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Keywords: BFT; FAPROTAX; IMTA; Litopenaeus vannamei; metagenomics; Oreochromis niloticus EN BFT FAPROTAX IMTA Litopenaeus vannamei metagenomics Oreochromis niloticus 5428 5433 6 09/21/22 20221015 NES 221015 Metagenomics allows for a comprehensive evaluation of the bacterial community in diverse habitats, as the whole collection of genomes in a sample is sequenced, instead of the conventional culture-based approach in which particular strains/species are isolated and cultured in a laboratory setting (Bodor et al., 2020; Wajid et al., 2021). Aquaculture Research, 49, 1699 - 1708. https://doi.org/10.1111/are.13626 56 Zhu, Y., Wang, S., Huang, L., Yan, M., Dong, P., Chen, C., Guo, H., & Zhang, D. (2021). Reviews in Aquaculture, 13 (2), 1077 - 1096. https://doi.org/10.1111/raq.12513 27 Johnson, M., Zaretskaya, I., Raytselis, Y., Merezhuk, Y., Mcginnis, S., & Madden, T. L. (2008). Reviews in Aquaculture, 11 (1), 234 - 245. https://doi.org/10.1111/raq.12237 38 Poli, M. A., Legarda, E. C., Lorenzo, M. A., Martins, M. A., & Vieira, F. N. (2019). [Extracted from the article]

The aim of this study was to investigate the effect on fish health indicators of different Nile tilapia (Oreochromis niloticus) stocking densities when reared in an integrated culture with Pacific white shrimp (Litopenaeus vannamei) using biofloc technology for 57 days. Three fish densities were evaluated: 8, 16 and 24 fish tank−1 with four replicates each. The experimental units comprised 800 L (useful volume) tanks for shrimp rearing and 90 L (useful volume) tanks for the culture of tilapia, which had an initial mean weight of 9.64 ± 0.14 g. A submerged pump located inside the shrimp tanks recirculated the water between the two units. The system was managed as a biofloc technology unit, with the addition of organic carbon to control ammonia and the monitoring of water quality, which remained within suitable ranges for both species. On day 57, fish were sampled for the assessment of the hemato-immunological variables. Fish reared under the highest stocking density exhibited significantly higher values of hematocrit and total leukocytes when compared to the two lowest densities (p < 0.05). The count of neutrophils and the agglutination titer were significantly greater in the 16 and 24 fish tank−1 groups (p < 0.05). These results suggest that, although the fish reared under the two stocking densities appear to have been undergoing physiological changes at the end of the culture period, the hemato-immunological alterations were not characterized by a general immunosuppressed state and instead by immunoenhancement. This is an indication that the carrying capacity of the system as regards fish density was being reached only towards the end of the trial. • The highest fish stocking density increased hematocrit and total leukocyte count. • The two highest densities resulted in higher neutrophil and agglutination titer. • Results suggest that fish were not characterized by general immunossupression. • Immunoenhancement seems to have occurred towards the end of the trial. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of the dietary supplementation of levamisole hydrochloride on Oreochromis niloticus lipid and protein profiles through matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) and possible tissue lesions by histopathological analyzes. A total of 320 fingerlings were distributed into the following groups: fish fed supplemented diets with 100, 150 and 200 mg of levamisole kg−1 and fish fed a diet receiving no supplementation. After 8 days of feeding, stomach histopathology showed that fish fed the 100 and 150 mg kg−1 levamisole supplemented diets had a significantly lower intensity in the degeneration of columnar epithelial cells when compared to the control group (p < 0.05), possibly a result of a generalized superior health status caused by the supplementation. Liver analysis showed no significant alterations (p ≥ 0.05), while histopathology of gills showed significant alterations in the fusion of secondary lamellae, in which only fish fed the highest dose showed a significant higher value when compared to the control group (p < 0.05). In the protein analysis, a total of 106 m/z peaks were observed, where 28 peaks showed significant changes in their intensity (p < 0.05). In general, fish supplemented with 100 mg kg−1 of levamisole showed an increase in the intensity in the peaks within the m/z ranges 2814–3337, 3732–6998 and 9045–13,505, while fish fed with 150 mg kg−1 dose showed a reduction in the intensity at most of the peaks found within those intervals. Immune system related proteins occurring within those ranges suggest a positive modulation of the protein profile. There were also marked alterations in the lipid profiles. Levamisole supplemented fish showed a significant positive modulation in the glycerophosphocholines group (p < 0.05), whose function in improving fish resistance to cold water suggests an additional health benefit of this feed additive. Judging on the histopathological analyses and MALDI-TOF MS lipid and protein profiling, the 100 mg kg−1 levamisole supplementation dose provided the greatest benefits to Nile tilapia fingerlings. • 100 and 150 mg kg−1 fed levamisole did not negatively affect Nile tilapia histology. • MALDI-TOF protein and lipid profiles were significantly altered by levamisole. • Glicerophosphocholin lipid peaks were positively modulated in levamisole fed fish. • 100 mg kg−1 levamisole supplementation provided the best benefits to Nile tilapia. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of heterotrophic and mature biofloc systems on yield, water quality, sludge production, water bacterial community, recovery of nutrients and fish health in Litopenaeus vannamei and Oreochromis niloticus integrated culture through a 53-day experiment. Two treatments were evaluated: an organic carbon (C) supplemented system (heterotrophic treatment), in which organic C was supplemented throughout the whole experiment and no biofloc inoculum was added at the beginning, and a mature treatment in which half of the volume of shrimp units was filled with biofloc-rich water from a previous rearing cycle before the culture started. Shrimp (3.34 ± 0.03 g) and fish (5.73 ± 0.06 g) were stocked at 300 shrimp m−3 and 344 fish m−3. The former were fed according to a feeding table, while the latter were fed at the rate of 1% of their biomass to stimulate the ingestion of bioflocs. Shrimp growth performance was unaffected (p >.05), but fish reared in the heterotrophic treatment exhibited better values for all growth performance variables evaluated (p <.05). Total ammonia nitrogen and nitrite were lower in the mature treatment (p <.05). Total sludge produced in the heterotrophic treatment was 114% higher than that in the mature treatment (p <.05), which resulted in greater sludge produced per animal biomass (sludge to biomass ratio) (p <.05). Bacterial community diversity was reduced in the heterotrophic treatment, and relative abundance of Vibrionaceae was reduced. The recovery of N and P was higher in the heterotrophic treatment (p <.05). Fish health was unaffected by the biofloc system. This research shows that the organic C supplemented system favored fish growth in the integrated rearing, maintaining water quality suitable for growing organisms and healthy fish. In contrast, the mature system produced less sludge. • Mature and heterotrophic biofloc systems were applied to Litopenaeus vannamei and Oreochromis niloticus integrated rearing. • The heterotrophic treatment resulted in an increased amount of sludge removed. • Shrimp yield was unaffected while the tilapia yield increased by 120% in the heterotrophic treatment. • N and P recoveries were greater in the heterotrophic treatment. • Bacterial community diversity and relative abundance of Vibrionaceae were reduced in the heterotrophic treatment. [ABSTRACT FROM AUTHOR]

Abstract This study aimed to evaluate the effect of different stocking densities of Nile tilapia, Oreochromis niloticus , integrated with Pacific white shrimp, Litopenaeus vannamei , reared in a biofloc system for 57 days. The performance of both species and the ecological efficiency of the system were evaluated. Four levels of tilapia stocking density were evaluated: 0, 8, 16 and 24 fish per tank (90 L useful volume). The initial weight was 4.8 ± 0.1 g and 9.6 ± 0.1 g for shrimp and fish, respectively. The shrimp were fed according to the feed table, and the fish were fed with 1% of fish biomass, stimulating the tilapia to seek food in the biofloc. Results show no difference between average shrimp weight (14.9 ± 0.6 g) and survival (93.0% ± 1.0%). Similarly, fish obtained a final mean weight of 61.9 ± 3.8 g and survival of 91.1 ± 7.9%. Total yield was higher based on the increase in fish density. The sludge produced per animal biomass (sludge:biomass ratio) decreased as fish density increased (y = − 0.0083xx + 0.5995 r2 = 0.87). Nitrogen recovery rose linearly with the increase in fish density (y = 0.036xx + 0.2725, r2 = 0.84), as did phosphorus recovery (y = 0.00711xx + 0.1395, r2 = 0.91). These results demonstrate the feasibility of increasing yield up to 31.2% by integrating L. vannamei and O. niloticus in a biofloc system. Also, the decrease in sludge:biomass ratio and the higher nitrogen and phosphorus recovery increased the sustainability of L. vannamei rearing in a biofloc system. Highlights • It was evaluated the integration of Litopenaeus vanammei and Oreochromis niloticus in the biofloc technology. • Shrimp was reared in 311 animals m−3 and the tilapia was reared with three different stock densities. • It was possible to increase productivity up to 31.2% • The recovery of nitrogen and phosphorus increased 27.9% and 223.0% respectively. [ABSTRACT FROM AUTHOR]