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This study aimed to evaluate the integrated culture of the Pacific white shrimp (Litopenaeus vannamei) and the West Indian pointed venus (Anomalocardia flexuosa) reared in a biofloc system. The performance of both species and the phytoplankton community were evaluated. Shrimp monoculture and three stocking densities of West Indian pointed venus (2.5, 5.0 and 7.5 Kg m-3) were evaluated in 0.05 m3 tanks. First of all, the addition of A. brasiliana did not affect the water quality parameters of the culture. Regarding the phytoplankton community, 13 taxa were found: 5 cyanobacteria, 4 dinoflagellates, 3 diatoms and 1 green algae. Although diatoms were dominant at the beginning of cultivation, in the middle and at the end a cyanobacterial dominance was observed (proven by ANOSIM and nMDS). The taxa that most contributed to the abundance of cyanobacteria were Aphanocapsa sp. and Pseudanabaena sp. Regarding the performance of the shrimp, all integrated treatments present the higher growth performances (final weight, yield and survival) when compared to shrimp monoculture. Moreover, gradual mortalities of A. brasiliana were observed, probably due to the high concentration of cyanobacteria. Thus, it can be observed that the integration of molluscs in shrimp culture can reduce the concentration of harmful algae and improve the zootechnical performance of the shrimp.

The purpose of this study was to produce Daphnia magna in wastewater from Tilapia farmed in a biofloc system, to evaluate three different carbohydrate:nitrogen ratios. The experiment was conducted for 30 days following a completely randomized experimental design, with the three treatments: C:N 10:1, C:N 15:1 and C:N 20:1, all fed with Chlorella vulgaris. The physical-chemical variables of the water analyzed were: temperature, dissolved oxygen (DO), pH, TAN, NO2 , hardness and alkalinity. The following growth variables of the Daphnia were also evaluated: Maximum average density (MAD), Maximum density day (MDD), Specific growth rate (SGR), Doubling time (DT) and yield (Y). The water quality variables remained in the range of ideal conditions for the species, presenting significant differences (p

Oil spill events in the marine environment can have a deleterious impact on the affected ecosystems, such as coral reefs, with direct consequences for their socioeconomic value. The mutualistic relationship between tropical corals and their dinoflagellate symbionts (Symbiodiniaceae) provide structural and nutritional basis for a high local biodiversity in oligotrophic waters. Here, we investigated effects of crude oil water-accommodated fraction on the competitive fitness of the model zooxanthellae species Symbiodinium glynnii. Results of laboratory essays demonstrate that crude oil carbon is incorporated into the cellular biomass with a concomitant change of δ13C isotopic value. Carcinogenic/mutagenic polycyclic aromatic hydrocarbons were identified in the culture media and were responsible for a linear reduction in population growth of S. glynnii, presumably related to energy relocation for DNA repair. Additionally, the experiments revealed that physiological effects induced by crude oil compounds are genetically inherited by the following generations under non-contaminated growth conditions, and induce a reduction in the competitive fitness to cope with other environmental parameters, such as low salinity. We suggest that the effects of crude oil contamination represent an imparing factor for S. glynnii coping with anthropogenic drivers (e.g. warming and acidification) and interfere with the delicate symbiont-host relationship of tropical corals. This is especially relevant in the coastal areas of northeastern Brazil where an oil spill event deposited crude oil on shallow water sediments with the potential to be resuspended to the water column by physical and/or biological activity, enhancing the risk of future coral bleaching events.

Ceratium furcoides is an invasive species that has caused ecological imbalance in several reservoirs in Brazil. This study investigates the main factors that may favor the occurrence of Ceratium furcoides blooms in a tropical reservoir from the Northeast Brazil, during an extreme drought season. Samples containing phytoplankton were collected monthly from February to September 2017. Quantitative analysis of C. furcoides was performed and the cell volume was estimated using geometric formulas. Mean biovolume of C. furcoides showed significant differences, ranging from 0.78 mm3 L-1 to 11.29 mm3 L-1 reported in March and September, respectively. Environmental parameters presented low oscillation throughout the study, except the conductivity. Significant relationships among the C. furcoides biovolume, water temperature and soluble reactive phosphate were observed. The findings reported here suggest that adverse conditions caused by a drought season did not negatively affect this species. Resumo Ceratium furcoides é uma espécie invasora que tem causado desequilíbrio ecológico em vários reservatórios no Brasil. Este estudo investiga os principais fatores que podem favorecer a ocorrência de florações de C. furcoides em um reservatório tropical do Nordeste do Brasil, durante um período de seca extrema. Amostras contendo fitoplâncton foram coletadas mensalmente de fevereiro a setembro de 2017. Análises quantitativas de C. furcoides foram realizadas e o volume celular estimado por meio de fórmulas geométricas. O biovolume médio de C. furcoides apresentou diferenças significativas, variando de 0,78 mm3 L-1 a 11,29 mm3 L-1 relatado em março e setembro, respectivamente. Os parâmetros ambientais apresentaram baixa oscilação ao longo do estudo, exceto a condutividade. Relações significativas entre o biovolume de C. furcoides, temperatura da água e fosfato reativo solúvel foram observadas. Os resultados relatados aqui sugerem que as condições adversas causadas por uma estação de seca não afetam negativamente esta espécie.

Dinoflagellates are photosynthetic protists commonly distributed in marine and freshwater environments and can be found in symbiotic associations. They are a significant primary producer and play a fundamental role in the functioning of aquatic ecosystems – especially for coral reefs. Dinoflagellates can produce a wide variety of secondary metabolites, and their toxins can affect fish, birds and mammals. In recent years these toxins have been found to have potential cytotoxic, anticancer, antibiotics, antifungals activities. This mini review covers the main genera of dinoflagellates, and challenges and advances in their cultivation in addition to prospects for development of dinoflagellates-based products., This study was financed in part by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil - Finance Code 001 and AOG is thankful to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (PQ 308063/2019-8)., {"references":["Anderson, D.M., Alpermann, T.J., Cembella, A.D., Collos, Y., Masseret, E. & Montresor, M. (2012). The globally distributed genus Alexandrium: multifaceted roles in marine ecosystems and impacts on human health. Harmful Algae 14: 10-35.","Bachvaroff, T.R., Adolf, J.E., Place & A.R. (2009). Strain variation in Karlodinium veneficum (Dinophyceae): toxin profiles, pigments, and growth characteristics. Journal of Phycology 45: 137-153.","Balech, E. (1989). Redescription of Alexandrium minutum Halim (Dinophyceae) type species of the genus Alexandrium. 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Proteins from microalgal biomass have become promising raw materials in several industrial segments. To evaluate growth performance and protein production under different nutritional conditions, Haematococcus pluvialis was grown in different culture media: BBM, RM, BG-11, and KM2. The cultures were inoculated at 105 cells mL-1, and submitted to a temperature of 24°C, in a continous photoperiod and irradiance of 40 µmol photons m-2 s-1. The highest cell density was observed when H. pluvialis was maintained in BG-11 medium (142 ± 30 × 104 cells mL-1), but no statistical difference was observed when comparing the results with those obtained when culturing this microalga in BBM (101 ± 14 × 104 cells mL-1) and RM (105 ± 5 × 104 cells mL-1) media. Also, the lowest cell density was found when cultivating H. pluvialis in KM2 medium (57 ± 9 × 104 cells mL-1), and there was no statistical difference for doubling time, growth rate and specific growth rate results between treatments. In addition, higher protein contents in H. pluvialis were reported for RM, BG-11, and KM2 culture media at 55.1 ± 5.6, 49.3 ± 3.6 and 58.4 ± 2.8%, respectively; and lower protein content was found using the BBM medium (31.1 ± 2.9%). The highest cell density and biomass were achieved at greater nitrogen availability and a higher nitrogen to phosphorus ratio. The results suggest that H. pluvialis is a potential species for protein production, and that BG-11 is the most suitable medium for growing this microalga as it allowed the achievement of highest biomass production and protein content among the media evaluated. Proteins from microalgal biomass have become promising raw materials in several industrial segments. To evaluate growth performance and protein production under different nutritional conditions, Haematococcus pluvialis was grown in different culture media: BBM, RM, BG-11, and KM2. The cultures were inoculated at 105 cells mL-1, and submitted to a temperature of 24°C, in a continous photoperiod and irradiance of 40 µmol photons m-2 s-1. The highest cell density was observed when H. pluvialis was maintained in BG-11 medium (142 ± 30 × 104 cells mL-1), but no statistical difference was observed when comparing the results with those obtained when culturing this microalga in BBM (101 ± 14 × 104 cells mL-1) and RM (105 ± 5 × 104 cells mL-1) media. Also, the lowest cell density was found when cultivating H. pluvialis in KM2 medium (57 ± 9 × 104 cells mL-1), and there was no statistical difference for doubling time, growth rate and specific growth rate results between treatments. In addition, higher protein contents in H. pluvialis were reported for RM, BG-11, and KM2 culture media at 55.1 ± 5.6, 49.3 ± 3.6 and 58.4 ± 2.8%, respectively; and lower protein content was found using the BBM medium (31.1 ± 2.9%). The highest cell density and biomass were achieved at greater nitrogen availability and a higher nitrogen to phosphorus ratio. The results suggest that H. pluvialis is a potential species for protein production, and that BG-11 is the most suitable medium for growing this microalga as it allowed the achievement of highest biomass production and protein content among the media evaluated.

A type of dredge was introduced as fishing gear along the extractive bank of Mangue Seco - PE from which the largest annual catch of Anomalocardia flexuosa in the world is extracted. This study was carried out with the objective of estimating the selectivity of the new fishing gear and quantitatively evaluating the length classes most compromised by the catches, especially considering 20 mm as the reference value. Specimens larger than this size are most likely to be mature. For the selectivity estimation, the methodology using codends (16 or 20 mm) and small meshed cover (2 mm) was used. To estimate the selectivity parameters, a logistic regression and the Bayesian approach were used. The transition between the state in which the specimen is invulnerable to the fishing gear and vulnerable occurs between 10 and 18 mm, using a 16 mm mesh, and using a 20 mm mesh, this transition is between 14 and 20 mm. Dredgers with 16 mm and 20 mm mesh compromise a large proportion of specimens smaller than 20 mm. If the intention is to protect this part of the population, measures such as total restriction of the 16 mm mesh and use of the 20 mm mesh should be necessary only in the months of less catching incidences, or increasing the mesh to 25 mm. RESUMO: Um tipo de draga foi introduzido como arte de pesca no banco extrativista de Mangue Seco - PE de onde se extrai a maior captura anual de Anomalocardia flexuosa do mundo. Este trabalho foi realizado com objetivo de estimar a seletividade do novo petrecho de pesca e avaliar quantitativamente quais são as classes de comprimento mais penalizadas nas capturas, tendo especialmente como referencial o valor de 20 mm. Exemplares maiores que esse tamanho tem elevada probabilidade de estarem maturos. Para estimativa da seletividade foi utilizado o método com uso de saco (16 ou 20 mm) e sobresaco (2 mm). Para estimativa dos parâmetros de seletividade foi utilizada regressão logística e abordagem bayesiana. A transição entre o estado em que o exemplar é invulnerável à arte de pesca e em que o mesmo seria quase com certeza capturado ocorre para malha de 16 mm entre 10 e 18 mm, enquanto para malha de 20 mm essa transição se dá entre 14 e 20 mm. As dragas com malha de 16 e 20 mm penalizam uma proporção grande de exemplares menores que 20 mm. Se a intenção é proteger essa parcela da população, seriam necessárias medidas como a restrição total da malha de 16 mm e uso da malha de 20 mm somente nos meses de menor incidência de recrutamento, ou o aumento da malha para 25 mm.

Recent advances in microalgae biotechnology have proven that these microorganisms contain a number of bioactive molecules, that can be used as food additives that help prevent disease. The green microalga Chlorella vulgaris presents several biomolecules, such as lutein and astaxanthin, with antioxidant capacity, which can play a protective role in tissues. In this study, we produced and analyzed a C. vulgaris functional alcoholic beverage (produced using a traditional Brazilian alcoholic beverage, cachaça, and C. vulgaris biomass). Assays were conducted in vitro by radical scavenging tests, and in vivo, by modeling cortical spreading depression in rat brains. Scavenging radical assays showed that consumption of the C. vulgaris alcoholic beverage had a DPPH inhibition of 77.2%. This functional alcoholic beverage at a concentration of 12.5 g L-1 significantly improved cortical spreading depression velocity in the rat brains (2.89 mm min-1), when compared with cachaça alone (3.68 mm min-1) and control (distilled water; 3.25 mm min-1). Moreover, animals that consumed the functional beverage gained less weight than those that consumed just alcohol and the control groups. These findings suggest that the C. vulgaris functional alcoholic beverage plays a protective physiologic role in protecting brain cells from the effects of drinking ethanol.

The present study aimed to analyze the growth of Chlorella vulgaris in the effluent of a Biofloc Technology (BFT) system used in the Nile tilapia fingerlings farming. The conditions were cultivated by 10 days at 25 ± 2ºC, 90 μmol photons m−2 s−1 irradiance, under constant aeration (without addition of CO2), and with different BFT effluent proportions (0, 50, and 100%). After 24 hours of the inoculation that marked the beginning of the experiment, the development and multiplication of the cells were verified, demonstrating that the BFT effluent used in the Nile tilapia farming was favorable for the cultivation of the microalga Chlorella vulgaris. As expected, the Provasoli culture medium presented the best performance (1,520 ± 75 104 cells mL-1) in relation to the growth of the microalga. However, during the first four days of cultivation, C. vulgaris showed higher growth in treatments containing BFT effluent. C. vulgaris removed 93.6% of the nitrate contained in the BFT effluent. The results of the present study showed the potential use of C. vulgaris on Integrated Multi-Trophic Aquaculture with Nile tilapia fingerlings. In addition to removing nitrate and other nitrogen compounds, C. vulgaris biomass could be used to feed zooplankton or Nile tilapia larvae.

Anomalocardia brasiliana post-larvae were cultured for 28 days to evaluate the effect of stocking density on their growth and survival rate. Three stocking densities were tested 40, 80 and 160 post-larvae cm-2, in experimental units (2-L) with static cultivation system and total water renewal at each 48 hours. The experimental design was completely randomized with three treatments and three repetitions each. Stocking density of 40 post-larvae cm-2 reached 1 mm length within 24 days, while only 18% of the post-larvae at density of 80 post-larvae cm-2 reached 1 mm length in the same time. The density of 40 post-larvae cm-2 had the highest specific growth rate, 4.98±0.08% day-1. The survival rates of post-larvae at lower densities were significantly higher (53.24±4.60% and 52.95±3.32%, on 40 and 80 post-larvae cm-2, respectively) compared to higher stocking density (31.54±0.70%). In the cultivation of A. brasiliana post-larvae, stocking density must be managed during growth. The density of 160 post-larvae cm-2 can only be used until the post-larvae reach 600μm in length, then they should be at 40 post-larvae cm-2 density to keep the maximum daily growth rate. RESUMO: Pós-larvas de Anomalocardia brasiliana foram cultivadas por 28 dias para avaliar o efeito da densidade de estocagem no crescimento e taxa de sobrevivência. Três densidades de estocagem foram testadas: 40, 80 e 160 pós-larvas cm-2, em unidades experimentais (2 L) com sistema de cultivo estatístico e renovação total de água a cada 48 h. O delineamento experimental foi inteiramente casualizado com três tratamentos em triplicata. A densidade de estocagem com 40 pós-larvas cm-2 alcançou 1 mm de comprimento após 24 dias, enquanto apenas 18% das pós-larvas estocadas a 80 pós-larvas cm-2 atingiram 1 mm de comprimento no mesmo período. A densidade de 40 pós-larvas cm-2 apresentou a maior taxa de crescimento específico 4,98±0,08% dia-1. As taxas de sobrevivência de pós-larvas em baixas densidades foram significativamente maiores (53,24 ± 4,60% e 52,95 ± 3,32%, em 40 e 80 pós-larvas cm-2, respectivamente) em comparação com a maior densidade de estocagem (31,54 ± 0,70%). Os resultados sugerem que na criação de pós-larvas de A. brasiliana, a densidade populacional deve ser ajustada durante o crescimento. A densidade de 160 pós-larvas cm-2 só pode ser usada até que as pós-larvas atinjam o comprimento de 600µm; em seguida deve ser alterada para a densidade de 40 pós-larvas cm-2 para manter a taxa máxima de crescimento diário.

The purpose of this study was to produce Daphnia magna in wastewater from Tilapia farmed in a biofloc system, to evaluate three different carbohydrate:nitrogen ratios. The experiment was conducted for 30 days following a completely randomized experimental design, with the three treatments: C:N 10:1, C:N 15:1 and C:N 20:1, all fed with Chlorella vulgaris. The physical-chemical variables of the water analyzed were: temperature, dissolved oxygen (DO), pH, TAN, NO2 , hardness and alkalinity. The following growth variables of the Daphnia were also evaluated: Maximum average density (MAD), Maximum density day (MDD), Specific growth rate (SGR), Doubling time (DT) and yield (Y). The water quality variables remained in the range of ideal conditions for the species, presenting significant differences (p

O presente trabalho teve como objetivo avaliar o desempenho de alevinos de tilapia do Nilo, cultivados em tecnologia de bioflocos, utilizando diferentes densidades de inoculacao de Chlorella vulgaris. O delineamento experimental foi inteiramente casualizado, envolvendo o cultivo em sistema de bioflocos e quatro densidades de Chlorella vulgaris (0; 2,5; 5 e 10x104 cel mL-1), com quatro repeticoes cada. O trabalho teve duracao de 63 dias, sendo realizado em caixas com 40L de volume util, densidade de estocagem de 10 peixes por unidade experimental e peso medio inicial de aproximadamente 1,86 g. As variaveis de qualidade de agua nao apresentaram diferenca significativa entre os tratamentos, principalmente o nitrogenio da amonia total e do nitrito, que estiveram dentro do nivel aceitavel para o cultivo da especie. As variaveis de desempenho zootecnico nao foram afetadas pelas diferentes densidades de inoculacao da microalga, obtendo peso medio final de aproximadamente 21 g para os tratamentos e taxas de sobrevivencia superiores a 80%. Portanto para estas densidades de inoculacao da microalga Chlorella vulgaris, com frequencia semanal, nao apresentaram influencia no crescimento de alevinos de tilapia cultivada com bioflocos.

The temporal phytoplankton biomass variation at two Neotropical reservoirs during an extreme drought season were analyzed. Here we sought to evaluate the main abiotic factors involved in dynamics of phytoplankton during this drought period. The main difference between the reservoirs was the intensive fish and shrimp farming in one of the reservoirs. For quantitative analysis, sampling with bottles were carried out at an average depth of 0.5m. Water temperature, pH and electrical conductivity parameters were measured in situ and water samples were collected for dissolved inorganic nitrogen and soluble reactive phosphorus analyses. Aquaculture was probably one among the causes for the reservoirs were so different in the physical and chemical variables, as shown by the principal components analysis. The results showed specific groups dominance in both reservoirs. In the Cachoeira II reservoir, an invasive dinoflagellate, Ceratium furcoides, was present in all analyzed months, while, in the Saco I reservoir, cyanobacteria group represented more than 50% of phytoplankton biomass, mainly Microcystis aeruginosa and Dolichospermum sp. In two reservoirs precipitation, soluble reactive phosphorus and electrical conductivity were positively related with phytoplankton. Phytoplankton biomass was considerably larger in the Cachoeira II reservoir, due to the greater size and biovolume of the dominant dinoflagellate. These findings suggest that species dominance in extreme drought events may be favored.

A 42-day trial was conducted to evaluate the effects of a low-salinity biofloc system with different stocking densities on water quality and zootechnical performance of Nile tilapia fingerlings (10 g/L). Four treatments were tested at different densities: 500 fish/m³, 750 fish/m³, 1,000 fish/m³ and 1,250 fish/m³, all in triplicate. Fingerlings of Oreochromis niloticus (initial mean weight of 1.17 ± 0.05 g) were stocked in twelve experimental black-plastic tanks (40 L) with no water exchange during the experimental period. Molasses was added daily to the system at 30% of the amount of feed, and fish were given four daily rations of a formulated feed composed of 36% crude protein and 9% lipids. Water quality variables (dissolved oxygen, pH, salinity, TAN, NO 2 , NO 3 and PO 4 3 ) did not demonstrate significant differences between the treatments. However, significant influences (α ≤ 0.05) of the stocking densities were observed for total suspended solids, settleable solids, final weight, yield, and protein efficiency ratio. The results showed survival over 96%, final weight values between 12 and 18 g, yield between 9.49 and 15.27 kg/m 3 , water consumption of 52 to 101 L/kg fish, and total time of settling chambers between 238 and 305 h/kg fish. These results indicate a negative effect of stocking density on final weight, survival, alkalinity, NO 2 , PO 4 3 and water consumption, and a positive effect on yield in Nile tilapia fingerling culture (1-20 g) in a low-salinity biofloc system with densities up to 1000 fish/m³.

The purpose of this study was to determine the moment of the year for the oyster recruitment and define the type of collector and environmental conditions that maximize recruitment. Collections were conducted, during 12 months, on Amazon Macrotidal Mangrove at two different sites: raft (point I) and mangrove (point II). In each location three types of collectors were used (1) transparent PET bottles, (2) green PET bottles, and (3) PVC sheets, each with three replicates. Spats were counted and measured at 45-day intervals, while the environmental data were measured every two weeks. Identification of oyster species occurred by genetic testing (multiplex PCR) by randomly selecting individuals by sampling. Results indicated spat capturing was significantly influenced by the collector type, location and period of collection (P

A 16-week trial was carried out to evaluate an intensive culture system of Litopenaeus vannamei in commercial ponds with zero water exchange. Two management strategies were used: one with the addition of molasses (ML) and the second with commercial probiotic and molasses (PML), each with four replicates. Shrimp L. vannamei (2.09 ± 0.3 g) were stocked in 2.6 ha ponds without liners at a density of 98 shrimp m-2. The commercial probiotics used with molasses was a mixture of Bacillus spp. and Lactobacillus sp. After 16 weeks, no significant differences were found in mean dissolved oxygen, temperature, salinity, pH, total heterotrophic bacteria and zootechnical parameters (yield, FCR, survival and final weight) between the two management strategies. Total ammonia nitrogen concentration (53 to 69%) was the highest inorganic nitrogen compound. There were no significant differences between its concentrations in the two management strategies. The addition of molasses and probiotics are important management strategies for increased shrimp growth in an intensive system in ponds with zero water exchange, however, molasses is cheaper than the probiotics. Molasses inputs were based on a percentage of the daily feed allotments (by weight) and application rates of 30% of total daily feed in combination with commercial probiotics in intensive ponds without liners with zero water exchange was not sufficient to recycle all nitrogen waste with 10 HP ha-1.

Understanding the evolution of scientific literature is a critical and necessary step for the development and strengthening of a research field. However, an overview of global dinoflagellate research remains unavailable. Herein, global dinoflagellate research output was analyzed based on a scientometric approach using the Scopus data archive. The basic characteristics and worldwide interactions of dinoflagellate research output were analyzed to determine the temporal evolution and new emerging trends. The results confirm that dinoflagellate research output, reflected in the number of publications, is a fast-growing area since the mid-1990s. In total, five research subareas emerged using a bibliometric keywords analysis: (1) &ldquo, symbiosis with coral reefs&rdquo, (2) &ldquo, phylogeny&rdquo, (3) &ldquo, palynology&rdquo, (4) &ldquo, harmful algal blooms&rdquo, and (5) &ldquo, nutrition strategies&rdquo, Dinoflagellate publications were modeled by fish production (both aquaculture and fisheries) and economic and social indexes. Finally, directions for future research are proposed and discussed. The presented scientometric analysis confirms that dinoflagellate research is an active and important area with focus on mitigating economic impacts, especially in regard to fish production.

Na presente pesquisa avaliou-se o efeito da relação carbono/nitrogênio (C:N) na qualidade da água, produtividade e composição centesimal dos alevinos de Oreochromis niloticus durante 58 dias de cultivo. O desenho experimental consistiu em quatro tratamentos: um sistema convencional (controle) e três sistemas de biofloco (CN10, CN15 e CN20). Foram utilizadas 12 unidades experimentais de 0,04 m3 com 30 peixes (750 peixes m-3) com peso médio individual de 1,55 ± 0,01 g. Verificou-se a existência de interação entre os parí­¢metros de qualidade da água do sistema de biofloco e os parí­¢metros produtivos dos alevinos de tilápia. O tratamento CN10 apresentou baixa produção de sólidos sedimentáveis, 38,61 ± 0,54 mL L-1 (p

This study examined the filtration and ingestion rates from the Veneridae Anomalocardia brasiliana (Gmelin, 1791) and evaluated the efficiency of reproduction in laboratory. Specimens were collected on Mangue Seco beach, Pernambuco, Brazil. To evaluate the filtration and ingestion rates, experiments were carried out separately: the presence of light (2000 Lux) and absence of light, with three different temperatures (23.5, 27 and 30 oC), and different salinities (20, 25, 30 and 35 g L-1). Spawning was tested by manipulating temperature with the addition of microalgae and gametes in induction treatment and without manipulating water variables by spontaneous spawning treatment. The most active filtration and ingestion for the species occurred in the absence of light, at temperature of 27 oC, and salinity of 30 g L-1. It was found that there is no significant difference between the spontaneous and induction of spawning, however the spontaneous spawning showed a more significant amount of eggs and larvae. These results may contribute to the technology of maintenance breeding under laboratory conditions and seed production of this species for use in culture.

O objetivo deste trabalho foi avaliar a remoção de compostos nitrogenados e fosfatados e da carga orgânica poluidora oriunda de cultivo heterotrófico de camarão marinho, por meio de reator anaeróbico. Foi construído um reator com fluxo ascendente, em que os efluentes de entrada e saída foram avaliados continuamente durante 120 horas, com três repetições. Os parâmetros físicos e químicos avaliados foram: temperatura, pH, condutividade, ortofosfato, nitrito, nitrato, amônia, demanda química de oxigênio e sólidos totais. O reator permaneceu estável, com boas condições de retenção de sólidos. O reator anaeróbico removeu 96,7% do nitrogênio amoniacal e 91% de ortofosfatos dos efluentes de cultivo de camarão marinho, o que mostra que os efluentes tratados estão dentro dos limites estabelecidos pela legislação.

Fluctuations in world harvests of Artemia sp cysts have increased prices sharply in the past years. Several organisms have been tested as alternative sources for a total or partial replacement of Artemia sp, among which the microcrustacean (Anostraca) Dendrocephalus brasiliensis stands out. The objective of this study was to investigate the reproductive strategy of D. brasiliensis by means of AFLP markers. The distinction between sexual and parthenogenetic reproduction was conducted using 7 EcoRI and MseI primer combinations in a full-sib family composed of 13 progenies. Forty polymorphic markers were obtained, of these, 35% were from paternal origin and 65% were maternally inherited. Results showed mendelian segregation in all markers through the chi-square at P≤0.05. Sex changes were observed after 72 hours of grouping individuals of the same sex in a container, suggesting a possible sex density-dependent behavior. Paternal inheritance revealed that this species adopts sexual reproduction under experimental conditions. Há vários anos que a produção de cistos de Artemia sp. apresenta flutuações, o que aumenta consideravelmente o seu valor. Vários organismos têm sido testados para a substituição total ou parcial da Artemia, dentre os quais se destaca o microcrustáceo (Anostraca) Dendrocephalus brasiliensis. O objetivo do presente trabalho foi investigar a estratégia reprodutiva de D. brasiliensis por meio de marcadores de AFLP. A distinção entre uma reprodução sexuada e partenogenética foi feita a partir da genotipagem de sete combinações de primers de AFLP em uma família composta de 13 progênies. Quarenta marcadores polimórficos foram obtidos, dos quais 35% foram de origem paterna e 65%, materna. Os resultados mostraram a segregação mendeliana de todos os marcadores através do teste de qui-quadrado a P≤0.05. Mudanças de sexo foram observadas após 72 horas do agrupamento de indivíduos de mesmo sexo em um recipiente, sugerindo uma possível razão sexual populacional densidade-dependente. A herança paterna mostrou que a reprodução sexual é adotada por essa espécie sob condições experimentais.

Effects of different microalgal diets on the growth and on the survival of Anomalocardia brasiliana larvae between trochophore and pediveliger stages were evaluated. Diets were evaluated in two separate experiments. The first tested the microalgae Isochrisys galbana (Ig), Phaeodactylum tricornutum (Phaeo), Chaetoceros calcitrans (Cca) and the combinations (Ig+Cca), (Ig+Phaeo) and (Cca+Phaeo). The second tested the microalgae C. calcitrans (Cca), Pavlova lutheri (Pl) and the combination (Cca+Pl). When provided alone, I. galbana resulted in survival and growth rates lower than the rest of the diets, and the best results achieved were obtained with P. tricornutum and C. calcitrans supplied alone or combined with other microalgae. However, in the second experiment the diet Cca+Pl resulted in better growth and survival rates (261.67 ± 9.64 μm and 31.50 ± 0.87%) than all diets tested in both experiments, therefore it is recommended for A. brasiliana larvae.

Resumen pt: O marisco Anomalocardia brasiliana apresenta grande importância economica e social na pesca artesanal no litoral norte de Pernambuco. O presente estudo t...

A trial was conducted for 42 days to evaluate the effects of two commercial feeds with high and low crude protein content on the performance of white shrimp Litopenaeus vannamei cultivated in an integrated biofloc system with the seaweed Gracilaria birdiae. The experiment had a 2 × 2 factorial design (a biofloc monoculture or an integrated system with 32% (low) or 40% (high) crude protein content) with the following treatments: IS32 (an integrated system using low protein commercial feed); IS40 (an integrated system using high protein commercial feed); M32 (a monoculture system using low protein commercial feed); and M40 (a monoculture system using high protein commercial feed), all in triplicate. Shrimp individuals (0.23 ± 0.04 g) were stocked at a density of 500 shrimp/m3 and no water exchange was carried out during the experimental period. No significant influence (p > 0.05) was found to be caused by the integrated system or the crude protein levels on water quality. However, a significant influence (p < 0.05) was found for final weight (3.21–4.12 g), weight gain (2.97–3.89 g), yield (1.39–1.96 kg/m3) and feed conversion ratio (1.47–1.74). Growth was similar in IS32, M40 and IS40, indicating that crude protein levels can be reduced with no adverse effect on shrimp performance variables in integrated biofloc systems with G. birdiae.

Resumen en: This study aimed to evaluate the food consumption of marine shrimp Litopenaeus vannamei in a closed culture system with application of probiotics. Four t...

Este estudio fue diseñado para evaluar la supervivencia de poslarvas de camarón sometidas a la prueba de estrés osmótico y su relación con el estado de muda. Se utilizaron poslarvas en los estadios de PL7 a PL17 y sometidas a prueba de estrés osmótico durante la etapa de intermuda (IM), premuda inicial (PrMI) y premuda final (PrMF), determinando su efecto por medio de la supervivencia. Para dicho análisis se tuvo en cuenta el desarrollo branquial de las poslarvas, el peso de los individuos y los parámetros de calidad de agua del cultivo. Se evaluaron 33 tratamientos en triplicado conformados por 2 factores: estadios de muda (IM, PrMI y PrMF) y edad (PL7 hasta PL17). Los resultados indican diferencias significativas para la interacción estadios de muda y edad. La supervivencia más alta se presentó en la etapa de intermuda (74,12%) a partir de PL12.

The aim of this study was to evaluate the effect of the addition of Navicula sp. on plankton composition and postlarvae growth of Litopenaeus vannamei reared in culture tanks with zero water exchange systems. Four treatments were considered: zero water exchange (ZWE); ZWE with the addition of feed (ZWE- F); ZWE with the addition of Navicula sp. (ZWE-N) and ZWE with the addition of feed and Navicula sp. (ZWE- FN), all in triplicate. Shrimp of 17.7 ± 0.02 mg were stocked at a density of 2500 shrimp m -3 and microalgae added on the 1 st , 5 th and 15 th day at a density of 5x10 4 cell mL -1 . The shrimp were fed a commercial feed composed by 42% crude protein four times a day except in the ZWE treatment. For data analysis we used Cochran, Shapiro- Wilk, ANOVA, Tukey and Student-t tests (P < 0.05). The most frequent genera were: Anabaena, Arcella, Asplanchma, Bosmina, Brachionus, Cylindrotheca, Daphnia, Fragilaria, Hemiaulus, Keratella, Orthoseira, Oscillatoria, Phymatodocis, Rhabdonema, Skeletonema, Sckizothrix and Ulothrix. Significant differences between treatments were observed for TAN, NO2-N, alkalinity, final weight, weight gain, final biomass, biomass gain, feed conversion ratio, specific growth rate and survival. The ZWE-FN treatment showed better production parameters, indicating the benefits of the addition of Navicula sp. as a natural food source for L. vannamei postlarvae in zero water exchange systems.

O molusco bivalve Anomalocardia brasiliana (Gmelin. 1791) é conhecido vulgarmente como berbigão, marisco, muçunim ou marisco pedra. A espécie habita, preferencialmente, regiões costeiras protegidas da ação de ondas e correntes, tanto na faixa entremarés como no infralitoral raso, onde se enterra superficialmente no substrato (BOEHS et al., 2004). É uma espécie euritérmica, eurihalina, filtradora e de hábito livre, habitando locais com pouco material em suspensão (NARCHI, 1974). O seu estabelecimento em áreas de suspensão frequente de sedimento está associado ao fato de seus sifões serem curtos e fundidos com tentáculos simples (EL-DEIR, 2009). Neste contexto, o marisco-pedra Anomalocardia brasiliana foi utilizado como organismo- teste devido à sua capacidade de filtração, com o objetivo de avaliar a sua sobrevivência quando exposto a um composto biossurfactante e determinar a concentração letal média (CL50) dessa espécie em bioensaios de 96 h. Os animais empregados nos testes foram coletados em vários pontos da Praia de Mangue Seco (07°50'16"S - 034°50'43"W), Nova Cruz, município de Igarassu, Pernambuco (Figura 1). Após a coleta, foram transportados para o laboratório e mantidos em caixas de fibra de vidro, com volume de 400 litros, em água salgada com salinidade média de 26 e temperatura de 26±0,5oC, sob aeração constante, e alimentados diariamente com uma mistura algal de Chaetoceros gracilis e Navicula sp., em uma concentração de 300 x 104 células/mL, durante um período mínimo de 10 dias, anterior à realização do experimento. O biossurfactante testado apresentou uma letalidade variada para o molusco bivalve Anomalocardia brasiliana, considerando as diluições-teste entre 1:10 e 1:160, com uma sobrevivência maior nas diluições mais elevadas. Os resultados são preliminares, permitindo concluir que o composto possui letalidade para o organismo testado, e sugerir a necessidade da realização de novos experimentos com diluições entre 1:10 e 1:40, para melhor estimativa da CL50 do composto para a espécie.

O objetivo do trabalho foi avaliar o crescimento da microalga Navicula sp. utilizando resí­­duo sólido de um cultivo em sistema de bioflocos como meio de cultura em comparação ao meio Conway. Foram realizados dois experimentos, com e sem adição de metais traços, sendo que cada experimento teve cinco tratamentos com três repetições cada um: R0C100 (100% Conway); R25C75 (25% resí­­duo e 75% Conway); R50C50 (50% resí­­duo e 50% Conway), R75C25 (75% resí­­duo e 25% Conway) e R100C0 (100% resí­­duo). Os cultivos de alga foram realizados em erlenmeyers de 1 L durante 10 dias, com fotoperí­­odo integral e inóculo inicial de 5x104 cél.mL-1. Realizaram-se contagens diárias para acompanhamento da densidade celular máxima, tempo de duplicação e velocidade de crescimento. O pH e a temperatura foram mensurados no iní­­cio e no final dos experimentos. Para as análises estatí­­sticas, utilizaram-se os testes de Cochran, Shapiro Wilk, ANOVA e Tukey (P < 0,05). O pH e a temperatura mantiveram-se dentro dos padrões de cultivo nos dois experimentos. O meio de cultura com resí­­duo de cultivo de camarão em biofloco apresentou resultado semelhante ao do meio Conway e mostrou-se satisfatório para o desenvolvimento da microalga Navicula sp., ressaltando que a presença de metais traços favoreceu o crescimento da espécie.