Clostridium butyricum relieves diarrhea by enhancing digestive function, maintaining intestinal barrier integrity, and relieving intestinal inflammation in weaned piglets

•Weaned pigs fed with 250 to 1000 mg/kg C. butyricum diets decreased the diarrhea incidences compared with the control.•C. butyricum could relive diarrhea by improving digestive enzyme activity, maintaining intestinal barrier integrity, and relieving intestinal inflammation.•C. butyricium supplementation could maintain the intestinal barrier integrity by enhancing the expression of intestinal zonula occludens-1 and alkaline phosphatase rather than the sIgA.•To achieve better gut health in weaned piglet, the optimal dose for dietary supplementation with C. butyricum was 500 mg/kg.