Effects of dietary Macleaya cordata extract on growth performance, immune responses, antioxidant capacity, and intestinal development in weaned piglets

This study was conducted to investigate the effects of Macleaya cordata extract (MCE) on growth performance, immune responses, antioxidant capacity, intestinal morphology and microbiota in weaned piglets. A total of 36 weaned piglets [Duroc× (Large White × Landrace)] with an average body weight of 6.55 ± 0.32 kg at weaning were used in a 21-day experiment. Pigs were divided into three treatments (n = 12). Control (basal diet); MCE (basal diet plus MCE) and ABO (basal diet plus 20 mg/kg falvomycin & 100 mg/kg aureomycin). Compared with the control group, piglets in the MCE and ABO groups had higher average daily gain, lower feed efficiency and diarrhea rates (P < 0.05). Serum IgG level in MCE -fed piglets was higher (P < 0.05) than that of control -fed piglets. A higher (P < 0.05) serum the activity of total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) was observed in MCE-fed piglets than those in the control and ABO groups. The addition of MCE increased the amount of Lactobacillus spp. (P < 0.05), while decreased the amount of Salmonella spp. (P < 0.05) and tended to reduce the E. coli population (P < 0.10). Dietary MCE increased villus height and the villus height to crypt depth ratio in the duodenum, jejunum and ileum, and decreased the crypt depth in the jejunum of piglets (P < 0.05). In conclusion, dietary MCE supplementation would exert beneficial effects on growth performance, immune status, antioxidant capacity and the intestinal health and may be used as a potential alternative to antibiotics in weaned piglets.