Aquaculture Reports (Nov 2020)
A new efficient method for the mass production of juvenile spotted rose snapper Lutjanus guttatus
Abstract
The present technical note reports the new method for the mass production of spotted rose snapper Lutjanus guttatus juveniles. The source of eggs came from a total of 387 spawns obtained in 2013 and 2014. 85 % of the spawns had floating eggs, and 93.5 ± 2.8 % of them had live embryos. The initial stocking density of eggs in the rearing tanks was 165 ± 69 embryos/l. The hatching rate was 88 ± 4%, with 50 ± 8% larval survival at 48 h post-hatch (hph). After 35 days post-hatch (dph), a total of 706,799 pre-juveniles (0.1 ± 0.05 g of body weight) were harvested, obtaining from first feeding 31 ± 20 % larval survival. The larvae grew from an average of 2.55 mm–23.58 mm in five weeks. From nursery I, a total of 664,301 juveniles with 0.6 g to 0.8 g body weight (BW) were harvested (94 % survival) and transferred to nursery II, growing on average from 0.48 g to 14.78 g BW in seven weeks. Finally, from nursery II a total of 596,382 juveniles (5–15 g BW) were harvested at 90 dph (89.8 % survival) and delivered to farmers for grow-out. The new method was integrated with an older rearing protocol, and a pre-commercial number of juveniles was produced with high efficiency, requiring only four 48 hph larvae to produce every 90 dph juvenile. These results provided an improvement in the state-of-the-art of snapper aquaculture and it can be applied at a commercial scale.