溶菌酶对肉鸡食糜微生物数量、免疫及生产性能的影响

Effects of lysozyme on micro-organism counts in fresh digesta, immune function and growth performance of broilers

本试验旨在探讨溶菌酶对肉鸡生产性能的影响并简要探讨其作用机制,通过与抗生素作比较,选择食糜微生物数量、免疫机能及生长性能作为评价指标。选择144只1日龄艾维茵肉仔鸡随机分为对照组、抗生素组及2个剂量溶菌酶组(基础日粮分别添加150g/t和300g/t溶菌酶),每组6个重复,每个重复6只鸡。试验鸡只饲喂玉米-豆粕型粉料,地面平养。试验结果表明:与对照组相比,饲料中添加溶菌酶降低了食糜中有害微生物(梭菌和大肠杆菌类)数量(P<0.05);降低了肉鸡免疫器官指数、鸡新城疫抗体水平、IL-1β mRNA和TNF-α mRNA的表达丰度;溶菌酶对肉鸡平均日采食量无显著影响(P>0.05),极显著提高了整个试验阶段肉鸡平均日增重,降低了料重比(P<0.01);溶菌酶组与抗生素组在平均日采食量、日增重及料重比方面无显著性差异(P>0.05)。综合各指标表明,溶菌酶具有类似抗生素的抗菌促生长作用,每吨饲料添加150g溶菌酶呈现出抗菌促生长作用。

This trial was conducted to study the effect of lysozyme on growth performance of borilers and its mechanism.The micro-organism counts in fresh digesta, growth performance and response of immune function to lysozyme were determined in the trial.The experiment had 4 groups including control group fed with basal diet,antibiotics group and lysozyme 1,2group fed with basal diets with antibiotics and basal diets with different dosages of lysozyme （150 g/t and 300 g/t respectively）.The results showed that the treated group had fewer micro-organism counts in fresh digesta than the control group,and the expression of IL-115,TNF-α and serumal antibody titer of newcastle disease of the broilers fed with antibiotics and lysozyme were also lower than the control group.Compared with the broilers fed antibiotics,the broilers fed lysozyme did not show significant difference in final performance （P 〉 0.05）.This results demonstrated that lysozyme was a potential substitute for antibiotics in broiler diets.