Growth curve of pacu and the patinga hybrid farmed in a semi-intensive system

The growth curve is a tool that can be used to determine the performance potential of fish at different ages. The aim of this study was to evaluate the growth curve of pacu (P. mesopotamicus) and the patinga hybrid (P. mesopotamicus × P. brachypomus) cultivated in a semi-intensive system. In the initial phase of the experiment, the pacu and patinga fish weighed 32.6 ± 7.5 g and 24.9 ± 7.1 g, respectively. The Gompertz model was adopted to describe the growth curve. At the end of the experiment, body weight, standard length, head length, body height and body width did not differ significantly between the pacu (625.9 g; 25.6 cm; 7.2 cm; 12.1 cm; 4.5 cm) and the patinga hybrid (727.1 g; 27.3 cm; 7.6 cm; 13.2 cm; 4.9 cm). The asymptotic value (parameter A), relative growth rate (parameter B), and age at the inflection point (parameter C) of the growth curve of the two species were similar for weight and for the evaluated morphometric traits. The asymptotic values obtained for weight in the pacu and the patinga hybrid were 1212.0 g and 1348.0 g, respectively. The growth curve of the patinga hybrid is similar to that of pacu, contrasting with the belief of many fish farmers.