Compound mycotoxin detoxifier alleviating aflatoxin B1 toxic effects on broiler growth performance, organ damage and gut microbiota

The aim of this study was to evaluate the effects of compound mycotoxin detoxifier (CMD) on alleviating the toxic effect of aflatoxin B1 (AFB1) for broiler growth performance. One-kilogram CMD con-sists of 667 g aflatoxin B1-degrading enzyme (ADE, 1,467 U/g), 200 g montmorillonite and 133 g compound probiotics (CP). The feeding experiment was divided into 2 stages (1-21 d and 22-42 d). In the early stage, a total of 300 one-day-old Ross broilers were randomly divided into 6 groups, 5 replications for each group, 10 broilers (half male and half female) in each replication. In the later feeding stage, about 240 twenty-two-day-old Ross broilers were randomly divided into 6 groups, 8 replications for each group, 5 broilers in each replication. Group A: basal diet; group B: basal diet with 40 mg/kg AFB1; group C: basal diet with 1 g/kg CMD; groups D, E, and F: basal diet with 40 mg/kg AFB1 plus 0.5, 1.0 and 1.5 g/kg CMD, respectively. The results indicated that AFB1 significantly decreased average daily gain (ADG), protein metabolic rate, organ index of thymus, bursa of Fabricius (BF), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and catalase activities in serum, and increased AFB1 residues in serum and liver (P < 0.05). Hematoxylin-Eosin (HE) staining analysis of jejunum, liver and kidney showed that AFB1 caused the main pathological changes with different degrees of inflammatory cell infiltration. How-ever, CMD additions could alleviate the negative effects of AFB1 on the above parameters. The gut microbiota analysis indicated that AFB1 could significantly increase the abundances of Staphylococcus-xylosu, Esherichia-coli-g-Escherichia-Shigella, and decrease Lactobacillus-aviarius abundance (P < 0.05), but which were adjusted to almost the same levels as the control group by CMD addition. The correlative analysis showed that Lactoba-cillus-aviarius abundance was positively correlated with ADG, SOD and BF (P < 0.05), whereas Staphylococcus-xylosus abundance was positively correlated with AFB1 residues in serum and liver (P < 0.05). In conclusion, CMD could keep gut microbiota stable, alleviate histo-logical lesions, increase growth performance, and reduce mycotoxin toxicity. The optimal CMD addition should be 1 g/kg in AFB1-contaminated broilers diet.