SUMMARY

The effects of zeolite, type "Mikozel", added to the food in three different concentrations of 0.2%, 0.3% and 0.5%, on the changes of some hematologic values in blood serum of trained horses, glucose, Fe, billirubin, total protein and urea concentrtion, were studied in this paper. It was established that all examined biochemical blood serum parameters of trained - horses, Wich were fed in two separated groups - K group (without adding zeolite) and O group (zeolite added), have normal values. The application of zeolite as the forage additive has no sigmificant influence on the improvement of horses' health, but it contributes to the constant maintaiming good physical condition.

          Key words: zeolite, blood serum, concentration, glucose, billirubin, proteins, Fe, urea.