不同非淀粉多糖复合酶在肉鸡玉米-豆粕型饲粮中的应用效果

Application Effects of Different Non-Starch Polysaccharide Complex Enzymes on Corn-Soybean Meal Diets for Broilers

本文旨在研究低能量水平的玉米-豆粕型饲粮中添加不同非淀粉多糖（NSP）复合酶对肉鸡生长性能、消化道生理、屠宰性能、肠道微生物数量及经济效益的影响,以确定适宜的NSP复合酶.试验采用单因子完全随机设计,选取900只1日龄的科宝肉公鸡,按体重无差异原则随机分为5个组,正对照组（PC组）饲喂正常能量水平的基础饲粮;负对照组（NC组）饲喂在PC组饲粮的基础上降低270 kJ/kg能量水平的饲粮;NSP复合酶组饲喂在NC组饲粮中分别添加NSP复合酶1（300 g/t）、NSP复合酶2（300 g/t）、NSP复合酶3（500 g/t）的饲粮,每个组10个重复,每个重复18只鸡.试验分为前期（1 ～21 d）、后期（22 ～42 d）2阶段进行.结果表明：1）与PC组相比,NC组第21天平均体重与1～21 d平均体增重均显著降低（P＜0.05）,与NC组相比,NSP复合酶组第21天的平均体重与1～21 d的平均体增重均显著提高（P＜0.05）;与PC组相比,NC组1～21 d和1～42 d的料重比均显著提高（P＜0.05）,与NC组相比,NSP复合酶组1 ～21 d和1～42 d料重比均显著降低（P＜0.05）.2）各组间第21和42天的腺胃、十二指肠、空肠、回肠、盲肠相对重量差异均不显著（P＞0.05）;与PC组相比,NC组第21天的肌胃相对重量显著提高（P＜0.05）,第42天的肌胃相对重量有提高的趋势（P＞0.05）,添加NSP复合酶后肌胃相对重量均有降低.与PC组相比,NC组第21天的空肠、回肠、盲肠相对长度都有所提高,但只有盲肠相对长度差异达显著水平（P＜0.05）;各组间第42天各肠段相对长度均无显著差异（P＞0.05）.3）与PC组相比,NC组第21天的空肠、回肠绒毛高度均有增加,其中回肠绒毛高度差异达显著水平（P＜0.05）;与PC组相比,NC组的十二指肠、空肠和回肠的肌层厚度均有增加,NSP复合酶3组的十二指肠肌层厚度显著提高（P＜0.05）.各组间第42天各段肠道形态指标差异均不显著（P＞0.05）.4）与PC组相比,NC组的屠宰性能指标差异均不显著（P＞0.05）;与NC组相比,NSP复合酶1组和NSP复合酶2组的胸肌率显著增加（P＜0.05）.5）各组间大肠杆菌和双歧杆菌数量差异均不显著（P ＞0.05）;NSP复合酶2组第7天的乳酸杆菌数量显著低于PC组和NC组（P＜0.05）.6）以PC组利润为100％,与之相比NSP复合酶1组提高的利润幅度最大.从结果中可以看出,在低能量水平玉米-豆粕型饲粮中添加NSP复合酶可显著提高肉鸡前期生长性能,对后期生长性能无显著影响,对肉鸡肠道形态具有改善作用,但对屠宰性能和肠道微生物数量无显著影响,另外添加不同的NSP复合酶可不同程度地提高经济效益.综合考虑,本试验中NSP复合酶1的应用效果最优.

This experiment was conducted to investigate the effects of dietary different non-starch polysaccharide （NSP） complex enzymes on growth performance,digestive tract physiology,carcass performance,the number of intestinal microorganism and economic efficiency of broilers fed corn-soybean meal diets.A total of 900 Cobb male broilers aged 1 day were randomly assigned to 5 groups.A positive control group （PC group） was fed a basal diet with normal energy level,and a negative control group （NC group） was fed a diet with a lower energy level （270 kJ/kg metabolizable energy reduction from PC group diet）.Other three complex enzyme groups were fed the NC group diets added with NSP complex enzyme 1 （300 g/t）,NSP complex enzyme 2 （300 g/t） and NSP complex enzyme 3 （500 g/t）,respectively.This experiment included 2 periods,early period （1 to 21 d） and later period （22 to 42 d）.The results showed as follows：1） compared with PC group,the average body weight on 21 d and average body weight gain from 1 to 21 d in NC group were significantly decreased （P 〈 0.05）.Compared with NC group,the average body weight on 21 d and average body weight gain from 1 to 21 d in complex enzyme groups were significantly increased （P 〈 0.05）.Compared with PC group,the feed/gain from 1 to 21 d and 1 to 42 d in NC group was significantly increased （P 〈0.05）,and compared with NC group,the feed/gain from 1 to 21 d and 1 to 42 d in complex enzyme groups was significantly decreased （P 〈 0.05）.2） There was no significant difference in the relative weight of glandular stomach,duodenum,jejunum,ileum and cecun on 21 d and 42 d among all groups （P 〉0.05）.Compared with PC group,the relative weight of muscular stomach in NC group was significantly increased on 21 d （P 〈 0.05） and was tended to be improved on 42 d （P 〉 0.05）,but the relative weight of muscular stomach in complex enzyme groups was decreased （P 〉 0.05）.Compared with PC group,the relative length of jejunum,ileum and cecum on 21 d in NC group was increased,but only the relative length of cecum reached a significant a level （P 〈0.05）.There was no significant difference in the relative length of jejunum,ileum and cecum on 42 d among all groups （P 〉 0.05）.3） Compared with PC group,the villus height of jejunum and ileum on 21 d in the NC group was increased and the villus height of ileum reached a significant level （P 〈0.05）.Compared with PC group,the muscular thickness of duodenum,jejunum and ileum on 21 d in NC group was increased,and the muscular thickness of duodenum in NSP complex enzyme 3 group was significantly increased （P 〈 0.05）.There was no significant difference in intestinal morphology on 42 d among all groups （P 〉 0.05）.4） Compared with PC group,there was no significant difference in carcass performance in NC group （P 〉 0.05）.Compared with NC group,the percentage of breast muscle in NSP complex enzyme 1 group and NSP complex enzyme 2 group was significantly increased （P 〈 0.05）.5） There was no significant difference in the number of Escherichia coli and Bifidobacteria among all groups （P 〉 0.05）.Compared with PC group and NC group,the number of Lactobacilli on 7 d in NSP complex enzyme 2 group was significantly decreased （P 〈0.05）.6） As the profit in PC group of 100%,adding NSP complex enzyme 1 could get the largest profit.In conclusion,NSP complex enzymes in lower energy level corn-soybean meal diets can significantly improve the growth performance in early period of broilers,and has no significant effect on growth performance in later period; the intestinal morphology is improved and there are no significant differences in the carcass performance and the number of intestinal microorganism; the economic efficiency is also be improved in different degrees.In this experiment,the NSP complex enzyme 1 can obtain the best application effects.