饲粮蛋氨酸水平对笼养蛋雏鸭生长性能及抗氧化功能的影响

Effects of dietary methionine level on growth performance and antioxidant function of caged egg-type ducklings

为研究蛋氨酸水平对笼养蛋雏鸭生长性能及抗氧化功能的影响,探讨蛋氨酸的最适宜添加量,试验采用单因素完全随机分组设计,选取健康体重相近的1日龄金定蛋雏鸭180只,随机分成5组,每组6个重复,每个重复6只鸭。Ⅰ组为对照组,饲喂玉米-豆粕型基础饲粮,Ⅱ～Ⅴ组为试验组,分别在基础饲粮中添加0.14%、0.24%、0.34%、0.44%蛋氨酸。试验期为4周。结果表明:(1)Ⅳ组和Ⅴ组蛋雏鸭的平均日增重(ADG)和料重比(F/G)显著优于对照组(P<0.05),雏鸭的平均日采食量(ADFI)和料重比随饲粮蛋氨酸水平的增加呈二次曲线变化,以此为指标估测的蛋氨酸适宜添加水平分别为0.304%和0.377%;(2)Ⅲ组和Ⅳ组血清总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)均显著高于对照组(P<0.05),丙二醛(MAD)显著低于对照组(P<0.05),Ⅲ组和Ⅳ组肝脏的抗氧化指标均与对照组差异显著(P<0.05),以有效抗氧化指标估测的蛋氨酸适宜添加水平分别为:0.311%、0.313%、0.345%、0.323%。由此可见,笼养蛋雏鸭饲喂玉米-豆粕型基础饲粮(含蛋氨酸0.31%)时,蛋氨酸的适宜添加量为0.377%。

The experiment was conducted to study the effects of dietary methionine （Met） level on growth perfor- mance and antioxidant function of caged egg-type ducklings.Using a single factor completely randomized design,a total of 180 1-day-old Jinding egg-type ducklings were randomly divided into 5 groups with 6 replicates of 6 each.Ducks in con- trol group （group Ⅰ ） were fed a basal diet,and experimental groups Ⅱ-Ⅴ were fed the basal diet supplemented with 0.14% ,0.24% ,0.34% and 0.44% Met,respectively.The experiment lasted for 4 weeks.The results showed as follows： （1） compared with control group,the average daily gain and feed to gain in groups Ⅳ,Ⅴ were significantly improved （P 〈 0.05 ）.The average daily feed intake and feed to gain were changed quadratically with increasing dietary Met level, and the estimation values of optimal dietary Met level were 0.304% and 0.377% ,respectively. （2）The serum and liver total anti- oxidation capability （T-AOC）,malonaldehyde （MDA） content,and glutathione peroxidase （GSH-Px） activity of group Ⅲ,ⅣV had significant differences compared with the control group （P 〈 0.05）,and the estimation values of optimal dietary met level were 0.311% ,0.313% ,0.345% and 0.323% ,respectively.In conclusion,the optimal dietary Met level of caged egg-type ducklings fed corn-soybean meal basal diet was 0.377%.