EFFECT OF THE STOCKING DENSITY ON THE PERFORMANCE OF THE MATRINCHí, BRYCON CEPHALUS (GUNTHER, 1869), CULTURED IN CAGES IN WINTER

Abstract

This work was carried out at the Center of Research and Training on Aquaculture (CEPTA) during the period of May 1 until August 4, 1996. The objective was to identify between the densities of 50, 100 and 150 fishes/m³ that which proportionates the best performance for the cage culture of Brycon cephalus. The means weight and length of the fishes used in this experiment around, ranged between 24 g and 11 cm, respectively. The cages used had 6 m³ (useful volume) being two replications distributed in 3 blocks, with the populational mean characterized for each replication. Using the initial weight in a model as a covariable it was verified that it influenced significantly in the final weight (P=0.037). The stocking density did not influence significantly in the final weight (P=0.907). It was obtained a high coefficient of correlation, r=0.96. The final weights obtained ranged from 35.74 to 40.28 g. In another model having the block as a covariable, it was verified that neither the block (P=0.492) or the stocking density (P=0.659) influenced significantly in the specific growth rate obtained between the first and the last day of experiment. The specific growth rate in weight for the treatments 50, 100 and 150 fishes/m³ was respectively 0.54, 0.45 and 0.41. For all the densities studied, the 150 fishes/m³ was more profitable for proportionate the biggest biomass.