The present study aimed to investigate the toxic effect of aflatoxin B1 (AFB1) and the effectiveness of a biological mycotoxin binder (Nutritox®) in detoxifying aflatoxicosis. Ninety one-day-old chicks were chosen and divided into 3 groups. The first group received standard basal diet only, the second group received a basal diet with AFB1 (0.25 mg/kg diet), and the third group received a basal diet with AFB1 (0.25 mg/kg diet) and Nutritox® (1 kg/ton diet). AFB1 feed contamination significantly reduced growth performance and deteriorated FCR. Moreover, it significantly increased serum AST, ALT, and malondialdehyde and significantly decreased serum total protein, albumin, globulin, SOD, CAT activities and glutathione peroxidase gene expression as well. Aflatoxin residues were detected in the liver tissues. Furthermore, the liver and kidney of AFB1 treated group showed pathological changes. The supplementation of Nutritox® significantly reduced aflatoxin levels in the liver and counteracted the negative effects of AFB1.