The performance of pure and hybrid “pintado” Pseudoplatystoma hatchlings at feed training was evaluated. The intestinal coefficient (IC = length of the intestine/total fish lenght) was related to volume and mass and compared by means of analysis of multivariate variance and main components. According to the fish farming station routine, the training lasts about 60 days, when animals are conditioned to feeding on floating dried feed during daylight. Approximately one hundred animals per group were collected in the initial, intermediate […]

The objective of this work was to evaluate the effect of water contaminated by cadmium on the rates of oocyte fertilization and egg hatching, and sperm motility duration on jundiá catfish (Rhamdia quelen). Two trials were performed: in trial 1, it was evaluated the effect of cadmium on the artificial fertilization of oocytes and egg hatching and in trial 2, the effects of cadmium on the sperm motility duration were evaluated. In both trials, it was used a completely randomized […]

The influence of feeding frequency was evaluated on weight gain, specific growth rate, feed conversion and survival of jundiá juveniles. Twelve groups of 280 fish (7.47 ± 1.73 g) were each stocked in twelve ponds (2 fish/m2) and fed to apparent satiety an extruded commercial feed containing 42% CP In four feeding schedules: 1, 2, 3 and 4 times a day, in triplicate, for 120 days (May to September, 2003). Average weight gain was recorded by sampling 10% of the […]

Two experiments were performed to study the effect of stocking rate and growing season on the performance of channel catfish (Ictalurus punctatus). In the first experiment, a completely randomized design in a factorial arrangement was used to study the effect of two stoking rates (0.50 and 0.75 fishes/m2) and two subsequently growing seasons (with five and four month of duration time, respectively). In the second experiment, two stoking rates were compared (0.50 and 0.75 fishes/m2) in a growing season equivalent […]