Crecimiento y supervivencia de postlarvas de piracanjuba (brycon orbignyanus)

Abstract

This work was conducted in the fish laboratory of the Environmental Station of Itutinga, CEMIG in January 2002. The objective was to evaluate the behavior of piracanjunba (Brycon orbignyanus) post-larvae at different stocking densities and feeding frequencies. The post-larvae were manteined into eighteen plastic rectangular-shaped boxes of 30 liters of volume. All the boxes posessed individual supply and flow of water with a constant renewal, and water temperature controlled (27oC), trough a heating system of the sort utilized in thermal pools. The experimental treatments consisted of three stocking densities (10, 20 and 30 post-larvae/liter) and two feeding frequencies (every 3 and 6 hours). The design was completely randomized with the treatments arranged into a 3 x 2 factorial scheme (stocking density x feeding frequency) with three replicates per treatment. The results showed that the increase of stocking density reduced linearly the fish's survival. There were significant differences (p<0.05) among the feeding frequencies as to survival, feeding the post-larvae in intervals of 3 hours being better. There were no significant difference among the stocking densities and the feeding frequencies as to average weight and growth of the post-larvae (p<0.05). According to the results obtained, it follows that the highest survival was obtained from the density of 10 larvae/liter, fed every 3 hours.