The present study was carried out aiming to investigate the performance, as well to quantify the digestive enzymes activities for the following enzymes: amylase, lipase and trypsin from broiler chickens fed with diets containing different in energy levels and mixed with different probiotic doses. Three hundred and sixty one-day old broilers from the Hubbard-Peterson chick strain were used in this experiment. The birds were fed diets containing 2,900 and 3,200 kcal ME/kg to which were added 0, 200 and 400 ppm of probiotic (Bacillus subtilis - 10(10) sporulated viable cells/gram of product). At 14, 28 and 42 days of age, two birds of each treatment were sacrificed, the pancreas and small intestine withdrawn, weighed and frozen in liquid nitrogen for further enzymatic activity determinations. The experimental design was made up of subdivided parcels with 6 main treatments (two energy levels and three probiotic doses) and 3 secondary treatments (ages) with parcels distributed in 3 randomized blocks. It was not found statistically significant effects when probiotic was added to the diets with respect to performance and enzymatic activities. Energy levels had a significant effect on the performance and lipase and amylase activities (in kg/body weight). It was observed too, that as a function of age there has been a decrease of the lipase activity, with exception of pancreatic amylase and trypsin in g/pancreas. The results obtained in this experiment showed that the addition of probiotic (Bacillus subtilis) in the broiler's diet has not compromised their performance and neither digestive enzymes activities.
broiler chickens; digestive enzymes; probiotics
