Sobrevivência e crescimento em larvas de piracanjuba (Brycon orbignyanus) submetidas a restrição alimentar

Abstract

The aim of this study was to evaluate the impact of different periods of starvation on piracanjuba Brycan orbignyanus larviculture. Two experimental essays were carried out using a completely randomized design with 6 treatments and 5 replications, both with 10 days duration. The treatments were: feeding throughout the experimental period (J0), two consecutive days of starvation followed by 8 days of feeding (J2); four consecutive days of starvation followed by 6 days of feeding (J4); six consecutive days of starvation followed by 4 days of feeding (J6); eight consecutive days of starvation followed by 2 days of feeding (J8); starvation throughout the experimental period (JN). In the first essay, larvae with 28 hours after hatching (HAH) were used and the point of no return (PNR) and survival rate at the end of the experimental period were analyzed. In the second essay, post-larvae of 10 days after hatching (DAH) were used and zootechnical features (final weight, weight gain, final length, length gain and specific growth rate), compensatory growth and muscle growth were analyzed. The PNR found for piracanjuba larvae was 5.56 days of starvation (133.6 HAH) and the mortality stabilized with 10.6 DAH. In the second essay, significant effects (P <0.05) were observed in the different dietary restriction protocols followed by refeeding period on muscle growth, compensatory growth and other zootechnical parameters evaluated. Survival rate was not affected by dietary protocols (P> 0.05). Thus, it can be stated that piracanjubapost-larvae are able to present compensatory growth when submitted to starvation, and longer periods than two days compromise zootechnical performance and muscle growth during larviculture.