Effect of Density at Harvest on the Growth Performance and Profitability of Hatchery-reared Spotted Rose Snapper, Lutjanus guttatus, Cultured in Floating Net Cages

摘要

This study evaluated the effect of the density at harvest on the performance and profitability of hatchery-reared spotted rose snapper cultured in cages. The fish were stocked at harvest densities of 15, 20, and 22kg/m(3) in cages of 222 and 286m(3). More than 39,000 snapper fingerlings with an initial weight of 14g were stocked. The fish were fed an extruded diet and cultured over a 360d period. The thermal growth coefficient ranged from 0.04 to 0.05 and survival was 95% for all treatments, with the highest final weight (436.8g) observed for fish reared at a density of 20kg/m(3). The allometric value b indicated that hatchery-raised, cage-cultured snapper were heavier than their wild counterparts. The major costs were feed (ranging from 44.7-45.9%), labor (22.4-32.6%), and seed costs (20.2-26.1%). The total production cost ranged from US$ 6.5 to US$ 7.5/kg. The baseline scenario was not economically feasible. However, a 10% increase in the sales price resulted in increases in the internal rate of return (183%) and net present value (US$ 97,628.9). These results suggest that L. guttatus has the potential for commercial production in cages.