我们先前的研究表明,日粮中添加低聚木糖(XOS)可提高饲料效率,回肠形态,和蛋鸡的养分消化率。本研究的目的是评估XOS对氧化鱼油(OFO)引起的蛋鸡肠粘膜屏障损伤和微生物群失调的缓解作用。将50周龄的384个Hy-Line棕色层随机分为四种饮食处理,包括添加20g/kg新鲜鱼油(FFO组)或20g/kg氧化鱼油(OFO组)的日粮,和XOS添加量为200mg/kg(OFO/XOS200组)或400mg/kg(OFO/XOS400组)的OFO日粮。每种处理具有8个重复,每个12只鸟。OFO处理在实验的7~12周时降低了(P<0.05)禽类的生产性能,降低(P<0.05)回肠黏膜分泌型免疫球蛋白A(sIgA)含量,血清内毒素浓度升高(P<0.05),实验结束时,回肠粘膜claudin-1(CLDN1)和claudin-5(CLDN5)的mRNA表达下调(P<0.05)。日粮添加XOS(400mg/kg)恢复了(P<0.05)这些变化,并进一步提高了(P<0.05)回肠绒毛高度(VH)和绒毛高度与隐窝深度比(VCR)。此外,OFO处理改变了盲肠层的微生物组成,这些改变可能与OFO引起的回肠粘膜损伤有关。补充XOS重塑了OFO饮食的盲肠微生物群,以微生物丰富度和微生物组成变化为特征,包括Firmicutes的增加,Ruminocycaceae,Verrucomicrobia(Akkermansia),Paraprevotella,普雷沃氏菌_9,和蛇形螺旋体,随着丹毒纹状体的减少。Verrucomicrobia(Akkermansia)的丰度增加与CLDN1的回肠VH和回肠粘膜表达改善呈正相关。通过添加XOS减少的丹毒纹状体的丰度与回肠VH呈负相关,VCR,回肠粘膜sIgA含量,以及小带域2,CLDN1和CLDN5的相对表达。总的来说,补充XOS减轻OFO引起的产蛋鸡肠粘膜屏障功能障碍和性能障碍,这可能至少部分归因于肠道微生物群的调节。
Our previous study indicated that dietary xylooligosaccharide (
XOS) supplementation improved feed efficiency, ileal morphology, and nutrient digestibility in laying hens. The objective of this study was to evaluate the mitigative effects of
XOS on intestinal mucosal barrier impairment and microbiota dysbiosis induced by oxidized fish oil (OFO) in laying hens. A total of 384 Hy-Line Brown layers at 50 weeks of age were randomly divided into four dietary treatments, including the diets supplemented with 20 g/kg of fresh fish oil (FFO group) or 20 g/kg of oxidized fish oil (OFO group), and the OFO diets with
XOS addition at 200 mg/kg (OFO/XOS200 group) or 400 mg/kg (OFO/XOS400 group). Each treatment had eight replicates with 12 birds each. The OFO treatment decreased (P < 0.05) the production performance of birds from 7 to 12 weeks of the experiment, reduced (P < 0.05) ileal mucosal secretory immunoglobulin A (sIgA) content, and increased (P < 0.05) serum endotoxin concentration, as well as downregulated (P < 0.05) mRNA expression of claudin-1 (CLDN1) and claudin-5 (CLDN5) in the ileal mucosa at the end of the experiment. Dietary XOS addition (400 mg/kg) recovered (P < 0.05) these changes and further improved (P < 0.05) ileal villus height (VH) and the villus height-to-crypt depth ratio (VCR). In addition, OFO treatment altered cecal microbial composition of layers, and these alterations were probably involved in OFO-induced ileal mucosal impairment as causes or consequences. Supplemental
XOS remodeled cecal microbiota of layers fed the OFO diet, characterized by an elevation in microbial richness and changes in microbial composition, including increases in Firmicutes, Ruminococcaceae, Verrucomicrobia (Akkermansia), Paraprevotella, Prevotella_9, and Oscillospira, along with a decrease in Erysipelatoclostridium. The increased abundance of Verrucomicrobia (Akkermansia) had positive correlations with the improved ileal VH and ileal mucosal expression of CLDN1. The abundance of Erysipelatoclostridium decreased by
XOS addition was negatively associated with ileal VH, VCR, ileal mucosal sIgA content, and the relative expression of zonula occludens-2, CLDN1, and CLDN5. Collectively, supplemental XOS alleviated OFO-induced intestinal mucosal barrier dysfunction and performance impairment in laying hens, which could be at least partially attributed to the modulation of gut microbiota.