Table 1_Effect of dietary supplementation with aspirin eugenol ester on performance and ileum health in broilers under high stocking density stress conditions.docx

This study investigated the influence of dietary aspirin eugenol ester (AEE) on growth performance, ileum antioxidant capacity, intestinal barrier function and ileum microbiota of broilers subjected to high stocking density stress (HDS). A total of 360 one-day-old Arbor Acres broilers were randomly assigned to four treatment groups: normal density (ND, 14 broilers/m2), normal density + AEE (NDAEE), high density (HD, 22 broilers/m2) and high density + AEE (HDAEE). HDS leads to a significant decrease in broiler performance while reducing the antioxidant capacity of the gut. Morphologic examination of the intestine revealed that HDS causes damage to the intestinal villi. Dietary addition of AEE significantly increased body weight gain and improved antioxidant capacity with restoration of intestinal morphology in broilers with HDS. In addition, HDS resulted in decreased gene expression of ileum tight junction proteins and significantly increased gene expression of inflammatory factors in broilers. Dietary addition of AEE effectively alleviated the decrease in tight junction protein gene expression in broilers with HDS and reduced the expression of HDS-induced inflammatory cytokines through the COX-2-mPGES-1 signaling pathway. AEE supplementation improved microbiota diversity and increased the relative abundance of Lactobacillus and Ileibacterium. Thus, dietary AEE effectively reduced the negative effects of HDS on productivity, gut microbiota and overall health in broilers and could be a worthwhile dietary supplement for offsetting negative effects of stocking stress in broilers.

本研究探究了日粮添加阿司匹林丁香酚酯（aspirin eugenol ester, AEE）对遭受高饲养密度应激（high stocking density stress, HDS）的肉鸡生长性能、回肠抗氧化能力、肠道屏障功能及回肠微生物群的影响。共计选取360只1日龄爱拔益加（Arbor Acres）肉鸡，随机分为4个处理组：正常密度组（ND，14只/m²）、正常密度+AEE组（NDAEE）、高密度组（HD，22只/m²）以及高密度+AEE组（HDAEE）。高饲养密度应激会显著降低肉鸡生产性能，同时削弱肠道抗氧化能力。肠道形态学检测结果显示，高饲养密度应激可造成肠道绒毛损伤。日粮添加AEE可显著提升高饲养密度应激肉鸡的体重增重，改善其抗氧化能力，并修复受损的肠道形态。此外，高饲养密度应激会下调肉鸡回肠紧密连接蛋白的基因表达水平，同时显著上调炎性因子的基因表达。日粮添加AEE可有效缓解高饲养密度应激肉鸡的紧密连接蛋白基因表达下调情况，并通过COX-2-mPGES-1信号通路减轻该应激诱导的炎性细胞因子表达。补充AEE还可改善微生物群多样性，提升乳杆菌属（Lactobacillus）及Ileibacterium的相对丰度。综上，日粮添加AEE可有效缓解高饲养密度应激对肉鸡生产性能、肠道微生物群及整体健康的负面影响，有望成为一种颇具应用价值的日粮补充剂，用以抵消肉鸡饲养应激带来的不利影响。