低聚糖对蛋鸡生产性能、抗氧化和免疫功能的影响OA

This study aimed to evaluate the effects of different oligosaccharides on the production performance,antioxidant capacity,and immune function of laying hens.A total of 448 healthy 500-day-old laying hens were obtained and randomly assigned to 4 groups,with 8 replicates per group and 14 hens per replicate.The hens were fed with either a basal diet(CON)or experimental diets supplemented with 20 mg/kg chitosan oligosaccharides(COS),50 mg/kg xylooligosaccharides(XOS),or 500 mg/kg mannan oligosaccharides(MOS).The ex-perimental period lasted for 56 days.The results showed that,compared with the CON group,the COS,XOS,and MOS groups significantly reduced the average daily feed intake of the laying hens(P＜0.05).These oligosaccharides significantly increased the serum albumin content and total antioxidant capacity levels(T-AOC)in the birds,but reduced the serum low-density lipoprotein cholesterol content in them(P＜0.05).Specifically,COS enhanced serum total superoxide dismutase(T-SOD)and hepatic catalase(CAT)activities(P＜0.05),whereas MOS improved ovarian T-SOD activity and uterine T-AOC levels(P＜0.05)of the hens.COS and MOS up-regulated the mRNA expression of nuclear factor erythroid 2-related factor 2(Nrf2)in both the liver and ovaries(P＜0.05)of the hens.All three oligosaccharides up-regu-lated hepatic superoxide dismutase 1(SOD1)mRNA expression(P＜0.05),and MOS also elevated its expression in their ovaries.The mRNA expression of hepatic glutathione peroxidase 1(GPX1)in the hens was significantly enhanced by all supplements(P＜0.05).For cat-alase(CAT),COS and XOS up-regulated its hepatic mRNA expression,while COS up-regulated and XOS down-regulated its ovarian ex-pression(P＜0.05).Both COS and MOS significantly increased the mRNA expression of heme oxygenase-1(HO-1)in the liver and ovaries(P＜0.05).XOS and MOS increased serum immunoglobulin A(IgA)content,and COS increased immunoglobulin G(IgG)content(P＜0.05).All the three oligosaccharides significantly reduced the serum content of interleukin-1β(IL-1β)and tumor necrosis factor-α(TNF-α)(P＜0.05).In conclusion,dietary supplementation with COS,XOS,and MOS improved antioxidant status,regulated gene ex-pression in the liver and ovary,and enhanced immune parameters and overall health of the laying hens.