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ABSTRACT: Different technologies have been developed to improve the performance of Litopenaeus vannamei in low salinity, mainly in super-intensive systems like recirculation and BFT (Biofloc Technology System) systems. However, there is... more
ABSTRACT: Different technologies have been developed to improve the performance of Litopenaeus vannamei in low salinity, mainly in super-intensive systems like recirculation and BFT (Biofloc Technology System) systems. However, there is an accumulation of toxic nitrogenous compounds to the shrimps such as nitrate, that at high concentrations and depending on the salinity of the culture water can be lethal. Acute toxicity tests allow to analyze the relationship between the compound and other abiotic or biotic variables. The aim of this research was to determine the acute toxicity and safety level of nitrate (N-NO3 -) for juveniles of L. vannamei at salinities of 5 and 10g.L-1. For salinity of 5g.L-1, a control and 5 treatments were tested, with nitrate concentrations of 100, 500, 1500, 2500 and 3500mg.L-1.For salinity of 10mg.L-1, a 4500mg.L-1nitrate concentration was added. Juveniles were exposed to concentrations during 24, 48, 72, 96 hours in static system. The Mean Lethal Concent...
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The objective of this study was to investigate the effect of protein levels in the diet, water quality, bioflocs composition and shrimp development of Litopenaeus schmitti reared in different salinities using bioflocs technology (BFT).... more
The objective of this study was to investigate the effect of protein levels in the diet, water quality, bioflocs composition and shrimp development of Litopenaeus schmitti reared in different salinities using bioflocs technology (BFT). Juveniles L. schmitii (2.43 ± 0.35 g) were kept in tanks with 400 L (40 shrimps m-²) in three salinities (19, 26 and 33) and fed two commercial diets (30 and 40% crude protein) during a period of 35 days. Among the water quality parameters monitored, concentrations of nitrite were affected by the interaction of factors protein levels in the diet and salinity and by salinity alone (P<0.05). The shrimps development was affected by factors, salinity and protein level of the diet alone (P<0.05). As for dietary protein, the protein efficiency indicated that shrimps used better this nutrient, when they were fed the diet containing 30% protein content (2.23 ± 0.31) compared to 40% (1.87 ± 0.16) (P<0.05). With respect to salinity, the survival of shr...
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In general, the adverse effect of a chemical compound present in water varies with the concentration and time of exposure to the compound, the nature of the chemical species and age of the exposed organisms. Thus, nitrogen does not... more
In general, the adverse effect of a chemical compound present in water varies with the concentration and time of exposure to the compound, the nature of the chemical species and age of the exposed organisms. Thus, nitrogen does not necessarily cause adverse effects on shrimp, but may, instead, promote sub-lethal effects by long-term exposure. Juvenile Farfantepenaeus brasiliensis (initial mean weight = 0.61 g ± 0.07) were exposed to sub-lethal concentrations of ammonia (0.44 and 0.88 mg L-1), nitrite (5.30 and 10.60 mg L-1) and nitrate (45.60 and 91.20 mg L-1) corresponding to the safe levels for the species. After 40 days of exposure of juveniles to ammonia, nitrite and nitrate, all groups differed significantly (p<0,05) from the control group regarding the growth and survival. Based on the results, it was determined that the shrimp F. brasiliensis was susceptible to nitrogen compounds in concentrations equivalent to supposedly safe levels previously proposed for the specie. Thu...
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Abstract The purpose of this study was to evaluate the effect of partial harvest management on Litopenaeus vannamei reared in BFT system. The experiment lasted for 154 days and it was divided in four experimental treatments according to... more
Abstract The purpose of this study was to evaluate the effect of partial harvest management on Litopenaeus vannamei reared in BFT system. The experiment lasted for 154 days and it was divided in four experimental treatments according to the number of partial harvests. Treatment H0 had no partial harvest, H1 had one partial harvest (50% of total biomass), H2 had two partial harvests (33% of total biomass each), and H4 that had four partial harvests (20% of total biomass each). The shrimps were kept at optimal water quality conditions and were feed three times a day with commercial feed. The results of production parameters such as final weight 16.1 g (H0), 18.9 g (H1), 18.5 g (H2) and 20.1 g (H4), survival 43.67% (H0), 82.7% (H1), 86.6% (H2) and 84.7% (H4), and yield 3.48 kg.m−2 (H0), 5.85 Kg.m−2 (H1), 6.22 kg.m−2 (H2) and 6.14 kg.m−2 (H4) demonstrate significant differences among treatments. These results suggest that the partial harvest management in BFT system can leverage productivity.
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Abstract This study evaluated the influence of different quantities of artificial substrate on water quality and the performance of Litopenaeus vannamei in an integrated biofilm-biofloc culture system. Thus, three treatments were... more
Abstract This study evaluated the influence of different quantities of artificial substrate on water quality and the performance of Litopenaeus vannamei in an integrated biofilm-biofloc culture system. Thus, three treatments were performed: the control, the treatment without the addition of artificial substrate; T200, the treatment with a 200 % increase in the lateral area of the tanks using artificial substrates; and T400, the treatment with a 400 % increase in the lateral area of the tanks using artificial substrates. The study was conducted in nine 800 L tanks over 60 days. The animals were stocked at an initial density of 300 shrimp.m−2 (equivalent to 500 shrimp m-3), with an initial weight of 1.27 g (± 0.48). Ammonia concentrations did not differ significantly between treatments (p > 0.05). Increasing the amount of substrate from 200 % to 400 % did not cause significant differences in the nitrite concentrations between these treatments. However, in the control treatment, nitrite remained high (above 20 mg.L-1) for a long period, negatively affecting shrimp performance. Nitrate was lower in T400, indicating a more dynamic process in the nitrogen cycle when the quantity of artificial substrate increased. Weekly growth rates, final weight, survival, and productivity were higher in the treatments integrating biofilm and biofloc substrates and did not show significant differences between T200 and T400. The results demonstrate the importance of artificial substrates in enhancing the water quality in biofloc culture systems over the long term, mostly in terms of maintaining nitrite concentrations below levels toxic to L. vannamei. The performance of the shrimp and the improved water quality at the end of the study reflected the advantages provided by incorporating artificial substrates in shrimp biofloc culture.
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Abstract Litopenaeus vannamei production in oligohaline waters (0.5–5 g L−1) is a potential alternative for the continuous expansion of shrimp farming. However, ionic imbalance may affect physiological processes and productivity. In this... more
Abstract Litopenaeus vannamei production in oligohaline waters (0.5–5 g L−1) is a potential alternative for the continuous expansion of shrimp farming. However, ionic imbalance may affect physiological processes and productivity. In this work, natural seawater inoculation was used as strategy for correction of ionic composition in a biofloc-dominated oligohaline system and its effects on the water quality and nursery performance were evaluated. A 27-day trial was conducted using an experimental biofloc-dominated oligohaline water, salt formulation was based on the mean concentrations of the major ions present in natural oligohaline waters found in Northeastern Brazil. The trial was composed of four treatments of natural seawater inoculation (3, 6, 10 and 13%) and a control, without inoculation (0%); all with four replicates. Post-larvae (PL) of 22 days (0.057 ± 0.002 g) were stocked at 1000 PL m−3 in 20,150 L indoor circular tanks. Shrimp were fed 40% crude protein commercial diets twice a day at rations adjusted weekly. Water temperature, oxygen saturation, pH, total ammonia nitrogen, nitrite, nitrate, phosphate, alkalinity, hardness, salinity, conductivity, total suspended solids and settleable solids were monitored. Concentrations of the major ions were measured at the Days 0, 14 and 27. Shrimp sampling was performed weekly and the final zootechnical performance was evaluated by final weight, survival, specific growth rate (SGR), weekly growth rate (WGR), yield and food conversion ratio. Salinity, conductivity and hardness significantly increased according to the increase of seawater inoculation, whereas the other parameters did not differ; all of them were within the range recommended for shrimp culture at low salinity, except nitrate for 0%. Concentrations of Cl−, Na+, Mg2+ and K+ and Na+:K+ ratio significantly increased according to the increase of seawater inoculation. Final weight, survival, SGR, WGR and yield were significantly lower in the 0%, but no differences were found among the treatments (from 3% to 13%). The results found in this work indicate that a seawater inoculation at 3% was an efficient strategy to mitigate negative effects of the ionic imbalance on growth performance of PL reared in biofloc-dominated oligohaline systems.
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Spermatophore successive manual extrusions are often employed in hatcheries, but it causes melanin deposition, decreasing sperm quality via cell degeneration. Melanization (brown or black spots) is an indicator of the moment to discard... more
Spermatophore successive manual extrusions are often employed in hatcheries, but it causes melanin deposition, decreasing sperm quality via cell degeneration. Melanization (brown or black spots) is an indicator of the moment to discard males. The evaluation of more efficient strategies is required to avoid it, increasing males’ lifespan. The effects of two temperatures (26 and 30 °C) on closed thelycum Farfantepenaeus paulensis spermatophore melanization and sperm quality after successive manual extrusions were evaluated. Wild-caught males were acclimated to laboratory conditions for 1 week and fed commercial broodstock feed and fresh-frozen food items ad libitum four times a day. Later, a 35-day trial was conducted with 24 males (26.05 ± 2.4 g) randomly distributed into eight 200-L tanks (4.3 shrimps m−2). Temperature was gradually increased from 23 to 26 °C or 30 °C. Only males showing a formed spermatophore and in the intermolt period were submitted to four consecutive manual extrusions every 11 days. Melanization was visually examined in extruded spermatophores, which were weighed. Spermatozoa were released in saline solution and observed in a hemacytometer under a light microscope. Morphological abnormalities (main body or spike malformations) were identified. Total and abnormal spermatozoa were counted in five fields of the hemacytometer to calculate sperm count and abnormal sperm rate. No significant differences were found on sperm quality among extrusions, but from the second extrusion onwards, an increase of melanization was evident. On the other hand, temperature did not affect the occurrence of spermatophore melanization related to successive extrusions.
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This study investigated the effects of the inclusion of Mauritia flexuosa fruit pulp in the diet on the growth performance, economic benefit, muscle composition, total contents of carotenoids and flavonoids, chromaticity parameters, total... more
This study investigated the effects of the inclusion of Mauritia flexuosa fruit pulp in the diet on the growth performance, economic benefit, muscle composition, total contents of carotenoids and flavonoids, chromaticity parameters, total antioxidant capacity, and lipid peroxidation in the hepatopancreas and muscle of the juvenile shrimp Litopenaeus vannamei (weighing 1.26 ± 0.023 g). Five diets (37% protein, 10% lipid) consisting of 0 (control), 1.25%, 2.50%, 5.00% and 10.00% (w/w) M. flexuosa fruit pulp were formulated and provided to the shrimps (n = 50 per tank, treatments in triplicate) for 31 days. Results showed that there were no significant differences between the treatments in terms of the growth capacity, chromaticity parameters, muscle composition and total flavonoid content of shrimps (p > .05). However, the carotenoid content in the muscle and hepatopancreas of the shrimps was significantly increased due to the dietary carotenoids present in M. flexuosa fruit pulp (p < .05). This increase in the carotenoid content directly favoured the increase in the antioxidant capacity in the hepatopancreas and muscle of the shrimps (R² = 0.99 and R² = 0.97 respectively; p < .05). There was also a direct relationship between the carotenoid content and the decrease in lipid peroxidation in the hepatopancreas (R² = 0.90; p < .05). The feed cost kg⁻¹ in terms of weight gain and protein production decreased with the inclusion of high levels of M. flexuosa fruit pulp, reaching 8.11% and 18.76% of cost reduction, respectively, with the addition of 5.00% of M. flexuosa fruit pulp. Therefore, the inclusion of M. flexuosa fruit pulp in the diets of shrimp can increase the carotenoid content and the antioxidant capacity in the hepatopancreas and muscle, reduce lipid peroxidation in the hepatopancreas, and probably provide economic benefits for the rearing of juvenile shrimps.
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Abstract The aim of this study was to determine the effects of nitrite on the growth and survival of the white shrimp L. vannamei in two different salinities. Nitrite concentrations tested in salinity 8 g/L were 0 (control), 2.5, 5.0,... more
Abstract The aim of this study was to determine the effects of nitrite on the growth and survival of the white shrimp L. vannamei in two different salinities. Nitrite concentrations tested in salinity 8 g/L were 0 (control), 2.5, 5.0, 10.0, and 20.0 mg NO2−-N/L, and in salinity 24 g/L were 0 (control), 5.0, 10.0, 20.0, and 40.0 mg NO2−-N/L. For these experiments, 30 experimental units with 30 L of useful volume were stocked with 20 juvenile L. vannamei (8.0 ± 0.50 g), corresponding to a stocking density of 100 shrimp/m2, and cultivated for an experimental period of 30 days. A significant difference was found between the control and treatment groups with respect to growth and survival. The 2.5 mg NO2−-N/L treatment showed the best performance indexes in salinity 8 g/L, while the best growth performance indexes were found in the control and 5.0 mg NO2−-N/L treatments in salinity 24 g/L. Total mortality was observed in the 10 and 20 mg NO2−-N/L treatment groups from salinity 8 g/L and in the 40 mg NO2−-N/L treatment group in salinity 24 g/L. This study determined that concentrations of nitrite of up to 2.5 and 10 mg/L are acceptable for the rearing of L. vannamei in salinities of 8 and 24 g/L, respectively.
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Abstract The purpose of this study was to evaluate the effect of water temperature on the antioxidant (gills, hemolymph and hepatopancreas) and immunological systems (hemolymph) of Litopenaues vannamei reared with no water exchange. A... more
Abstract The purpose of this study was to evaluate the effect of water temperature on the antioxidant (gills, hemolymph and hepatopancreas) and immunological systems (hemolymph) of Litopenaues vannamei reared with no water exchange. A 60-day trial was conducted at different temperatures (15, 21, 27—control and 33 °C), with 3 replicate tanks for each treatment. The immunologic parameters analyzed were as follows: hyaline and granular hemocyte count, total protein and apoptosis. The enzymatic and lipid peroxidation assays consisted of glutamate cysteine ligase (GCL), reduced glutathione (GSH) and thiobarbituric acid-reactive substances (TBARS). There were no significant differences (p > 0.05) in immunological parameters among treatments throughout the experimental period. Shrimp exposed to 15 °C at 30 days exhibited significantly higher GCL activity in gills compared to 21 °C (1166.28%), 27 °C (422.96%) and 33 °C (809.37%). L. vannamei reared at 15 °C had the highest GSH concentration at 30 days. The GSH increase in gills was 390.29, 376.94 and 361.75% at 21, 27 and 33 °C, respectively. On day 30, shrimp subjected to 33 °C had higher TBARS levels (6157.14; 8620.00 and 14,336.66% at 15, 21 and 27 °C, respectively). Shrimp reared at 15 °C exhibited higher activity of the rate-limiting compound for GSH production (GCL) and higher concentrations of this non-enzymatic antioxidant. This increased activity may counteract the overproduction of reactive oxygen species generated by temperature stress. We further noted that at 33 °C, the animals showed higher lipid peroxidation. The lowest stress response was observed in shrimp reared at 27 °C (the control group). Therefore, the extreme temperatures should be avoided. Statement/relevance This study present new results about handling and welfare.
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A feeding trial evaluated the replacement of fishmeal by soybean meal in practical diets on the survival and growth of the shrimp Farfantepenaeus paulensis. Six iso-energetic and iso-proteic diets were fed to shrimp for 28 days.... more
A feeding trial evaluated the replacement of fishmeal by soybean meal in practical diets on the survival and growth of the shrimp Farfantepenaeus paulensis. Six iso-energetic and iso-proteic diets were fed to shrimp for 28 days. Replacement levels of fishmeal were 0 (control), 12, 24, 36, 48 and 60%. Post-larvae with mean initial weight of 1.22mg (±0.44) were stocked at random in 40-L tanks. Survival ranged between 70 and 80% and were not different (P>0.05) between treatments. Feeding the diet with 60% of fishmeal replacement resulted in the highest weight gain (P<0.05), while the control diet (no replacement) had the lowest weight gain among all treatments. Similarly, specific growth rate (SGR) was also higher for the 60% diet and lower for the control. Mean final weight ranged from 20.84 to 27.37mg, while SGR varied between 9.1 and 10.7% day-1. The replacement of 60% of fishmeal by soybean meal is recommended in practical diets for F. paulensis as it results in higher weight...
In Brazil's southern and southeastern coast, sport fisheries have a large demand for live bait-shrimp that is usually not met by local fishermen. The production of 4-5 g shrimp in cages may therefore provide a promising alternative to... more
In Brazil's southern and southeastern coast, sport fisheries have a large demand for live bait-shrimp that is usually not met by local fishermen. The production of 4-5 g shrimp in cages may therefore provide a promising alternative to fill this gap. Unfortunately, studies defining adequate management guidelines for the production of live bait-shrimp in cages are as yet not available. In this study, the influence of stocking density on the survival, growth and food conversion ratio (FCR) of the shrimp Farfantepenaeus paulensis reared in cages was evaluated. The trial lasted 42 days and assessed three stocking densities (50, 100 and 200/m 2) of F. paulensis juveniles (mean initial weight of 1.04 g). Final survival and weight of shrimp reared at 50, 100 and 200/m 2 were 94.1, 94.6 and 59.2%, and 6.0, 5.0 and 4.3 g, respectively. Survival and final weight of shrimp were negatively related to density. FCR was not significantly different between treatments but tended to increase at hi...
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The acute toxicity of total ammonia-N, (NH3 + NH4+), and un-ionized ammonia-N, NH3-N, on newly hatched Artemia nauplii and Artemia adults was measured in 24, 48, 72, and 96-h semi-static bioassays system. There was a significant... more
The acute toxicity of total ammonia-N, (NH3 + NH4+), and un-ionized ammonia-N, NH3-N, on newly hatched Artemia nauplii and Artemia adults was measured in 24, 48, 72, and 96-h semi-static bioassays system. There was a significant difference (P < 0.05) in medial lethal concentrations (LC50) obtained during the tests. The LC50 values on nauplii ranged from 650 mg/l, in 24-h, to 399.1 mg/l total ammonia-N, in 96-h, while the LC50 values on adults ranged from 1290.4 mg/l to 600.5 mg/l total ammonia-N, in the same period. Two methods for calculations of un-ionized ammonia toxicity are analyzed and discussed.
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Este estudo foi realizado com o objetivo de avaliar a possibilidade de reduzir a concentração proteica da dieta para pós-larvas de camarão-branco-do-pacífico (Litopenaeus vannamei) por meio da suplementação do aminoácido taurina. Seis... more
Este estudo foi realizado com o objetivo de avaliar a possibilidade de reduzir a concentração proteica da dieta para pós-larvas de camarão-branco-do-pacífico (Litopenaeus vannamei) por meio da suplementação do aminoácido taurina. Seis dietas práticas, isoenergéticas (15,48 kJ EM/g), foram formuladas para conter duas concentrações de proteína (35% e 45% proteína bruta, PB), com três níveis de suplementação de taurina (0, 5 e 10 g/kg), em arranjo fatorial 2 × 3, com quatro repetições. Cem pós-larvas (peso inicial de 0,14 ± 0,01 g) foram estocadas em cada um dos 24 tanques de 45 litros conectados a um sistema de recirculação de água marinha. As dietas experimentais foram distribuídas aos camarões (10% da biomassa) três vezes ao dia, durante 30 dias. A concentração proteica da dieta não influenciou o crescimento nem a utilização alimentar das pós-larvas, mas o efeito benéfico da suplementação das dietas com taurina foi evidente em ambos os níveis proteicos testados. As pós-larvas alimen...
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The shrimp Farfantepenaeus paulensis is considered a suitable species for culture in the Patos Lagoon estuary, southern Brazil, where its catch has been decreasing in the last few years. Considering the potential of estuarine areas for... more
The shrimp Farfantepenaeus paulensis is considered a suitable species for culture in the Patos Lagoon estuary, southern Brazil, where its catch has been decreasing in the last few years. Considering the potential of estuarine areas for shrimp farming, the application of low-cost structures to culture shrimp, such as the pen enclosures, is being proposed as an alternative source of income for artisanal fishermen and farmers living near Patos Lagoon. From an economical standpoint, these alternative systems present several advantages over the traditional pond-based culture systems since land, water pumping and artificial aerations are not required, high natural productivity is available and inexpensive materials are employed in the construction of grow-out structures. This paper reviews the farming of F. paulensis in the pen enclosures as an alternative to the artisanal fishing communities of the Patos Lagoon estuary. Particular emphases are placed on the development of culture systems...
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Title: A laboratory-based effort to investigate the bioaccumulation of elements associated to the total airborne particulate matter in a globally representative crustacean, the White Shrimp (Litopenaeus vannamei). Background: Adverse... more
Title: A laboratory-based effort to investigate the bioaccumulation of elements associated to the total airborne particulate matter in a globally representative crustacean, the White Shrimp (Litopenaeus vannamei). Background: Adverse effects of air pollution are a health concern, especially those related to particulate matter (PM) exposure. However, potential ecotoxicological effects of this complex matrix are not well understood or even evaluated. We hypothesized that the bioaccumulation of elements (especially metals) could be observed in aquatic organisms as a primary ecotoxicological impact of air pollution.
Significant amounts of plant material have been detected in the stomach contents of Farfantepenaeus paulensis juveniles inhabiting the Patos Lagoon estuary, southern Brazil. A 20-day long laboratory feeding experiment was performed to... more
Significant amounts of plant material have been detected in the stomach contents of Farfantepenaeus paulensis juveniles inhabiting the Patos Lagoon estuary, southern Brazil. A 20-day long laboratory feeding experiment was performed to evaluate survival and growth of F. paulensis juveniles (0.84 ± 0.24 g; mean initial body weight ± sd) fed on three distinct plant diets. The feeding treatments consisted of: (1) macroalga Enteromorpha sp. (Entero treatment); (2) seagrass Ruppia maritima (Ruppia treatment); (3) saltmarsh Spartina sp. (Spartina treatment); (4) commercial diet (CD treatment); and (5) without food (Unfed treatment). Overall, growth and survival of juveniles submitted to plant treatments were similar to the Unfed treatment. Significant growth and survival were observed only in the CD treatment. Results indicated that the plant material tested were not capable to support survival and growth of F. paulensis when offered as the sole food source. It could be suggested that the ...
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Effects of shrimp confinement in a situation of high density stocking in a long term nursery on their growth performance in grow out ponds. Were analized two nurseries with a density of 2000 shrimp m-2 were stocked at two different times.... more
Effects of shrimp confinement in a situation of high density stocking in a long term nursery on their growth performance in grow out ponds. Were analized two nurseries with a density of 2000 shrimp m-2 were stocked at two different times. The first nursery (LTN) lasted 144 days, and the SGR of the animals was 3.0% day-1. The second nursery (STN) lasted 18 days and the specific growth rate (SGR) was 19.9% day-1. On the same day, shrimps were transferred to six lined ponds at a density of 20 shrimp m2 where they remained for 101 days. In the first biometry, the SGR in the LTN treatment, increased to 6.7% day-1 and in the STN it decreased to 5.0% day-1. At the end, shrimps of the LTN and STN treatments reached weights of 8.46 and 6.72 g and had productivities of 1287 and 1015 kg ha-1, respectively. Shrimps reared in nurseries for long periods showed growth and survival rates similar to those obtained using conventional management practices in grow out structures.