Анотация: Zearalenone (ZEA) is found in contaminated feeds and its oestrogenic effects depend on its biotransformation fate. The current study aimed to investigate the hepatic biotransformation of ZEA in horse by using freshly isolated hepatocytes and also hepatic subcellular fractions. ZEA was incubated with hepatocytes and hepatic intracellular subfractions in the presence of nicotinamide dinucleotide phosphate (NADPH), and the products were determined by high-performance liquid chromatography