饲粮中添加α亚麻酸对脂多糖应激肉鸡生长性能、空肠炎症和抗氧化能力的影响OA

The objective of this study was to investigate the effects of dietary α-Linolenic acid(ALA)on growth performance,jejunal inflammation and antioxidant capacity of broilers challenged by lipopolysaccharide(LPS).A total of 256 one-day-old healthy male Arbor Acres(AA)broilers,were randomly assigned to 4 groups with 8 replicates of 8 birds each:Con group,LPS group,LPS+ALA400 group,and LPS+ALA600 group.Broilers in the Con and LPS groups were fed the basal diet,while those in the LPS+ALA400 and LPS+ALA600 groups received a basal diet supplemented with 400 and 600 mg·kg-1 ALA respectively.On day 20,the dose of 5 mg·kg-1 body weight LPS solution and the equal amount of sterile saline were intraperitoneally injected into LPS-challenged and unchallenged broilers,respectively.The trial lasted for 21 days.The results showed as follows:1)Compared with the LPS group,dietary supplementation of ALA significantly increased the average daily gain on days 20-21 and the ratio of villus height to crypt depth(VH/CD)in broilers(P＜0.05).2)The dietary supplementation of 600 mg·kg-1 ALA significantly enhanced the antioxidant capacity under LPS challenge,as evidenced by the elevated activities of catalase(CAT),total antioxidant capacity(T-AOC),and total superoxide dismutase(T-SOD)in both serum and jejunum tissue.Moreover,there was a significant reduction in malondialdehyde(MDA)levels(P＜0.05).3)Dietary supplementation with 400 mg·kg-1 and 600 mg·kg-1 ALA significantly reduced the levels of inflammatory cytokines IL-1β,IL-6,TNF-α,and IFN-γ in both serum and jejunum of broilers(P＜0.05).4)ALA administration resulted in a significant reduction in both diamine oxidase(DAO)activity and D-lactic acid concentration in broiler serum compared to the LPS group(P＜0.05).Furthermore,mRNA expression of Occludin,Claudin-1,and ZO-1 were significantly increased in jejunum following ALA treatment(P＜0.05).5)In comparison to the Con group,LPS challenge resulted in a significant upregulation of toll-like receptor 4(TLR4),nuclear factor κB(NF-κB),IL-1β,TNF-α,and IFN-γ mRNA expression,and TLR4 and NF-κB protein expression in the jejunum(P＜0.05).Supplementation with ALA effectively mitigated LPS-induced inflammatory response.6)Compared with the LPS group,dietary supplemented with 600 mg·kg-1 ALA resulted in a significant increase in the mRNA expression of nuclear factor E2-relatedfactor 2(Nrf2),hemeoxygenase-1(HO-1),catalase(CAT),glutathione peroxidase(GSH-Px)and SOD,and protein expression of Nrf2 and HO-1 in jejunal of broilers(P＜0.05).In conclusion,dietary ALA demonstrates the potential to mitigate LPS challenge-induced jejunal injury in broilers through modulation of inflammatory response,enhancement of antioxidant capacity,improvement of intestinal barrier integrity,suppression of jejunal TLR4/NF-κB signaling pathway,and activation of Nrf2/HO-1 signaling pathway.