Abstract: The weaning stage of piglets is confronted with challenges such as imperfect intestinal development， unbalanced microbial community，and an immature immune system，resulting in frequent intestinal diseases and severely affecting growth performance. The search for alternatives to antibiotics is urgent. In this study，Lactobacillus reuteri LR1 strain was isolated from the feces of healthy weaned piglets，and its biological characteristics were analyzed，and the effect of its metabolite reuterin on porcine intestinal epithelial cells（IPEC⁃J2）was explored. The results showed that the LR1 strain grew best at 39.25 ℃ and pH=6.387；reuterin had significant antibacterial activity against ETEC K88，and the inhibitory effect increased with the increase of concentration；it had a time ⁃ and concentration⁃dependent effect on the survival rate of IPEC⁃J2 cells，with cytotoxicity in the early stage and an increase in survival rate in the later stage；different concentrations of reuterin（2 μL/mL，20 μL/mL，50 μL/mL） induced the differential expression of interleukins and chemokines in IPEC⁃J2 cells. This study provides a theoretical basis for the application of reuterin as an antibiotic⁃free feed additive in piglet breeding and helps to promote the green and healthy development of the livestock industry.

Key words: Reuterin, Porcine intestinal epithelial cells, Immune regulation, Probiotic metabolite

摘要： 仔猪断奶阶段面临肠道发育不完善、微生物群落失衡及免疫系统不健全等挑战，肠道疾病频发，严重影响生长性能。寻找抗生素替代品迫在眉睫。该研究从健康断奶仔猪粪便中分 离出罗伊氏乳杆菌LR1菌株，分析其生物学特性，并探究其代谢产物罗伊氏菌素对猪肠上皮细胞 （IPEC?J2）的影响。结果表明，LR1菌株在39.25 ℃、pH为6.387时生长最佳；罗伊氏菌素对ETEC K88有显著抗菌性，且抑制效果随浓度升高而增强；对IPEC?J2细胞存活率有时间和浓度依赖性 影响，前期具细胞毒性，后期存活率上升；不同浓度罗伊氏菌素（2 μL/mL，20 μL/mL，50 μL/mL） 引起IPEC?J2细胞中白介素因子和趋化因子的差异表达。该研究为罗伊氏菌素作为无抗饲料添 加剂应用于仔猪养殖提供了理论依据，有助于推动畜牧业绿色健康发展。

关键词: 罗伊氏菌素, 猪肠上皮细胞, 免疫调控, 益生菌代谢产物