The potential of Hoplias malabaricus (Characiformes: Erythrinidae), a Neotropical carnivore, for aquaculture

Abstract

We describe key production-related traits of trahira (Hoplias malabaricus), an aquaculture candidate species, in a semi-intensive fish farming system. We quantified growth from hatch through grow-out at two stocking densities and evaluated fillet protein, lipids and fatty-acid content. We made 2430 observations of growth and morphometrics on 270 juvenile fish allocated to four fish ponds, two at 5 fish/m2 (90 animals) and two at 10 fish/m2 (180 animals) through 11 months. The fish reached an average length of 27.5 cm (±0.38) and 27.0 cm (±0.24), and weight of 263.0 g (±10.54) and 246.7 g (±6.89), respectively, at the low and high densities. There was no significant difference in weight (P > 0.05) between the densities for any of the parameters assessed, and hence the same growth curve applied to both densities (A = 292.9; B = 28.1; and K = 0.65). Standard length, however, differed significantly (P < 0.05) between densities, with K = 0.35 at the low and K = 0.29 at the high density. At both stocking densities, total lipids increased throughout the trial, while protein content decreased. Oleic acid (C18:0) increased throughout the experimental period, while docosahexaenoic acid and the n3/n6 profile decreased, with no differences among stocking densities. Hoplias malabaricus may prove a viable aquaculture species in Neotropical regions, where development of native species may contribute to sustainable aquaculture production.