Stocking density effect on growth homogeneity of juvenile pirarucu in confined environments

Abstract

The objective of this work was to evaluate the stocking density over fish growth homogeneity of pirarucu (Arapaima gigas) juveniles in small volumes cages. Twelve 1 m3 net-cages were used in a 120 m2 earth pond consisting of three treatments (15, 20 and 25 fish/m3) with four repetitions each. Fish were stocked with an initial mean weight of 10.1±0.3 g and homogeneous distributed (p>0.05) between treatments. Coefficient of variation for growth and condition factor did not present significant (p>0.05) differences, contrary to consumption and apparent feed conversion (p<0.05). Consumption was inversely proportional to the increment of density, indicating that stockings densities increases are favorable to a better feed use. There were not any observed behavior differences between treatments. Juveniles pirarucu growth was not influenced by the stocking density or intra-specifics interactions.