Aflatoxins (AFs) are toxic metabolites produced by Aspergillus flavus and A. parasiticus. They are natural contaminants of food and feed stuffs. Their presence in feed depresses body weight, feed intake and feed efficiency (FCR) which has been attributed to reduced protein synthesis, impaired nutrient absorbtion and reduce pancreatic digestive enzyme production (Allameh et al., 2005). Prolonged exposure to low concentration of the toxin produce severe changes in fat metabolism, bile duct proliferation and an increase in relative weight of liver, which could be attributed to increased lipid deposition due to impaired fat metabolism (Swamy et al., 1998). The purpose of this study was to determine whether a clinoptilolite (CLI, natural clinoptilolite, a proprietary product of Afrand Toska, an Iranian company), would diminish the adverse effects of a feed containing aflatoxin as measured by responses in body weight, feed intake, FCR and liver weight.