Oxygen consumption rates of spotted rose snapper Lutjanus guttatus (Perciformes: Lutjanidae) during larval development

Oxygen consumption of different larval stages of the spotted rose snapper Lutjanus guttatus were evaluated to help design food strategies for its culture. Oxygen consumption was determined using closed respirometers at a constant temperature of 30 degrees C in a thermoregulated bath. Six replicates and 2 control for each treatment were used. Larval stages were evaluated from 2 to 35 days after hatching (DDE). Dissolved oxygen was measured using a fiber-optic microsensor connected to an oximeter. Respiration was expressed in microliters of oxygen per milligram of dry biomass per hour (mu LO2 mg(-1)Bs h(-1)). Results indicate that oxygen consumption rate (R) decreased with the age of the larvae. Higher oxygen consumption was observed in the first 5 DDE which coincides with the onset of exogenous feeding. At 14, 19 and 30 DDE respiration rates showed slight increases and appear to be associated with morphological changes of the larvae (preflexion, flexion and postflexion, respectively). The values of the exponents of the potential allometric relationship between the specific biomass respiration rate and for each individual, based on the dry biomass of the spotted rose snapper were -0.172 and 0.834 respectively. The data obtained are important to estimate oxygen demand during the larval rearing of the spotted rose snapper, and combined with nitrogen losses can be used to estimate feeding requirements based on energy losses.