Influência da densidade de estocagem no cultivo de alevinos de matrinxã Brycon cephalus (Günther, 1869) em condições experimentais

Abstract

The aim of the present experiment was to evaluate the influence of stocking density on the culture of 300 matrinxã fingerlings (Brycon cephalus), of 2.0 ± 0.82g initial weight and 5.7 ± 0.74cm initial length, distributed in 20 ponds (250-L). The utilized experimental design was entirely randomized in four treatments (6, 12, 18 e 24 ind/pond, corresponding to 24, 48, 72, e 96ind/m3) and five replications. The food consisted of a commercial ration of 36% of crude protein, that was supplied ad libitum six times a day during 45 days. A positive linear relation (p<0.05) in biomass, in feed conversion and in size variation weight were verified, due to the higher level of the densities and a quadratic effect (p<0.04) in ration intake. Otherwise, the final weight, weight gain, final length, survival and factor of condition were not affected (p>0.05) for the different stocking densities. The values of physical and chemical parameters remained at adequate levels for fish culture, although densities influenced these values during some days of the experiment. Results showed that the density of 96ind/m3 is the highly recommended, because higher total biomass was observed, which did not affect the fish weight gain.