The average performance level was characterised by daily DM intake, energy balance and milk yield which were not affected by the DON and ZEN levels in feed. DON, de-epoxy-DON (de-DON) and ZEN were detected simultaneously in all plasma samples. A linear relationship between toxin intake and plasma levels could be established. Moreover, a linear relationship between DON and de-DON concentration could be derived. It was concluded that DON and ZEN intake of 0.5 mg ZEN/kg and 5 mg DON/kg (current guidance values) had no considerable effects on the performance parameter of dairy cows. Furthermore, increased plasma concentrations of ZEN, DON and de-DON may hint on toxin exposure through the diets.