated intestinal fluid for ducks, respectively. The results showed as follows: 1) there were no significant effects of simulated intestinal fluid for ducks prepared with 3 batches of intestinal fluid dry powder of ducks on the apparent dry matter digestibility (ADMD), true dry matter digestibility (TDMD), apparent enzymatic hydrolysate gross energy (AEHGE), and true enzymatic hydrolysate gross energy (TEHGE) of corn and wheat bran measured using in vitro digestion (P>0.05). No significant difference in the ADMD, AEHGE and TEHGE (P>0.05), but a significant difference in the TDMD (from 71.75% to 72.24%, P<0.05) of soybean meal digested by simulated intestinal fluid for ducks prepared with 3 batches of intestinal fluid dry powder of ducks were observed. 2) In the same batch of intestinal fluid dry powder of ducks, the ADMD and AEHGE of corn, soybean meal and wheat bran digested by 3 simulated intestinal fluid for ducks significantly were decreased on account of the contribution of digestive enzyme activity percentage changed from 25% to 75%, but the TDMD of corn, soybean meal and wheat bran were stable (the max absolute difference was 0.95%, and relative difference was 0.95%). The TEHGE of these 3 feeds digested by simulated intestinal fluid for ducks were stable (max absolute difference was 0.17 MJ/kg, and relative difference was 0.89%) under the contribution of the digestive enzyme activity percentage changed from 25% to 50%. In conclusion, the digestive abilities of simulated intestinal fluid for ducks prepared with 3 batches of intestinal fluid dry powder of ducks are equal. The digestive abilities of simulated intestinal fluid for ducks are stable under the contribution of the digestive enzyme activities changed from 25% to 50%.