Development of a new protocol for freeze-drying preservation of Pseudoalteromonas nigrifaciens and its protective effect on other marine bacteria

Background: Freeze-drying is known as one of the best methods to preserve bacterial strains. Protectant is the key factor affecting the survival rate of freeze-dried strains. In addition, salinity, bacterial suspension concentration, drying time, and other factors can also affect the survival rate of strains to varying degrees. At present, there are relatively few studies on freeze-drying preservation of marine bacteria. In the present study, we performed the freeze-drying protectant screening and optimized the preservation conditions for Pseudoalteromonas nigrifaciens, which is widely distributed in marine environment. The protective effects of the screened protectants were verified by 18 other marine bacterial strains. Results: The results indicated that the combination of 5.0% (w/v) lactose, 5.0% (w/v) mannitol, 5.0% (w/v) trehalose, 10.0% (w/v) skim milk powder, 0.5% (w/v) ascorbic acid and 0.5% (w/v) gelatin was the best choice for the preservation of P. nigrifaciens. The suggested salinity and concentration of initial cell suspension were 10 g/L NaCl and 1.0 × 109 CFU/mL, respectively. Furthermore, stationary-phase cells were the best choice for the freeze-drying process. The highest survival rate of P. nigrifaciens reached 52.8% when using 5­10% (w/v) skim milk as rehydration medium. Moreover, the other 18 marine strains belonging to Pseudoalteromonas, Vibrio, Photobacterium, Planomicrobium, Edwardsiella, Enterococcus, Bacillus, and Saccharomyces were freezedried under the abovementioned conditions. Their survival rates were 2.3­95.1%. Conclusion: Collectively, our results supported that the protectant mixture and parameters were beneficial for lyophilization of marine bacteria

Does intensive feeding frequency affect growth performance of common snook Centropomus undecimalis (Bloch, 1792)? / A utilização de frequência alimentar elevada pode afetar o desempenho produtivo do robalo flecha Centropomus undecimalis (Bloch, 1792)?

Abstract Salt water recirculation systems using automatic feeders are a new frontier for marine aquaculture. It is possible to decrease the vulnerability of the traditional fish farming in open systems and reduce wasteful feeding and discharge of effluents, as well as increase the economic returns. An experiment with common snook fingerings (4.31 ± 1.42 g and 8.4 ± 1.0 cm) was performed. Three feeding treatments were evaluated: six, twelve and eighteen feeding times per day. Each treatment had three replications. Among the three tested frequencies (fed 6, 12 and 18 times a day), the feeding frequency of 12 times per day (every two hours) showed the best values of the parameters evaluated for production performance. The final weight values, condition factor, specific growth rate and daily weight gain of the treatment 12 feeding times per day were all significantly higher than the lower and higher frequencies. Our results demonstrate that high feeding frequency is not synonymous of higher performance, but is extremely necessary to find out the best range for the target species. Besides, this relationship between feeding frequency and growth performance might change over weight range. Therefore, future studies should address higher weight ranges for comparison to our results.

Resumo Sistemas de recirculação de água salgada utilizando alimentadores automáticos são uma nova fronteira para a aquicultura marinha. Possibilitam diminuir a vulnerabilidade dos cultivos em sistemas abertos e conferir redução de desperdício de ração e lançamento de efluentes, assim como elevar o retorno econômico. Foi realizado um experimento com juvenis de Robalo-flecha (4,31 ± 1,42 g e 8,4 ± 1,0 cm). Três frequências alimentares foram avaliadas: alimentação seis vezes ao dia; doze vezes ao dia, e; dezoito vezes ao dia. Cada tratamento teve três repetições. Dentre as três frequências avaliadas a frequência alimentar de 12 vezes ao dia foi a que apresentou os melhores valores para os parâmetros zootécnicos avaliados. Os valores obtidos de peso final, fator de condição, taxa de crescimento específico e ganho de peso diário foram todos maiores para a frequência de 12 vezes ao dia do que os obtidos para as frequências maior e menor. Nossos resultados demonstram que elevadas frequências alimentares não são sinônimo de melhor desempenho produtivo, mas é extremamente importante conhecer a frequência ideal para a espécie a ser cultivada. Além disto, a relação entre frequência alimentar e crescimento pode mudar de acordo com a faixa de peso dos indivíduos. Desta forma, é extremamente importante que trabalhos futuros avaliem as frequências aqui estudadas para comparar os resultados em indivíduos maiores.

Asociación de floraciones de algas nocivas y Vibrio spp. en áreas de pesca y acuicultura de bivalvos de moluscos en las bahías de Sechura y Pisco, Perú

Entre febrero de 2010 y mayo de 2014 se realizaron 22 evaluaciones en Pisco y 16 en Sechura; ambas áreas importantes en Perú para la extracción de moluscos y maricultura. La incidencia de Vibrio en el agua de mar fue monitoreada durante las floraciones de algas y en épocas normales. Se midieron parámetros ambientales tales como temperatura y nutrientes. En Sechura, Pseudo-nitzschia seriata y Protoperidinium depressum causaron floraciones de algas y fueron dominantes durante todo el período de evaluación. Las temperaturas en esta zona oscilaron entre 21.8 y 25.3 °C. En Pisco, la concentración Akashiwo sanguinea, Messodinium rubrum y Prorocentrum mínimum y el dinoflagelado Cochlodinium polikrykoides fueron los más frecuentes. Las floraciones de algas nocivas ocurrieron cuando las temperaturas estaban entre 17.1 y 23.3 °C, concentraciones de fosfatos que oscilaban entre 1.22 - 6.85 μM y nitratos 0.15 - 7.85 μM. En mayo de 2012, el dinoflagelado Alexandrium peruvianum causó una floración algal, bajo temperaturas de 18.0 a 23.2 °C, valores de fosfato de 0.73 a 11.56 μM y nitratos de 0.76 a 9.81 μM. Los coliformes fueron bajos < 2 - 23 MPN/100 mL, en ambas bahías durante todo el período de estudio. Vibrio alginolyticus fue la especie dominante. Mientras que V. vulnificus y V. parahaemolyticus se detectaron en Pisco, donde las temperaturas del mar comúnmente son mayores y los casos de infecciones graves por ingestión de mariscos se han asociado con el patógeno V. parahaemolyticus.

Between February 2010 and May 2014, 22 surveys in Pisco and 16 in Sechura were conducted; both are major areas for shellfish production and mariculture in Peru. The incidence of Vibrio in seawater was monitored during algal blooms and in their absence. Environmental parameters such as temperature and nutrients were measured. In Sechura, Pseudo-nitzschia seriata and Protoperidinium depressum caused algal blooms and were dominant throughout the evaluation period. The temperatures in this area ranged from 21.8 to 25.3 °C. In Pisco, the harmful algal bloom-forming Akashiwo sanguinea, Messodinium rubrum, and Prorocentrum minimum and the dinoflagellate Cochlodinium polikrykoides were most prevalent. Harmful algal blooms occurred when temperatures were between 17.1 and 23.3 °C, with phosphates ranging 1.22 - 6.85 μM and nitrates 0.15 - 7.85 μM. In May 2012, the dinoflagellate Alexandrium peruvianum caused an algal bloom, with temperatures ranging 18.0 to 23.2 °C, phosphate values from 0.73 to 11.56 μM, and nitrates from 0.76 to 9.81 μM. Coliforms were low, < 2 - 23 MPN/100 ml, in both bays throughout the study period. Vibrio alginolyticus was the dominant Vibrio spp. predominated in both bays, while V. vulnificus and V. parahaemolyticus were detected in Pisco, where warmer sea temperatures are common and severe infections cases by seafood ingestion has been associated with a pathogen V. parahaemolyticus.

Does intensive feeding frequency affect growth performance of common snook Centropomus undecimalis (Bloch, 1792)?

Abstract Salt water recirculation systems using automatic feeders are a new frontier for marine aquaculture. It is possible to decrease the vulnerability of the traditional fish farming in open systems and reduce wasteful feeding and discharge of effluents, as well as increase the economic returns. An experiment with common snook fingerings (4.31 ± 1.42 g and 8.4 ± 1.0 cm) was performed. Three feeding treatments were evaluated: six, twelve and eighteen feeding times per day. Each treatment had three replications. Among the three tested frequencies (fed 6, 12 and 18 times a day), the feeding frequency of 12 times per day (every two hours) showed the best values of the parameters evaluated for production performance. The final weight values, condition factor, specific growth rate and daily weight gain of the treatment 12 feeding times per day were all significantly higher than the lower and higher frequencies. Our results demonstrate that high feeding frequency is not synonymous of higher performance, but is extremely necessary to find out the best range for the target species. Besides, this relationship between feeding frequency and growth performance might change over weight range. Therefore, future studies should address higher weight ranges for comparison to our results.

Resumo Sistemas de recirculação de água salgada utilizando alimentadores automáticos são uma nova fronteira para a aquicultura marinha. Possibilitam diminuir a vulnerabilidade dos cultivos em sistemas abertos e conferir redução de desperdício de ração e lançamento de efluentes, assim como elevar o retorno econômico. Foi realizado um experimento com juvenis de Robalo-flecha (4,31 ± 1,42 g e 8,4 ± 1,0 cm). Três frequências alimentares foram avaliadas: alimentação seis vezes ao dia; doze vezes ao dia, e; dezoito vezes ao dia. Cada tratamento teve três repetições. Dentre as três frequências avaliadas a frequência alimentar de 12 vezes ao dia foi a que apresentou os melhores valores para os parâmetros zootécnicos avaliados. Os valores obtidos de peso final, fator de condição, taxa de crescimento específico e ganho de peso diário foram todos maiores para a frequência de 12 vezes ao dia do que os obtidos para as frequências maior e menor. Nossos resultados demonstram que elevadas frequências alimentares não são sinônimo de melhor desempenho produtivo, mas é extremamente importante conhecer a frequência ideal para a espécie a ser cultivada. Além disto, a relação entre frequência alimentar e crescimento pode mudar de acordo com a faixa de peso dos indivíduos. Desta forma, é extremamente importante que trabalhos futuros avaliem as frequências aqui estudadas para comparar os resultados em indivíduos maiores.

Sperm cryopreservation of lane snapper Lutjanus synagris(Linnaeus, 1758) / Criopreservação do sêmen do ariocó Lutjanus synagris (Linnaeus, 1758)

AbstractThis study aims developing and evaluate a protocol of semen cryopreservation of the lane snapper Lutjanus synagris. Firstly, sperm motility rate, motility time, density and spermatocrit were appraised to characterize the sperm quality of the lane snapper. The effect of three extenders with distinct ionic compositions and pH values combined with seven concentrations of cryoprotector dimethylsulfoxide (0; 2.5; 5.0; 7.5; 10.0; 12.5 e 15.0%), five cooling rates (110, 90, 60, 45 e 30°C –min), nine equilibration time (1; 2,5; 5; 10; 15; 20; 25; 30 e 60 minutes) e five dilutions ratio (1:1; 1:3; 1:6; 1:10 e 1:20) on the sperm motility rate and motility time were analyzed. Fertilization test was accomplished to evaluate the viability of the cryopreserved sperm. The higher sperm motility rate and motility time (P<0.05) was achieved by combining extender with pH 8.2 with 10% concentration of dimethylsulfoxide and cooling rate 60°C –min, 1 minute of equilibration time and 1:3 (v/v) dilution ratio. The use of cryopreserved sperm presented fertilization rates >60% validating the present protocol for lane snapper. The cryoconserved sperm of lane snapper is a viable alternative, being possible to maintain appropriate sperm viability.

ResumoEste estudo teve a finalidade de desenvolver e avaliar um protocolo de crioconservação do sêmen do ariocó Lutjanus synagris. Para caracterizar o sêmen foram avaliados a taxa de motilidade, a duração da motilidade, a concentração espermática e o espermatócrito. Em seis experimentos foram analisados os efeitos de três diluentes, com distintas composições iônicas e valores de pH distintos, combinados com sete concentrações de dimetilsulfóxido (0; 2,5; 5,0; 7,5; 10,0; 12,5 e 15,0%), cinco velocidades de congelamento (–110, –90, –60, –45 e –30°C/min), nove tempos de equilíbrio (1; 2,5; 5; 10; 15; 20; 25; 30 e 60 minutos) e cinco proporções de sêmen:diluente (1:1; 1:3; 1:6; 1:10 e 1:20) sobre a taxa de motilidade e a duração da motilidade espermáticas. Posteriormente um teste de fertilização foi realizado para avaliar a viabilidade do sêmen crioconservado. O tratamento que propiciou maior taxa de motilidade e duração da motilidade espermáticas (P<0,05) foi aquele proporcionado pelo emprego do diluente com pH 8,2 com dimetilsulfóxido a 10%, em uma velocidade de congelamento de –60°C/min, com tempo de equilíbrio de 1 minuto e na proporção de 1:3 (v/v). O sêmen crioconservado apresentou taxa de fertilização superior a 69% validando o presente protocolo para o ariocó. A crioconservação do sêmen do ariocó é uma alternativa viável, sendo possível manter uma apropriada qualidade espermática.

First record of Neobenedenia “melleni” – like species (Monogenea: Capsalidae) in Goliath grouper Epinephelus itajara in Brazil / Primeiro registro de Neobenedenia tipo “melleni” (Monogenea: Capsalidae) em meros (Epinephelus itajara) no Brasil

Neobenedenia melleni (MacCallum, 1927) (Monogenea) is a pathogen widely spread in marine teleost cultures around the world. The present paper recorded this parasite species in the Goliath grouper Epinephelus itajara for the first time Brazil. The use of freshwater bath for parasite control was successful for the Goliath grouper.

Neobenedenia melleni (MacCallum, 1927) (Monogenea) é um patógeno largamente distribuído em culturas de teleósteos marinhos no mundo. No presente trabalho, esta espécie de parasito é registrada pela primeira vez no Mero Epinephelus itajara, no Brasil. A utilização de um banho de água doce foi eficiente para eliminar os parasitos no Mero.

First record of Caligus mutabilis (Copepoda: Caligidae), in sea-farmed Mycteroperca microlepis (Perciformes: Serranidae) in Brazil / Primeiro registro de Caligus mutabilis (Copepoda) em cultivos de Mycteroperca microlepis (Perciformes: Serranidae) no Brasil

Sea lice (copepods) are widespread pathogens in marine teleost cultivation around the world. The sea louse Caligus mutabilis Wilson, 1905, is recorded here for the first time in sea-farmed gag grouper, Mycteroperca microlepis, in Brazil.

Os piolhos marinhos (copépodes) são patógenos amplamente difundidos nos cultivos de teleósteos marinhos ao redor do mundo. O copépode Caligus mutabilis Wilson, 1905 é aqui registrado pela primeira vez em cultivos de badejo-de-areia, Mycteroperca microlepis, no Brasil.

First record of Neobenedenia melleni (Monogenea: Capsalidae) in sea-farmed cobia (Rachycentron canadum) in Brazil / Primeiro registro de Neobenedenia melleni (Monogenea: Capsalidae) em cultivo de bijupirás (Rachycentron canadum) no Brasil

Neobenedenia melleni (MacCallum, 1927) (Monogenea) is a widespread pathogen in marine teleost cultures all over the world. The present paper reports this parasite species in farmed cobia (Rachycentron canadum) in Brazil, for the first time. Some comments on preventive actions for avoiding the disease are made.

Neobenedenia melleni (MacCallum, 1927) (Monogenea) é um patógeno amplamente distribuído em cultivo de teleósteos marinhos no mundo. Este estudo relata pela primeira vez essa espécie de parasito em cultivo de cobia, Rachycentron canadum, no Brasil. Comentários sobre prevenção para evitar a doença são discutidos.

Performance of pilot-scale vertical flow constructed wetlands with and without the emergent macrophyte Spartina alterniflora treating mariculture effluent

Vertical flow constructed wetlands, planted with and without Spartina alterniflora, were tested for the treatment of mariculture wastewater. Wetlands with and without the emergent macrophyte produced reductions of 89 and 71 percent for inorganic solids, 82 and 96 percent for organic solids, 51 and 63 percent for total nitrogen, 82 and 92 percent for ammoniacal nitrogen, 64 and 59 percent for orthophosphate, and 81 and 89 percent for turbidity, respectively. Wetlands with S. alterniflora showed denitrification tendencies, while wetlands without S. alterniflora had higher oxygen levels leading to nitrification. The results suggest the fundamental role of oxygen controlling the purification processes as well as the potential of constructed wetlands to treat mariculture effluents.

Implications of coral harvest and transplantation on reefs in northwestern Dominica

In June, 2002, the government of Dominica requested assistance in evaluating the coral culture and transplantation activities being undertaken by Oceanographic Institute of Dominica (OID), a coral farm culturing both western Atlantic and Indo-Pacific corals for restoration and commercial sales. We assessed the culture facilities of OID, the condition of reefs, potential impacts of coral collection and benefits of coral transplantation. Coral reefs (9 reefs, 3-20m depth) were characterized by 35 species of scleractinian corals and a live coral cover of 8-35%. Early colonizing, brooders such as Porites astreoides (14.8% of all corals), P. porites (14.8%), Meandrina meandrites (14.7%) and Agaricia agaricites (9.1%) were the most abundant corals, but colonies were mostly small (mean=25cm diameter). Montastraea annularis (complex) was the other dominant taxa (20.8% of all corals) and colonies were larger (mean=70cm). Corals (pooled species) were missing an average of 20% of their tissue, with a mean of 1.4% recent mortality. Coral diseases affected 6.4% of all colonies, with the highest prevalence at Cabrits West (11.0%), Douglas Bay (12.2%) and Coconut Outer reef (20.7%). White plague and yellow band disease were causing the greatest loss of tissue, especially among M. annularis (complex), with localized impacts from corallivores, overgrowth by macroalgae, storm damage and sedimentation. While the reefs appeared to be undergoing substantial decline, restoration efforts by OID were unlikely to promote recovery. No Pacific species were identified at OID restoration sites, yet species chosen for transplantation with highest survival included short-lived brooders (Agaricia and Porites) that were abundant in restoration sites, as well as non-reef builders (Palythoa and Erythropodium) that monopolize substrates and overgrow corals. The species of highest value for restoration (massive broadcast spawners) showed low survivorship and unrestored populations of these species were most affected by biotic stressors and human impacts, all of which need to be addressed to enhance survival of outplants. Problems with culture practices at OID, such as high water temperature, adequate light levels and persistent overgrowth by macroalgae could be addressed through simple modifications. Nevertheless, coral disease and other stressors are of major concern to the most important reef builders, as these species are less amenable to restoration, collection could threaten their survival and losses require decades to centuries to replace. Rev. Biol. Trop. 58 (Suppl. 3): 111-127. Epub 2010 October 01.

En junio del año 2002 el gobierno de Dominica solicitó asistencia para evaluar el Instituto Oceanográfico de Dominica (OID), una operación de cultivo de corales del océano Atlántico y del Indo Pacifico para propósitos de restauración y comercio. Evaluamos las facilidades de cultivo del OID, la condición de los arrecifes y el impacto potencial de la recolección de corales y los posibles beneficios del transplante de colonias. Los arrecifes de coral (9 arrecifes de profundidades entre 3 y 20m se caracterizaban por 35 especies escleractíneos y una cobertura viva de coral entre 8 y 35%. Las especies que liberan larvas tales como Porites astreoides (14.8 % de todos los corales), P. porites (14.8%), Meandrina meandrites (14.7%) y Agaricia agaricites (9.1%) fueron los más abundantes, pero sus colonias eran pequeñas (promedio de 25cm de diámetro). El complejo de Montastraea annularis fue otro grupo dominante (20.8% de todos los corales) y sus colonias eran mayores (promedio de 70cm de diámetro). Entre todas las especies los corales habían perdido el 20% de sus tejidos, con un promedio de 1.4% por mortandad reciente. Las enfermedades de coral afectaron 6.4% de todas las colonias, con la incidencia mayor en Cabrits Oeste (11%), Bahía Douglas (12.2%) y el arrecife de Coconut Afuera (20.7%). Plaga blanca y la enfermedad de la banda amarilla causaron la mayoría de la pérdida de tejido vivo, especialmente en el complejo de M. annularis, con impactos localizados por caracoles coralívoros, sobre crecimiento por macroalgas, impactos de tormentas y sedimentación. Mientras los arrecifes parecen estar declinando substancialmente, los esfuerzos de restauración de OID no parecen entablar su recuperación debido a que las especies escogidas para transplantar con las mayores tasas de sobrevivencia incluyen especies que liberan larvas (Agaricia y Porites) que fueron abundantes en las restauraciones, al igual que los organismos potencialmente parasíticos (Palythoa ...

Anatomia e histologia gastrintestinal da garoupa-verdadeira Epinephelus marginatus (Lowe, 1834) (Teleostei, Serranidae) / Dusky grouper Epinephelus marginatus (Lowe, 1834) (Teleostei, Serranidae) gastrintestinal anatomy and histology

A garoupa-verdadeira (Epinephelus marginatus) é uma espécie de serranídeo com grande importância ecológica e boas perspectivas para o cultivo. A investigação da morfologia do trato digestório, associada à atividade alimentar, é fundamental para a compreensão da biologia dessa espécie e premissa básica para pesquisas sobre requerimentos nutricionais, desenvolvimento de rações e práticas adequadas de manejo alimentar. O presente trabalho descreve a anatomia e, por meio da microscopia de luz, as variações histológicas ao longo do tubo digestório de juvenis de Epinephelus marginatus, correlacionando a histologia de cada seguimento com as respectivas funções e o hábito alimentar. Verificou-se que essa espécie possui elevado número de tipos celulares ao longo do tubo digestório que estão intimamente relacionados com a resposta imunológica inata e adaptativa, permitindo o hábito alimentar detritívoro.

The dusky grouper (Epinephelus marginatus) is a serranida species with great ecological importance and good perspectives for rearing. The investigation of the digestive tract morphology associated to the feeding activity is essential for the understanding of the biology of this species and a basic premise for research on feed requirements, feed development and appropriate feeding methods. The present study describes the anatomy and histological variations along the digestive tract of Epinephelus marginatus juveniles associating the histology with function and feeding habit. It was verified that this species possesses a high number of different cellular types along the digestive tube intimately related with the innate and adaptative immunological responses.

Research of Sequential Extraction Procedure for Heavy Metals in Sediments from Mariculture Area / 分析化学

A sequential extraction procedure has been proposed for the evaluation of the speciation of heavy metals including Cd,Cu,Pb and Zn in sediments from mariculture area,and the speciation of heavy metals was separated and defined as acid soluble fraction,reducible fraction,fraction bound organic matter,fraction bound sulfides and residual fraction. Matrix effects of high salinity on the determination of heavy metals in sediments were eliminated by matrix matching and internal standard methods when inductively couple plasma optical emission spectroscopy (ICP-OES) and mass spectroscopy (ICP-MS) were used,respectively. The results showed that the measured values of marine sediment reference materials were consistent with the standard values when the digestion solutions were determined after dilution. The extraction results of the prepositional extraction procedure and European Community Bureau of Reference Program (BCR) procedure were compared and the selectivity of extractants was investigated. The preliminary studies indicated that this sequential extraction procedure was applicable for evaluating the speciation of heavy metals in sediment with organic substances pollution and eutrophication,especially for fraction bound organic matter and fraction bound sulfides.

Experimental evaluation of pathogenicity of Lactococcus garvieae in black rockfish (Sebastes schlegeli)

Black rockfish (Sebastes schlegeli) is an important mariculture species in Korea. The production of this fish is drastically declined due to bacterial diseases, particularly streptococcosis caused by Lactococcus garvieae. The bacterial surface characteristics of SJ7 and TY6 were found to have capsule but not NB13 and YS18. The experiential evaluation of L. garvieae pathogenicity, the capsular isolates showed high cumulative mortality i.e. SJ7 (100%) and TY6 (60%) compared to non-capsular isolates. Based on this result the capsular isolates L. garvieae were highly suspected as the causative agent of streptococcosis in rockfish.