饲粮中添加5-氨基乙酰丙酸对肉鸡生长性能、抗氧化和免疫指标的影响OA

[Objective]This study was conducted to evaluate the effects of dietary 5-aminolevulinate(5-ALA)supplementation on growth performance,antioxidant and immune indices of broilers.[Method]A total of 192 one-day-old healthy male broiler chicks with similar body weight(39 g±2 g)were randomly allocated into four groups with six replicates per group and eight chicks per replicate.The control group(CON)of broilers was fed a basal diet,while the experimental groups were fed the basal diet supplemented with 300,1 500 and 3 000 mg/kg(5-ALA1,5-ALA5,and 5-ALA10)of 5-ALA,respectively.The experimental period was 42 days,divided into the early stage(1 to 21 days)and the late stage(22 to 42 days).Each chicken was weighed on an empty stomach on the 0th,21st,and 42nd days of the experiment respectively.The feed intake and the number of deaths of broilers during the ages of 1-21,22-42,and 1-42 days were recorded,and the growth performance was calculated.After the experiment,samples of blood,heart,liver,spleen,pancreas,thymus,and bursa of Fabricius from each group of chickens were collected to determine the routine blood indicators and organ coefficients.Serum was isolated to determine its biochemical,hormonal,antioxidant and immune indicators.[Result]①Compared with control group,the feed conversion ratio(F/G)of broilers in each experimental group was significantly decreased from 1 to 21 days(P<0.05).On 42 days,the average body weight and the average daily gain(ADG)throughout the entire period of broilers in 5-ALA1 and 5-ALA5 groups were significantly increased(P<0.05).②Compared with control group,the content of hemoglobin(HGB)in the blood of broilers in both 5-ALA1 and 5-ALA5 groups was significantly increased(P<0.05).③ Compared with control group,the contents of serum total protein(TP)and albumin(ALB)of broilers in 5-ALA1 group were significantly increased(P<0.05).④Compared with control group,the content of triiodothyronine(T3)in the serum of broilers in 5-ALA5 group was significantly increased(P<0.05).⑤Compared with control group,the activity of glutathione peroxidase(GSH-Px)in the serum of broilers in 5-ALA5 group was significantly increased(P<0.05).⑥ Compared with control group,the content of complement 4(C4)in the serum of broilers in 5-ALA5 and 5-ALA10 groups was significantly increased(P<0.05).[Conclusion]Dietary supplementation with 5-ALA could improve growth performance,antioxidant capacity and immune indices of broilers,and high-dose supplementation had no negative effects on growth performance or other parameters in broilers.