Tambaqui Production at Different Stocking Densities in RAS: Growth and Physiology.

Stocking densities were evaluated for the rearing tambaqui in an RAS system. Experiment 1 used juveniles weighing 0.54 g at the following densities for 15 days: D0.3—0.3; D0.6—0.6; and D0.9—0.9 kg m−3. Experiment 2 used juveniles weighing 8.22 g at the following densities for 75 days: D0.8—0.8; D1.2—1.2; and D1.6—1.6 kg m−3. Experiment 3 used juveniles weighing 142.18 g at the following densities for 75 days: D2—2; D4—4 and D6—6 kg m−3. In Experiment 1, density did not influence performance (p > 0.05), with the exception of biomass, which was greatest in D0.9 (p < 0.05). In Experiment 2, final weight, weight gain and daily weight gain were highest for D0.8 (p < 0.05), as was triglycerides (p < 0.05), whereas biomass increased with increasing density (p < 0.05). In Experiment 3, weight, weight gain and daily weight gain were greater for D2 and D4 (p < 0.05), while final biomass was lowest for D2 (p < 0.05). Hemoglobin was lower for D4 and D6 (p < 0.05), while cholesterol and glucose levels were higher for D2 and D6 (p < 0.05). Colossoma macropomum demonstrated adaptive capacity for reared in RAS at high stocking densities. [ABSTRACT FROM AUTHOR]