Supplementation with yeast culture improves the integrity of intestinal tight junction proteins via NOD1/NF‐κB P65 pathway in weaned piglets and H2O2-challenged IPEC-J2 cells

•This study explored the effect of yeast culture on the intestinal tight junction proteins and its underlying mechanism.•Yeast culture improved the expression of tight junction proteins in vivo and in vitro.•Yeast culture inhibited the NOD1/NF-κB P65 pathway in the intestine of weaned piglets and H2O2-challenged IPEC-J2 cells.•Occludin and ZO-1 play key roles in the activation of NOD1-mediated pathway.