Effect of Stocking Density on the Growth of the Ornamental Fish Laetacara Dorsigera

Laetacara dorsigera is a fish species that has excellent potential for ornamental fish farming. The present study aimed to evaluate the effect of stocking density on its growth in two experiments, with three treatments and four repetitions, lasting 45 days each. The first experiment used 0.25, 0.50, and 0.75 fish L-1, and the second used the best density found in the first experiment, plus densities of 0.30 and 0.40 fish L-1. The measured zootechnical parameters were survival rate, mean total lengths, and mean initial and final weights, as well as relative growth, specific growth, and weight gain rates. A significant difference was observed in the first experiment for the final length (18.7 and 17.5 mm, in the densities of 0.25 and 0.50 fish L-1, respectively), relative growth rate percent, and specific growth rate weight% (0.25 fish L-1) and survival (0.50 fish L-1). In the second experiment, there was no significant difference for the densities tested. The density of 0.50 fish L-1 is the most viable, due to the greater final survival achieved and no significant difference for the other parameters analyzed.