Macronutrients and essential amino acids on digestive process of the freshwater teleost Matrinxã

Abstract

The objective of this work was to evaluate the effect of macronutrients and essential amino acids on 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 related 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. In conclusion, activities of amylase, protease and lipase of Matrinxãare selectively responsive to addition of free essential amino acids concerning the gut section.

Evaluation of commercial and experimental grower diets for use in intensive culture of Symphysodon aequifasciatus

“…The best growth rates were observed in fish fed the BH + DD diet, this result was also reported by (Wen et al 2018), who combined a wet diet with and hearts (1: 1) and found them to be good growth promoters for S. aequifasciatus. The presence of free amino acids in the diet stimulates feeding chemoreceptors (Santos et al 2021, Camilo et al 2021. In a study with larvae of Piaractus mesopotamicus it was observed that the use of water from the hatching of brine shrimp stimulated the behavior of capturing food, these results being attributed to the presence of dissolved substances (Tesser e Portella 2006).…”