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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.

This work aimed to evaluate growth performance, gut histology, digestive enzyme activity and resistance to challenge with White Spot Syndrome Virus (WSSV) of Litopenaeus vannamei fed 0.5, 2 and 4% of dry biomass from the brown seaweeds Sargassum filipendula and Undaria pinnatifida. Shrimp (4.23 ± 0.15 g) were reared for 38 days in 800 L tanks (40 animals per tank) in triplicate under constant aeration (O2 > 5 mg L−1), controlled temperature (29.06 ± 0.32 °C) and 100% daily water exchange (static). Animals were fed five times per day, and the amount of feed was calculated in accordance with a pre-established feed conversion rate method. To estimate survival and growth, all animals from each tank were weighed and counted every week. At the end of the experiment, the hepatopancreas from each of six shrimp per treatment was collected to assess the digestive enzymes, and the anterior abdominal segment from each of four shrimp per treatment was isolated to evaluate the gut histology. For WSSV challenge, 40 animals per treatment were infected and kept for 72 h to determine mortality. Growth performance was not affected by seaweed addition in the diet. However, the lowest level of both seaweeds increased shrimp gut epithelial surface for nutrient absorption, and all levels of S. filipendula and 4% of U. pinnatifida increased amylase activity, while lipase activity was only stimulated by 4% of U. pinnatifida. Proteolytic enzymes were not affected by the addition of dietary seaweed. Additionally, 4% of U. pinnatifida resulted in lower mortality after WSSV challenge (48%) compared to control (74%). Therefore, seaweed addition improved shrimp digestive capacity and resistance to WSSV challenge, but without impairing growth performance.

In order to reduce disease outbreaks in shrimp aquaculture, biosafe farming practices have been created, such as the biofloc system and the use of feed additives to improve shrimp immune response and growth performance. Many studies with feed additives have tested probiotics in biofloc rearing systems; yet to date, no studies have reported on the use of prebiotics in the feed of farmed shrimp in biofloc systems. Moreover, the effects of mannoprotein (MP) prebiotics on shrimp and shrimp farming are also unknown. Therefore, this study aimed to evaluate the effects of dietary supplementation with mannoproteins (MP) on the performance, immune response, and midgut intestinal villi of L. vannamei raised in a biofloc system. Three diets with different MP concentrations were formulated (0.02%; 0.08%; 0.12%) and one control group without MP additive. The experiment utilized 12 experimental units (800 L) stocked with 400 shrimp/m3, with 3.64 ± 0.07 g of initial weight, in triplicate. Shrimp were fed four times per day, and both histology of the midgut and growth indices were assessed after 65 days. Intestinal villi presented a larger internal surface area in animals that were fed dietary supplements of 0.08% and 0.12% MP (p

Pacific white shrimp, Litopenaeus vannamei, is a tropical species known to be intolerant to cold. In our earlier work, increased thermal shock resistance caused by Sargassum filipendula raised unanswered questions about the mechanisms responsible for this resistance. Therefore, in the present work, we used MALDI-TOF mass spectrometry (MS) to assess protein and lipid profiles of intact and lysed hemocytes from Pacific white shrimp fed 0.5% of S. filipendula and submitted to thermal shock. To accomplish this, shrimp (13.0 ± 0.4 g) were reared during 15 days in 800 L tanks (35 shrimps tank− 1), in duplicate, under constant aeration and temperature (28.5 °C), 100% of daily water exchange and feeding four times day− 1. At day 16, animals were submitted to thermal shock by passing from seawater at 28.5 °C to 11.5 °C, where they remained for 1 h, and then returning to 28.5 °C. Mortality was monitored during 24 h. Hemolymph of 10 animals per treatment (control and 0.5% S. filipendula) was collected before and 15 min after thermal shock for MALDI-TOF MS analyses. Hemocytes were processed in both intact and lysed cells. Samples were mixed (1:1) with 2,5-dihydroxy-benzoic acid matrix for lipid analysis and sinapinic acid for protein. Shrimp fed 0.5% S. filipendula showed higher signal intensity of phosphatidylcholines with unsaturated fatty acids and lower signal intensity of lysophosphatidylcholines, after thermal shock. For proteins, S. filipendula increased signals that could be associated with antimicrobial peptides and histone H2A, whereas reduced signals were related to Cytochrome c oxidase subunits. Based on these results, it can be concluded that S. filipendula increased membrane fluidity and antimicrobial defense, diminished apoptotic signaling, and modulated DNA regulation, lipid and energy metabolism of shrimp hemocytes. These mechanisms could explain, at least in part, the higher thermal shock resistance of these shrimp fed a diet with 0.5% S. filipendula.

Mealworm meal (MM) was evaluated for its potential as a future protein source for the farmed shrimp Litopenaeus vannamei . The apparent digestibility coefficients (ADC) were determined using a reference diet and a test diet that contained 85% reference diet and 15% MM, both contained 0.5% chromic oxide as an inert marker. Subsequently, considering the digestible values of MM, after six weeks of culture under clear water using five diets containing different levels of fishmeal replaced by MM (0%, 25%, 50%, 75% and 100%), the growth parameters and the whole shrimp body composition were evaluated. The values of the ADC were: 45.9% for dry matter, 66.5% for energy and 76.1% for crude protein while the ADC for essential amino acids ranged from 72% to 86%. Methionine was the first limiting amino acid in MM. Weight gain, specific growth rate, feed intake, feed conversion, survival and protein retention were not affected when fishmeal was replaced by MM (P > 0.05). The protein content of the shrimp body showed no significant differences (P > 0.05) between the treatments. However, lipid content of the shrimp body increased from 1.13% to 1.88% when fishmeal was replaced by MM. These results suggest that mealworm meal can be utilized as an alternative protein source for L. vannamei juveniles, although methionine should be added as a supplement.

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

This work aimed to evaluate the effects of integrated culture of sea lettuce (Ulva fasciata) on the shrimp (Litopenaeus vannamei) and mullet (Mugil liza) rearing in a biofloc technology (BFT), on water quality, animal performance and seaweed growth, nitrogen and phosphorus recovery, seaweed bioactive compounds. Two groups were compared: i) Ulva group: cultivation system integrating shrimp and mullet with seaweed, ii) control group: the same without seaweed, both groups used BFT. Each group had four replicates; initial biomass was 618 ± 8 g and 246 ± 34 g for the shrimp and mullet, respectively. Additionally, in the Ulva group, 120 g of sea lettuce per tank was included every two weeks. After 55 days, the integration of seaweed in the system did not influence the shrimp and mullet performance. Shrimps grew, on average, 1.22 g week−1, with 90.6% survival, 2.91 kg m−3 yield and 1.84 FCR. Mullets grew, on average, 1.035 g week−1, with 99.17% survival, and 4.08 kg m−3 yield. At the end 317.01 ± 32.02 g of seaweed per experimental unit was harvested. The total final biomass and yield, considering the whole system, were 12.2% higher in the Ulva group than in the control group. Nitrogen and phosphorus recovery were respectively 5.5% and 7.6% higher in the Ulva group than in the control group. The nitrogen, phosphorus, chlorophyll-a and carotenoids contents in the Ulva group were also higher at the end of the experiment. In conclusion, the integration of sea lettuce can increase the total yield, nitrogen and phosphorus recovery in the biofloc system. Furthermore, the integration of sea lettuce in this system can increase the content of chlorophyll-a and carotenoids, without affecting the yield of ulvan extract.

The present work aimed to evaluate the effects of different levels of Ulva fasciata obtained from an Integration Multi-Trophic Aquaculture (IMTA) culture and added at different levels (0, 5, 10, and 20 g kg−1) to formulated isoproteic and isolipidic diets (45% crude protein and 12.5% crude fat) for Seriola dorsalis on growth, hematology, and fatty acid profile content in muscle tissue. One hundred and twenty juveniles (7.93 ± 0.24 g) were randomly distributed into 12, 500 L tanks connected to a recirculating system (four treatments in triplicate groups). After 48 days that fish were fed at 5% of the initial fish biomass, no effects on growth performance and somatic parameters were found. However, concerning the hematological parameters, the hematocrit showed statistical differences among the treatments, being higher in fish fed the U-20 diet than the control (U-0). Moreover, U. fasciata supplementation at 10 g kg−1 resulted in a decrease of approximately 20% in linoleic acid and an increase of approximately 49% in DHA of muscle tissue, most likely associated with LC-PUFA sparing effect. Therefore, the addition of U. fasciata from IMTA culture improves the fish muscle tissue quality.

This work aimed to evaluate three different strategies for rearing L. vannamei in a biofloc system: heterotrophic, chemoautotrophic and a mature biofloc system relative to the effects of water quality, water bacterial community, biofloc composition and yield. To accomplish this, a study lasting 35 days was conducted with juvenile (3.46 g) shrimps stocked in twelve 300 L tanks at a stocking density of 350 shrimp m3. For heterotrophic treatment, water received molasses as a carbon source. For chemoautotrophic treatment, ammonium and nitrite salts were added to the water. The mature treatment was created by adding a significant amount of water containing mature biofloc from another established biofloc technology (BFT) system. In both mature and chemoautotrophic treatments, the nitrification process could maintain toxic nitrogen compounds (ammonia and nitrite) at low levels without the addition of carbohydrates. In contrast, the heterotrophic system had peaks of ammonia and nitrite during the rearing cycle. The heterotrophic system also had a significantly higher value of volatile solids and total suspended solids compared to the other treatments. Analysis of the biofloc system revealed a relatively high proportion of protein, but the proportion of protein in the heterotrophic system was higher. Chemoautotrophic and mature treatments maintained the water quality at a constant level, especially nitrogen removal. Metagenomic analysis showed the microbial community associated with the biofloc system to be represented by 10 phyla. In all treatments, the five most abundant phyla were the following: Proteobacteria, Bacteroidetes, Chloroflexi, Actinobacteria, and Gemmatimonadetes. Shrimp performance demonstrated that heterotrophic, mature and chemoautotrophic systems are suitable approaches for shrimp rearing in BFT.

The objective of this study was to isolate and identify bacteria of the genus Bacillus sp. from a super-intensive culture system with Litopenaeus vannamei microbial flakes, and evaluate their potential of affecting the water quality, performance and immunological parameters when added to the water and diet. Bacillus spp. isolates were evaluated in vitro for the ability to inhibit pathogens, antagonistic activity. After selection, Bacillus spp. was added to the water to assess the influence in the formation and maintenance of microbial flakes in post-larvae culture. In order to verify the performance and hemato-immunological parameters of L. vannamei for 42 days of culture, they were incorporated in formulated diets. Four bacteria were isolated from the microbial flakes super-intensive system: Bacillus thuringiensis CPQBA 571-12 DRM 06 (> 99%), Bacillus licheniformis CPQBA 571-12 DRM 07 (> 99%), B. licheniformis CPQBA 571-12 DRM 08 (> 99%) and Bacillus cereus CPQBA 571-12 DRM 09 (> 99%). B. licheniformis CPQBA 571-12 DRM 07 was the only isolate that showed in vitro inhibitory characteristics against the pathogen Vibrio alginolyticus (BCCM 2068) with a 20 mm diameter inhibition zone and the isolates did not show any antagonistic activity. For the test of formation and maintenance of microbial aggregates generated in the post-larvae culture super-intensive system, a significant difference was observed (p Statement of relevance Bacillus spp. were isolated from biofloc system water and can be supplemented in shrimp (L. vannamei) feed to increase immunocompetence and used as biocontrol for Vibrio spp. in water.

This study aimed to evaluate the relationship between salinity in the performance of marine shrimp Litopenaeus vannamei and halophyte plant Sarcocornia ambigua in an aquaponic system with biofloc. The experiment was conducted for 57 days, and four treatments were evaluated: 8 psu (practical salinity unity), 16 psu, 24 psu, and 32 psu, with three replicates. Each experimental unit consisted of an 800 L tank for shrimp rearing, a 40 L settling chamber and a hydroponic bench of 0.3 m2 of planting area and density of 40 plants m−2. The tank water was continuously pumped to the settling chamber, and the supernatant was distributed on the hydroponic bench to irrigate the plants, returning to the tank by gravity. The tanks were stocked with 300 shrimp m−3 (1.6 ± 0.1 g). The shrimp were fed four times daily with a commercial diet containing 38% crude protein. Salinity affected shrimp survival, which was lower in 8 psu treatment (56.3 ± 4.7%). No salinity relationships were detected with any of the plant performance parameters; however, the highest biomass was produced at 16 psu, which is close to the isosmotic point of S. ambigua. The lowest concentrations of ammonia and nitrite and the highest concentrations of nitrate were found, through the interpolation of the data, near the 18 psu salinity. So, it is suggested that in this salinity, the absorption of ammonia by the plants is favored. The salinity also affected the concentration of dissolved orthophosphate. There was no relationship between salinity and the production of phenolic compounds and antioxidant activity in plants. The integrated cultivation of L. vannamei with S. ambigua can be carried out between salinities of 16 and 24 psu since the performance of the shrimp is not impaired, and the growth of the plants and the removal of nitrogen and phosphate compounds are favored in this range of salinity.

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

The aims of this research were to evaluate the zootechnical performance and dietary cost for the marine shrimp ( Litopenaeus vannamei ) cultured in a superintensive biofloc system and a conventional semi-intensive system using diets containing different protein levels. Four different diets, with crude protein (CP) contents of 24.3, 30.3, 32.9 and 36.7% were produced. In the laboratory, experimental culture in the biofloc system was performed in twelve experimental units at a density of 250 shrimp m − 3 , the four treatments were performed in triplicate. The semi-intensive culture system was applied at the commercial farm in eleven ponds containing 15.5 shrimp m − 2 . After 49 days, the zootechnical performance of the shrimp was rated, and the cost per kilogram of shrimp was produced by both culture systems. In the semi-intensive system, the shrimp fed with a diet containing 32.9% CP showed a higher final weight and weight gain and a lower dietary cost. In the biofloc culture, a higher final weight, weight gain, growth rate and productivity were observed in shrimp fed diets containing 30.3, 32.9 and 36.7% CP compared with those fed a diet containing 24.3% CP. The lowest dietary cost of shrimp farming in the biofloc system was registered in the shrimp fed the 30.3% CP diet, whereas, in the semi-intensive system, the highest final weight, highest weight gain and lowest cost were observed in shrimp fed the 32.9% CP diet.

We evaluated an integrated system for rearing Pacific white shrimp (Litopenaeus vannamei) and white mullet (Mugil curema) in an experimental-scale biofloc system. Performance of the animals, water quality, phosphorus and nitrogen retention and mass balance, and fish hematology and immunology were compared among two treatments: 1) shrimp with mullet integrated system (Shrimp + Mullet), and ii) shrimp without mullet system (Shrimp). A tank with 800 L of useful volume was used to rear the shrimp with a density of 250 shrimp m−3. Another tank with 90 L of useful volume was maintained for rearing fish (15 mullet tank−1) in the Shrimp + Mullet treatment. The shrimp treatment also used the 90-L tanks, but without the fish. Water was recirculated into the mullet tanks via a submerged pump and returned by gravity to the shrimp tanks. The shrimp were fed four times a day. A feeding table was used to adjust the amount of feed provided, and the fish were fed only once daily with a ratio of 1% initial biomass to stimulate biofloc consumption (BFT). After 53 days, shrimp growth (final weight 12.56 ± 0.22 g) and survival (91.8% ± 2.9%) were similar between treatments. Fish had adequate survival (91.1% ± 10.2%), and adequate growth for Mugil species (0.71 ± 0.05 g week−1) in the integrated system. In the Shrimp + Mullet treatment, animal productivity was increased by 11.9% by combining Shrimp + Mullet biomass, when compared to the Shrimp treatment. The Shrimp + Mullet treatment also demonstrated a 16.8% increase in phosphorus retention compared to the Shrimp treatment. The hemato-immunological parameters showed that fish kept in a biofloc system had adequate values comparable to those reported for Mugil species. Thus, these experimental-scale results demonstrate that the integration of shrimp and mullet in biofloc systems increases yield and phosphorous retention without compromising fish health and shrimp growth. In addition, we recommend reproducing this integrated system over a longer period and at commercial-scale, supporting an economic analysis.

This study aimed to evaluate the performance of an integrated multitrophic aquaculture (IMTA) system applied to shrimp rearing in biofloc technology (BFT). The IMTA system consisted of shrimp (Litopenaeus vannamei) in a rearing tank (800 L), a tilapia (Oreochromis niloticus) rearing tank (90 L), and a hydroponic bench with 0.33 m2 of planting space for Sarcocornia ambigua culture. A submerged pump constantly pumped water from the shrimp tank to the tilapia tank. Then, by gravity, water flowed through the sarcocornia hydroponic bench and returned to the shrimp tank. The hydroponic bench had enough capacity for 32 plants. Shrimp, tilapia and sarcocornia stock densities were 312 shrimp m−3 (250 shrimps per 800 L tank), 445 tilapia m−3 (40 tilapias per 90 L tank), and 97 sarcocornia plants m−2 (32 plant per system), respectively. The same experimental units were used in the control system which only differed by the absence of sarcocornia. The initial weight was 4.09 ± 0.025 g, 1.16 ± 0.02 g and 1.17 ± 0.175 g for shrimp, fish and sarcocornia, respectively. Shrimps were fed according to the feed table, and the fishes were fed with 1% of fish biomass, stimulating tilapia to use biofloc as a food source. Results show no difference between shrimp and tilapia performance in either treatment. Only IMTA total yield (4.83 ± 0.19 kg m−3) was significantly higher than that in the control system (3.99 ± 0.045 kg m−3). Nitrate was higher in the control system (12.28 ± 1.27 mg L−1) compared to the IMTA system (9.38 ± 1.09 mg L−1).These results demonstrate a yield increase of up to 21.5% by multitrophic integration of L. vannamei, O. niloticus and S. ambigua in a biofloc system.

Organic acids or their salts can be used as growth promoters in aquaculture, aiding in pathogen inhibition in the intestinal tract, providing energy to aquatic organisms, and improving the digestibility of dietary nutrients, such as nitrogen and phosphorus. The objective of the present study was to select salts of organic acid such as sodium acetate, sodium butyrate, sodium citrate, sodium formate, sodium lactate and sodium propionate, with potential to be used as feed additives for marine shrimp. One performed and analyzed in vitro inhibition of three Vibrio species ( Vibrio harveyi , V . alginolyticus , and V . anguillarum ), at two different pH values (6.2 and 7.1). The attractiveness of the diets was assessed by the percentage of positive choices and rejection, in aquariums, of dual choice Y-maze format. The leaching of different salts in the diets was also evaluated after immersion in seawater for 0, 15, 30, 45 and 60 min. In order to evaluate the intestinal bacterial count alteration, shrimps were fed, during 14 days, with diets containing 2% of their salts plus a control diet. Later, it was possible to determine the bacteriological count of total heterotrophic marine bacteria (Marine Agar) vibrio species (TCBS Agar) and bacteria lactic acid (MRS Agar). Subsequently, data of bacterial inhibition in vitro and in vivo , besides the tests of attractiveness and leaching of diets were used to select the best salts by the ideotype test through Mahalanobis distance. After, the top three salts were used in the tests of feed intake and digestibility of dry matter, protein, energy and phosphorus. The results of this study clearly indicate that salts of organic acids possess inhibitory activity against pathogenic vibrio species in marine shrimp, with propionate, butyrate, and acetate salts exhibiting the highest inhibitory capacity (p Litopenaeus vannamei , besides increasing the apparent digestibility of energy (p L . vannamei .