月桂酸替代金霉素对肉鸡腿肌肉品质和抗氧化功能的影响

Effect of Lauric Acid Substitution of Chlortetracycline on Muscle Quality and Antioxidant Function in Broilers

本实验旨在研究月桂酸(lauricacid,LA)对肉鸡肌肉品质、常规营养成分和抗氧化性能的调控作用。实验选用480只1日龄AA肉仔鸡,随机分为4组,每组8个重复,每个重复15只鸡,分别饲喂基础饲粮(对照组)和基础饲粮分别添加75 mg/kg金霉素(抗生素组)、500 mg/kg月桂酸(月桂酸低剂量组;LA500)、1000 mg/kg月桂酸(月桂酸高剂量组;LA1000)的实验饲粮,实验期为42 d。结果表明:与对照组相比,饲粮添加500 mg/kg月桂酸提高了肉鸡腿肌24 h的pH、黄度(b^(*))值和粗脂肪含量,增加了过氧化氢酶(CAT)的活力(P<0.05),上调了SOD2、CAT、GPX1、Nrf2、HO-1的基因表达量(P<0.05),降低了24 h和48 h的滴水损失(P<0.05),饲粮添加1000 mg/kg月桂酸提高了肉鸡腿肌24 h的pH、红度(a^(*))值、黄度(b^(*))值、粗脂肪含量(P<0.05),增加了总抗氧化能力(T-AOC)、总超氧化物歧化酶(SOD)、CAT的活力(P<0.05),上调了SOD1、SOD2、CAT、GPX1、Nrf2、HO-1的基因表达量(P<0.05),降低了24 h的亮度(L^(*))值、滴水损失、48 h的滴水损失和丙二醛(MDA)的含量(P<0.05);与抗生素组相比,添加500 mg/kg月桂酸的饲粮提高了肉鸡腿肌CAT的含量,降低了肉鸡腿肌24 h的滴水损失、MDA的含量(P<0.05),饲粮添加1000 mg/kg月桂酸提高了肉鸡腿肌CAT的含量,降低了肉鸡腿肌24、48 h的滴水损失和MDA的含量(P<0.05)。月桂酸能够改善肉鸡肌肉品质和抗氧化能力,激活Nrf2信号通路相关基因的表达,且效果优于抗生素,饲粮添加1000 mg/kg月桂酸更佳。

In this experiment,the regulatory effects of lauric acid(LA)on muscle quality,conventional nutrients and antioxidant properties of broilers were investigated.A total of 4801-day-old AA broilers were randomly divided into 4 groups with 8 replicates per group and 15 broilers per replicate.Broilers were fed a basal diet(control group),and the basal diet supplemented with 75 mg/kg aureomycin(antibiotic group),500 mg/kg lauric acid(low-dose lauric acid group,LA500),and 1000 mg/kg lauric acid(lauric acid high-dose group,LA1000),respectively.The experiment lasted for 42 days.The results indicated that,compared with the control group,the yellow(b^(*))value,pH at 24 h and ether extract content in leg muscle was increased by dietary supplementation of 500 mg/kg lauric acid,the level of catalase(CAT)was increased,the expression levels of SOD2,CAT,GPX1,Nrf2 and HO-1 genes were up-regulated,and drip loss at 24 h and 48 h of leg muscle in broilers was decreased(P<0.05).PH,a^(*),and b^(*)values at 24 h and the contents of ether extract in leg muscle were increased by dietary 1000 mg/kg lauric acid,the levels of total antioxidant capacity(T-AOC),total superoxide dismutase(SOD)and CAT were increased,the gene expression levels of SOD1,SOD2,CAT,GPX1,Nrf2 and HO-1 were up-regulated,the brightness(L^(*))value and drip loss at 24 h were decreased,drip loss at 48 h was decreased,and the content of malondialdehyde(MDA)in leg muscle of broilers was reduced(P<0.05).Compared with antibiotic group,the level of CAT was increased by dietary 500 mg/kg lauric acid,the drip loss at 24 h was decreased,and the content of MDA of leg muscle in broilers was reduced(P<0.05).The level of CAT was increased by dietary supplementation with 1000 mg/kg lauric acid,the drip loss at 24 h and 48 h was decreased,and the content of MDA in leg muscle of broilers was reduced(P<0.05).Lauric acid could improve muscle quality and antioxidant capacity,activate the related genes expression of Nrf2 signaling pathway,and the effect was better than antibiotics;it was better to add 1000 mg/kg lauric acid to the diet.