The effects and safety of dietary supplementation with Microcin C7 (C7) were evaluated in 216 weaned piglets. The pigs were given a control corn–soybean meal basal diet or C7 diet (control diet supplemented with 250, 500, 750, 1000, or 5000 mg C7/kg diets). Compared with the control group, the 500 mg/kg C7 supplementation group had better intestinal morphological indicators (p p p p p p < 0.05). Compared with the control diet, 5000 mg/kg C7 supplementation had no significant adverse effect on all parameters. Overall, the 250–500 mg/kg dose had the best effect, and the highest dose (5000 mg/kg) posed no toxicity risk. Therefore, C7 appears safe for use as an alternative to antibiotic growth promoters in weaned piglets.
