饲粮添加乳化剂与L-肉碱对肉鸡生长性能和血脂指标的影响

本试验旨在研究饲粮添加乳化剂与L-肉碱对肉鸡生长性能和血脂指标的影响。试验采用2×2因子完全随机设计,选用960只1日龄科宝白羽肉公鸡,随机分为4个处理,每个处理6个重复,每个重复40只鸡。试验分为前期(1～21日龄)、后期(22～49日龄)和全期(1～49日龄)。结果表明:1)与对照组相比,添加乳化剂极显著或显著降低了1～21和1～49日龄料重比(P<0.01,P<0.05),提高了21、49日龄血清游离脂肪酸含量(P<0.01);添加L-肉碱或乳化剂与L-肉碱合用均极显著或显著降低了各期料重比(P<0.01,P<0.05),显著降低了21日龄血清甘油三酯和极低密度脂蛋白含量(P<0.05);添加L-肉碱极显著提高了49日龄血清游离脂肪酸含量(P<0.01)。2)主效应分析表明,添加乳化剂显著提高了21日龄血清总胆汁酸、游离脂肪酸含量(P<0.05);添加L-肉碱极显著降低了各期料重比(P<0.01),提高了胸肌率(P<0.01),降低了21、49日龄血清甘油三酯、极低密度脂蛋白含量(P<0.01,P<0.05),降低了21日龄血清总胆固醇和游离脂肪酸含量(P<0.05);乳化剂与L-肉碱的交互作用显著或极显著影响1～21和1～49日龄料重比、21和49日龄血清游离脂肪酸含量(P<0.01,P<0.05)。结果提示,饲粮单独添加乳化剂、L-肉碱或二者合用均可改善肉鸡的饲料利用率,提高胸肌率,降低血清甘油三酯、极低密度脂蛋白含量。单独添加乳化剂或L-肉碱均可提高血清游离脂肪酸含量,二者合用较单独添加降低了血清游离脂肪酸含量。高温(30～35℃)饲养环境下,建议在肉鸡饲粮中单独添加乳化剂或L-肉碱。

Effects of Dietary Emulsifier and L-carnitine on Growth Performance and Serum Lipid Indices of Broilers

This experiment was conducted to investigate the effects of dietary emulsifier and L-carnitine on growth performance and serum lipid indices of broilers.A 2×2 factoral completely random design was adopted,and nine hundred and sixty one-day-old Cobb commercial broilers were randomly allotted into 4 treatments with 6 replicates per treatment and 40 birds per replicate.This experiment included three periods: starter(1 to 21 days of age),grower(22 to 49 days of age) and the whole(1 to 49 days of age) periods.The results showed as follows: 1) compared with the control group,dietary emulsifier significantly decreased feed to gain(F/G) during 1 to 21 and 1 to 49 days of age(P<0.01,P<0.05),and significantly increased serum free fatty acid(FFA) content at 21 and 49 days of age(P<0.01);dietary L-carnitine,or L-carnitine+emulsifier significantly decreased F/G in any period(P<0.01,P<0.05),and significantly decreased the contents of triglycerides(TG) and very low density lipoprotein(VLDL) in serum at 21 days of age(P<0.05);dietary L-carnitine significantly increased serum FFA content at 49 days of age(P<0.05);2) main effect analysis showed that dietary emulsifier significantly increased the contents of total bile acid(TBA) and FFA in serum(P<0.05);dietary L-carnitine significantly decreased F/G in any period(P<0.01),increased the rate of breast muscles(P<0.01),decreased the contents of TG and VLDL in serum at 21 and 49 days of age(P<0.05),and decreased the contents of total cholesterol(TC) and FFA in serum at 21 days of age(P<0.05).The interaction between emulsifier and L-carnitine significantly affected F/G during the starter and the whole periods and serum FFA content at 21 and 49 days of age(P<0.01,P<0.05).In conclusion,the addition of emulsifier,L-carnitine and emulsifier+L-carnitine can improve feed utilization rate,increase the rate of breast muscle,and decrease the contents of TG and VLDL in serum.The addition of emulsifier or L-carnitine can both increase serum FFA content,and emulsifier+L-carnitine can decrease serum FFA content.Supplemental emulsifier or L-carnitine in the diet is better than emulsifier+L-carnitine under high temperature(30 to 35 ℃).