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This study evaluated the effect of biofloc technology (BFT) at 3 (lsBFT) and 35 (hsBFT) practice salinity units (psu) on the zootechnical performance, oxygen consumption, antioxidant activity, and oxidative damage of Litopenaeus setiferus juveniles reared in outdoor tanks. After 90 days, no significant differences were observed in terms of survival (p >.05). The final weight as well as wet weight gain, final biomass, and feeding conversion ratio (FCR) showed higher values for shrimp reared with hsBFT than those reared with lsBFT (p <.05). Compared to that for the hsBFT treatment, high oxygen consumption (VO2) was observed for the lsBFT treatment under fasting and postprandial conditions (p <.05). The activity of the enzymes catalase, superoxide dismutase, and glutathione‐S‐transferase from shrimp muscle did not show significant differences between the treatments (p >.05). Regarding the lipid peroxidation (LPO) and oxidized protein (PO) in muscle samples, no significant differences were observed in LPO, whereas the PO was significantly higher for the lsBFT treatment (p <.05), which was related to higher fasting and postprandial oxygen consumption of the juveniles (p <.05). The adaptation of L. setiferus juveniles reared in BFT at low salinity is relatively weak because of their low growth and excessive oxygen consumption and the oxidative damage (PO) produced. [ABSTRACT FROM AUTHOR]

In a 45‐d experiment, Litopenaeus vannamei was cultured in two treatments, biofloc technology or clear water recirculating aquaculture system, to evaluate the effect on growth and survival, energy balance, and texture of the marketable product. The experimental design consisted of 40 plastic tanks of 54 L (20 tanks per treatment), with a density of 140 organisms/m3 in each culture system. The final body weight, daily growth coefficient, and survival were significantly higher (P < 0.05) in biofloc technology (12.40 g, 5.0%g/d, and 87.1%, respectively) than in the clear water system (7.0 g, 1.4%g/d, and 74.2%). The retained energy and energy content of exuviae were significantly higher for shrimp in the biofloc technology (448.5 ± 36.4 and 22.4 ± 1.8 J/shrimp/d, respectively) than in clear water (246.3 ± 40.9 and 12.3 ± 2.0 J/shrimp/d, respectively). Routine metabolism was significantly higher for the clear water treatment (411.4 ± 123.8 J/shrimp/d). Shear force was higher in the biofloc technology, indicating greater muscle firmness; this matched the gel electrophoresis patterns of the proteins extracted from the muscle tissues. This suggests that biofloc technology could be used not only to improve growth and survival in L. vannamei but also to enhance the final product quality and acceptability in the market. [ABSTRACT FROM AUTHOR]

Abstract: The relative contributions of feed sources were determined through the isotopic signal (δ13C and δ15N) and fatty acid profile of feed items, shrimp muscle, and eggs of Litopenaeus vannamei reared in a biofloc system. In the growout phase, the isotope analysis showed the biofloc particle size class ≥250 μm contributed 55–100%; size ≥50 < 250 μm contributed 0–22%; and artificial feed contributed 0–45%. Principal component analysis applied to fatty acid profiles showed that biofloc ≥250 μm and artificial feed were the most important items in shrimp growout. For the egg production, isotope analysis suggested that the most important feed sources according to their relative contributions were polychaetes (0–100%), followed by artemia biomass (0–86%) and semi‐moist feed (0–66%), with lower contributions from squid, mussel, and the muscle of L. vannamei broodstock that had been cultured in biofloc. In terms of fatty acids, the most important items were artemia, polychaetes, and semi‐moist feeds. This work clarified the importance of feed sources for shrimp during culture in biofloc systems and during reproduction. Analysis of stable isotopes and fatty acids can be successfully used to trace the assimilation of nutrients during the nutrition of shrimp. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to use the natural dietary markers (stable isotopes and fatty acids) during grow‐out in a biofloc system and for the egg production of Farfantepenaeus brasiliensis shrimp. Egg production was compared for two broodstock origins: biofloc and a wild origin. To delineate the relative contribution to shrimp muscle and eggs, IsoSource software was used. The most important source that contributed to grow‐out shrimp was biofloc ≥250 μm. According to the principal component analysis (PCA) applied to the fatty acid profile of food sources, the first component explains 84.4% of the variability, and the most important source of fatty acids for this component was biofloc ≥250 μm. The most important fresh food sources that contributed to egg production were Artemia biomass, polychaetes and semi‐moist feed for both broodstock origins. According to a PCA analysis of the fatty acid profiles, the most important fresh foods were polychaetes and semi‐moist feed. In conclusion, both isotopic signature and fatty acid profile of the food sources can be used successfully to determine the integration of carbon in the diets of shrimp. [ABSTRACT FROM AUTHOR]

A 45-day trial was performed to evaluate the effect of biofloc technology ( BFT) with or without fresh food ( FF) supplementation during pre-maturation period on Farfantepenaeus duorarum spawning performance, biochemical composition and fatty acid profile of eggs as compared with conventional clear-water system ( CW+ FF). Females raised in biofloc and that received FF supplementation ( FLOC+ FF) achieved better spawning performance in terms of number of eggs per spawn (49 × 103), number of eggs per spawn per g of spawner's body weight (2.1 × 103) and egg size (~275 μm) as compared with CW+ FF (23 × 103, 1.1 × 103 and 263 μm respectively), but both treatments did not vary from FLOC ( P > 0.05). High spawning activity was also observed in biofloc system as compared with clear-water system as shown in number of spawns per ablated female (2.2-3.0 versus 0.6) and percentage of females that spawn at least once (80-82 versus 25%). Biochemical composition of eggs presented no significant differences among treatments. FA profile of eggs indicated that high spawning activity performed by females in FLOC+ FF treatment was reflected in lower mean levels of EPA, DHA and sum of polyunsaturated fatty acids (n-3) and (n-6). The better reproductive performance demonstrated by females raised in biofloc justified the application of this technology in F. duorarum broodstock. [ABSTRACT FROM AUTHOR]

The effect of biofloc (BFT) and clear water (CW) at low (ls) and high-water salinity (hs) in wild juveniles of Penaeus setiferus were evaluated. Four treatments were implemented: hsBFT, lsBFT, hsCW, and lsCW. After 45 days, final weight (FW), weight gain (WG), hepatosomatic index (HSI), and survival rate (SR) were evaluated. Antioxidant activity in muscle and hepatopancreas were measured: superoxide dismutase (SOD), catalase (CAT), glutathione-S transferase (GST), lipid peroxidation (LPO), protein oxidation (PO). The FW and SR was low for lsCW (P < 0.05), whereas the WG and HSI was high in hsBFT and lsBFT (P < 0.05). The integrative biomarker response index (IBR) showed differences between muscle (M) and hepatopancreas (HP). Results showed an increase of SOD and CAT measured from HP for lsBFT treatment. For M, CAT and GST were high only in BFT (regardless of the water salinity). LPO determined from M and HP recorded the high values at hs and ls, respectively. The PO determined in HP showed substantial damage in BFT (regardless of the salinity), whereas the same determination from M was only important for lsCW treatment. When the analyses of variance (ANOVA) were performed, SOD, LPO, and PO were significant in response to salinity (P < 0.05). In contrast, for CAT, the higher activity was due to the rearing system and salinity interaction (P < 0.05). Results suggest that BFT could diminish the stress by stimulating the antioxidant system to maintain the redox balance through a higher enzyme activity and decrease damage in the proteins and lipids of the cells. [ABSTRACT FROM AUTHOR]

• Shrimp origin and ablation drive both the reproductive performance and egg quality. • Egg biochemical reserves reflects the composition of the female hepatopáncreas. • Non-ablated females from biofloc origin had the best egg quality. The aim of this study was to evaluate egg production and quality of females of the Pacific white shrimp, Litopenaeus vannamei, in which there was or was not unilateral eyestalk ablation after there was pre-maturation culturing in biofloc or clear-water systems. Acylglycerides, cholesterol, glucose and total soluble protein were determined for the hepatopancreas, ovaries, hemolymph and eggs. Females cultured using the biofloc system had a larger number of eggs released per spawning and per gram of spawning specimen body weight. The number of total spawning's per week was comparable among treatments. Females cultured in the biofloc system in which there was no eyestalk ablation had that greatest concentrations of nutrient reserves in the hepatopancreas (P < 0.05) with the females cultured in the biofloc and clear-water system that had eye stalk ablation having the next most abundant nutrient reserves. There were the least concentrations of nutrient reserves in females with eyestalk ablation cultured in the clear-water system (P < 0.05). There, however, were no difference in nutrient reserve concentrations in the hemolymph and ovaries. In the eggs, there was the same trend among treatments as the hepatopancreas nutrient reserves, indicating that both eyestalk ablation and pre-maturation culture conditions (i.e., either biofloc or clear-water) affected the quality of eggs in L. vannamei. [ABSTRACT FROM AUTHOR]