With the objective of assessing the development of organs of the digestive tract and the enzymatic profile α-amylase, lipase and trypsin, an experiment lasting 21 days was carried out using one-day-old male Avian Farm broiler chicks, reared in heated batteries and fed ad libitum with water and purified diets containing all L-essential amino acids, glutamic acid (nonspecific nitrogen source), minerals and vitamins. A randomized complete design was used with four replications of ten birds. At one, seven, 14 e 21 days of age, four chicks were sacrificed and the liver, pancreas and intestine were removed and weighed to determine the pancreas a-amylase, lipase e trypsin activities. The absolute weights increased with age. The pancreas and intestine relative weight reduced at 21 days of age. Specific activities (UI/mg protein) of α-amylase and lipase were higher on the 1st day, decreased on the 7th day, reaching the maximum peak on the 14th day decreasing again on the 21st day. Trypsin specific activity (UI/mg protein) did not vary with age. The activities per 100 g of body weight of α-amylase, lipase and trypsin (UI/100g body weight) increased from the first to the 14th day of age and showed a reduction on the 21st day. The maximum activities of the digestive enzymes α-amylase and lipase occurred on the 14th day of age. The enzymatic profile of trypsin in general did not alter with age, that can be explained by the fact that the animals were raised on purified diets, that did not stimulate proteolytic enzymes.
digestive enzymes; digestive tract weight; enzymatic development
