The objective of this study was to investigate the effect of different water salinities on juvenile Hoplias lacerdae during feed training. Salinity levels of 0, 3, 6 and 9 g salt L-1 were used. Juveniles (3.33±0.1 cm and 0.6±0.09 g) were stocked at a density of six fish L-1 in aquaria (10 L volume) with supplementary aeration. Weight gain, length gain, and rates of survival, mortality, and cannibalism were evaluated after 20 days. Total mortality was observed in 0 g […]

The aim of this study was to evaluate the influence of light intensity on the feed training of juvenile giant trahiras (Hoplias lacerdae). A completely randomized design with four light treatments and three replicates was used, and the following light intensities were tested: 204.9; 177.58; 54.64 and 0.00 lux. Juvenile giant trahiras (length = 3.0 ± 0.4 cm and weight = 0.5 ± 0.05 g) were stocked at 6 fish L-1 in 12 rectangular tanks (24 × 20 × 14 […]

The objective of this work was to evaluate suplemenation of vitamin C during feed training of giant trahira fingerlings. An experiment was established in a complete random design with seven treatments (0.0, 17.5, 52.5, 87.5, 122.5, 175.0 and 350.0 mg vitamin C/kg diet) and four repetitions. Giant trahira fingerlings (2.8 ± 0.2 cm) were distributed in 6-L aquaria at the density of 6 fish/L. A basal diet was formulated with 44.0% of crude protein and vitamin C and bovine heart […]

The effects of feeding management strategies on larval rearing of trairao were evaluated in this trial. Eight-d old larvae were counted and stocked in 20 experimental containers (units with volume of 5 L each), with constant aeration and temperature. The stocking density was 30 larvae/L. The following treatments (feeding frequency) were used: F1 – once a day, F2 – twice a day, F3 – three times a day, F4 – four times a day, each with five replicates. Feeding rate […]

An evaluation of training strategies in fingerlings of trairao was carried out. The experimental design included six 20 L tanks with artificial aeration, controlled temperature variation (27±0.5ºC), and continuously darkened (0L:24D), except during daily management. Fingerlings with 2.9±0.2 cm long were kept at a 4 specimens/L and they were allotted to the following treatments: the first was direct offering of artificial diet and the second involved training strategies by means of the replacement of semi humid food for dry food. […]

This experiment was done at Hydrobiology and Pisciculture Section of the Dept of Animal Biology of the University Federal de Viçosa. Fingerlings of Hoplias lacerdae previously trained to accept artificial feed were selected for length and stocked in three tanks with 5000 liters each, until a biomass total of 36.72 g was reached. After 30 days the fishes were selected again for length and distribute into the same tanks, with density of 5 fishes/m², and left again for an additional […]