EN
The activity of unspecific esterase, alkaline and acid phosphatases in the midgut epithelium of the haneybee exposed to Apitol or Apistan was examined by histochemical methods. Bees in three experimental groups (50 insects in each) were kept in cages for 10 days. Group ID was fed twice at 8 days interval with 2.5 ml of 50% sugar syrup plus 0.1 ml of 2.0% Apitol, group IID was exposed for 10 days to 1/2 strip of Apistan whereas group IIIK fed sugar syrup only served as a control. Apitol and Apistan do not affect the activity of the examined enzymes of the midgut epithelium and bee mortality.