Diferentes níveis de inclusão de hidrolisado de resíduo de pescado nas fases de alevinos e juvenis de tilápias-do-Nilo

Abstract

The present work aimed to evaluate different levels of inclusion of protein hydrolyzate from tilapia residue regarding the productive performance, bromatological composition, morphology of the intestine, muscle, liver and activity of digestive enzymes of fingerlings and juveniles of Nile tilapia fed with diets containing increasing levels of this product. To this end, a completely randomized design was used with six treatments, which consisted of diets with inclusion levels of protein hydrolyzate from fish waste (0; 0.5; 1.0; 1.5; 2.0 and 2.5 %) and four replications, accounting for 24 experimental units. 25 animals were allocated to each 120-liter tank in the Nile tilapia fry production performance test, totaling 600 animals. In the trial with juveniles, 10 animals were allocated, in total 240 animals were used. In the fry performance work, the animals were fed for 40 days and the juveniles for 48 days and at the end of the experimental periods, weight and total length were measured to calculate the productive parameters. The data were subjected to analysis of variance and, when significant, the Tukey test (p<0.05). The fish residue protein hydrolyzate positively influenced (p<0.05) the final weight, weight gain, specific growth rate, body protein composition, intestinal morphology and enzymatic activity of Nile tilapia fingerlings, with better results for the inclusion of 2.0% of this product in diets. In the trial with juveniles, the final weight, final length, weight gain, body protein composition, intestinal morphology and enzymatic activity of Nile tilapia fingerlings were influenced by the inclusion of fish waste protein hydrolyzate, with inclusion of 2% demonstrating better responses. Therefore, it is recommended to include 2% of fish protein hydrolyzate in the diet for fry and juveniles of the same species.