Intensification of the Giant river prawn Macrobrachium rosenbergii hatchery production

We evaluated the effect of intensification on Macrobrachium rosenbergii hatchery in clear water recirculating system. Larvae were raised in 120-L cylindrical tanks coupled with 30-L biofilters. We performed two experiments in randomized blocks. In the first, we tested the stocking densities of 50, 70 and 90 newly hatched larvae L-1. Survival did not differ by ANOVA (P = 0.343), but productivity increased with the intensification (P = 0.038). In the second experiment, we tested the stocking densities of 80, 100, 120 and 140 newly hatched larvae L-1. Survival decreased (P = 0.039) as density increased, but productivity did not differ (P = 0.317). The period of culture ranged from 22 to 23 days. The intensification did not influence water quality parameters or larval development. Survival decreased with the intensification and the space showed to be a limiting factor on tanks stocked with 90 larvae L-1 or more. Productivity curve shows an increase from 50 to 100 larvae L-1 and tended to reach plateau on stocking densities higher than 100 larvae L-1. In addition, the intensification improved the use of Artemia cysts by decreasing the superfluous feeding. Thus, we recommend stocking of 80 to 100 newly hatched larvae L-1 as the best option for M. rosenbergii hatchery in clear water recirculating system.