Effect of biofloc technology (BFT) on the early postlarval stage of pink shrimp Farfantepenaeus paulensis: growth performance, floc composition and salinity stress tolerance

Abstract

Biofloc rearing media provides a potential food source for shrimp reared in limited or zero water exchange systems. This culture system is environmentally friendly as it is based on limited water use and minimal effluent is released into the surrounding environment. In this study, we evaluated the survival, growth performance and salinity stress tolerance of pink shrimp Farfantepenaeus paulensis postlarvae reared from PL10 to PL25 in a biofloc technology limited water exchange system. PL (mean ± SD weight and length of 14 ± 10 mg and 8.10 ± 0.7 mm, respectively) were reared in nine 40-L plastic tanks with a stocking density of 10PL/L. Three culture treatments were applied (1) culture in the presence of bioflocs and commercial feed supply (FLOC ? CF); (2) culture in the presence of biofloc without feed supply (FLOC) and (3) culture in clear water with feed supply (control). Final biomass and survival were significantly higher in FLOC ? CF treatment than the control (P \ 0.05), but did not differ from FLOC. PL reared in the FLOC ? CF treatment achieved a significantly higher final weight, weight gain and length in comparison with the other two treatments (P \ 0.05). No significant difference(P [ 0.05) between treatments was found for salinity tolerance over 24 and 48 h durations. The proximate analysis of floc shown high levels of crude protein (30.4%), but low levels of crude lipids (0.5%). The continuous availability of bioflocs had a significant effect on growth and survival of F. paulensis postlarvae cultured in BFT nursery systems.