Macronutrients and essential amino acids on the digestive process of the freshwater teleost matrinxã (Brycon amazonicus)

Abstract

The objective of this work was to evaluate the effect of macronutrients and essential amino acids on the digestive process of the freshwater teleost matrinxã (Brycon amazonicus). Juveniles were fed with diets containing starch plus free amino acids or oil plus free amino acids for 15 days. These fish were compared with others fed with diets containing starch or oil without addition of free amino acids. After the experimental span, 12 fish from each treatment were randomly sampled to collect stomach, pyloric cecum, anterior and posterior intestine for assaying digestive enzymes activity. Increase of gastric proteolysis due to dietary amino acids were observed. Amylolytic, proteolytic and lipolytic activities in intestine sections were also positive due to dietary amino acids. However, proteolytic and lipolytic activities in pyloric cecum were not responsive to dietary changes. Moreover, the absence of starch in the diets resulted in decrease of amylolysis, and very low levels of oil did not change the lipolytic activity. Based on the results of the present study, the inclusion of essential amino acids in diets for juvenile matrinxã promotes a nutrition strategy to improve digestive function.