The declines in laying performance during the late production period have adverse effects on the length of the production cycle. Improving the nutrition of laying hens is a crucial measure to reverse this declination. This study investigated the effect of selenium yeast (SY) on egg production, ileal gene expression and microbiota, as well as elucidating their associations in aged laying hens. A total of 375 Jinghong laying hens at 76 weeks old were randomly assigned into 5 dietary treatments, which included a selenium-deficient basal diet based on corn-soybean meal, and dietary supplementation of SY at 0.15, 0.30 and 0.45 mg/kg, and sodium selenite at 0.45 mg/kg. The results showed that SY ameliorated the depression in aged laying performance in the 0.30 mg/kg group (P < 0.01). Selenium yeast significantly increased ileum selenium concentration (P < 0.05), and SY groups had higher selenium deposition efficiency than the sodium selenite group. Functional enrichment and Short Time-series Expression Miner (STEM) analysis indicated that SY activated metabolic progress (e.g., glycerolipid metabolism, glycerophospholipid metabolism, and fatty acid metabolism), immune response and oxidative stress response. Four hub genes including thioredoxin reductase 1 (TXNRD1), dihydrolipoamide dehydrogenase (DLD), integrin linked kinase (ILK) and leucine zipper tumor suppressor 2 (LZTS2) were involved in intestinal metabolism which was closely associated with selenium deposition/status. Moreover, the relative abundance of Veillonella, Turicibacter and Lactobacillus was significantly increased, but the relative abundance of Stenotrophomonas was significantly decreased by SY supplementation. Multi-omics data integration and Canonical correspondence analysis (CCA) showed that both the ileum selenium content and the laying rate were highly correlated with pathways and bacteria enriched in metabolism and immune response. Meanwhile, the “switched on” gene prostate stem cell antigen (PSCA) had a positive relationship with Veillonella and a negative relationship with the opportunistic pathogens Stenotrophomonas. Overall, our study offered insight for the further exploration of the role of SY on boosting egg production and balancing ileum intestinal flora in aged laying hens.

生产后期铺设性能的下降对生产周期的长度产生不利影响。改善蛋鸡的营养是扭转这种下降趋势的关键措施。本研究调查了硒酵母 (SY) 对产蛋量、回肠基因表达和微生物群的影响，并阐明了它们在老年蛋鸡中的关联。将 375 只 76 周龄的景红蛋鸡随机分为 5 个日粮处理，包括以玉米豆粕为基础的缺硒基础日粮，日粮中添加 0.15、0.30 和 0.45 mg/kg 的 SY，以及亚硒酸钠，0.45 mg/kg。结果表明，SY改善了0.30 mg/kg组老年产蛋性能下降（P < 0.01)。硒酵母显着增加回肠硒浓度（P  < 0.05），SY组硒沉积效率高于亚硒酸钠组。功能富集和短时间序列表达矿工 (STEM) 分析表明，SY 激活了代谢进程（例如，甘油脂代谢、甘油磷脂代谢和脂肪酸代谢）、免疫反应和氧化应激反应。四个中心基因，包括硫氧还蛋白还原酶 1 ( TXNRD1 )、二氢硫辛酰胺脱氢酶 ( DLD )、整合素连接激酶 ( ILK ) 和亮氨酸拉链肿瘤抑制基因 2 ( LZTS2)) 参与与硒沉积/状态密切相关的肠道代谢。此外，添加 SY 后，韦荣菌属、Turicibacter和Lactobacillus的相对丰度显着增加，但窄食单胞菌的相对丰度显着降低。多组学数据整合和典型对应分析（CCA）表明，回肠硒含量和产蛋率都与代谢和免疫反应富集的途径和细菌高度相关。同时，“开启”基因前列腺干细胞抗原（PSCA）与韦荣氏菌呈正相关，与机会致病菌呈负相关。窄食单胞菌。总体而言，我们的研究为进一步探索 SY 在提高产蛋鸡产蛋量和平衡回肠肠道菌群中的作用提供了见解。