Bacillus Subtilis na criação de Tambaqui em Sistema de Bioflocos

Abstract

Closed aquaculture systems can be enriched with probiotics such as Bacillus subtilis to promote a sustainable fish farming. In this study, we focused on the effect of B. subtilis on a clear water static system compared with a system based biofloc technology (BFT). Tambaqui juveniles were assigned to one of the four treatments, each of which was replicated five times: clear water static system with (CW+BS) or without (CW) B. subtilis, and BFT with (BFT+BS) or without (BFT) B. subtilis. Each replicate group comprised 20 tambaqui juveniles in an artificially aerated 200-L tank. For B. subtilis treatments, tanks were inoculated at weekly intervals with a 4 × 108 cell mL-1culture suspension. All fish were fed (2% of the estimated biomass) three times a day for 62 days. All water parameters of the BFT were within the recommended limits for tambaqui farming. Although there was no interaction between the factors for zootechnical performance, fish raised in the BFT system were 50% heavier than those in the CW system, which was attributable to biofloc consumption. Despite theinoculation with B. subtilis did not improve tambaqui growth, BFT is a promising technology that can be used to save water, decrease aquaculture effluents, and promote tambaqui farming.