Biofilm-based aquaculture systems constitute a promising alternative for intensive shrimp rearing. Microorganisms forming biofilms can recycle the nitrogen compounds the production units improving the water quality while using zero or limited water exchange. This study aimed to compare the taxonomic profiles and the predicted functions related to the transformation of nitrogenous compounds between a heterotrophic- (HtB) and a probiotic biofilm (PrB), and the effect of these on the water quality and the productive response of cultured shrimp. Libraries of the 16S-rRNA gene (V3-V4 region) were prepared and sequenced to be used as a taxonomic biomarker. Analysis of metagenomic datasets revelated that genera Halomonas, Planctomycetes and Rhodopirellula were the most abundant genera in HtB; meanwhile, Bacillus, Halobacillus and Flavobacterium dominated in PrB. Regarding nitrogen metabolism, the proportion of genes encoding enzymes catalyzing the six pathways shaping the nitrogen metabolism showed differences between biofilms, which could also explain the difference in water quality between treatments. Concerning the productive response of shrimp, no significant differences were detected except for survival, which was higher in PrB. Finally, the results suggest that biofilms harbour functions for nitrogen metabolism, including dissimilatory nitrate reduction, assimilatory nitrate reduction, denitrification, nitrification, nitrogen fixation and anammox; however, the balance of these functional capabilities seems to be relevant to maintain water quality.
Bibliographical noteFunding Information:
This research (grant 222722) and a Ph.D. fellowship to the first author (AMOE) were financially supported by the Mexican Government through the National Council of Science and Technology (CONACyT). The technical assistance from MS José Luis Niebla‐Larreta during the experimental trial is acknowledged. Thanks are also to MS Estefania Garibay‐Valdéz and BS Silvia Cristina Valdéz‐Verduzco for their contributions during the trial.
This research (grant 222722) and a Ph.D. fellowship to the first author (AMOE) were financially supported by the Mexican Government through the National Council of Science and Technology (CONACyT). The technical assistance from MS Jos? Luis Niebla-Larreta during the experimental trial is acknowledged. Thanks are also to MS Estefania Garibay-Vald?z and BS Silvia Cristina Vald?z-Verduzco for their contributions during the trial.
© 2020 John Wiley & Sons Ltd
- Lito penaeus vannamei
- bacterial communities
- heterotrophic biofilm
- predictive nitrogen metabolism
- probiotic biofilm
- super-intensive indoor farming