EN
The study was carried out on Astra S chickens which were grown on diets containing 11% and 19% proteins. In homogenized pancreas and duodenal contents from control animals and chickens infected with 500 invasive eggs of Ascaridia galli activities of alpha-amylase (FENNEL method), lipase (CHERRY-CRANDALL method) and trypsin (ANSON method) were determined. After 7 weeks of the invasion the activities of these enzymes were higher in duodenal contents and lower in pancreas of infected birds in comparison with the control animals. The differences were significant for alpha-amylase and lipase activities in animals which were given 11% protein diet, and for trypsin activity of chickens groups fed with 19% protein diet.