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1.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 893-901, Jul.-Aug. 2021. tab, graf, mapas, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1285264

ABSTRACT

Survival and growth of the native oyster Crassostrea gasar along the juvenile and adult phases were evaluated in three different stocking densities [low (D), medium (2D) and high (3D)] and in two grow-out systems (fixed and floating system). The fixed system consisted of a rack made with PVC, fixed from the bottom with wood sticks. The floating system consisted of floating bags suspended by a rack made with PVC and maintained submerged from the seawater surface by eight floats. Survival and shell height of oysters cultured after 30, 60 and 90 days were registered in each phase and in each grow-out system. Results showed that the grow-out system did not affect survival and growth of C. gasar in the juvenile and adult phases. The tested densities affected the survival of oysters cultured over time in both phases but did not affect oyster growth. At times analyzed, it was observed positive growth in juvenile oysters grow after 90 days of culture. However, in the adult phase, no growth was observed after 90 days of culture. Oyster yield was higher in the density 3D, in both juvenile and adult phases. These findings contributed to the development of the oyster C. gasar culture.(AU)


A sobrevivência e o crescimento da ostra nativa Crassostrea gasar nas fases juvenil e adulta foram avaliados sob três diferentes densidades de estocagem [baixa (D), média (2D) e alta (3D)] e dois sistemas de engorda (fixo e flutuante). O sistema fixo consistiu em uma mesa de PVC, fixada na parte inferior com varas de madeira. O sistema flutuante consistiu em travesseiros flutuantes suspensos por uma mesa de PVC e mantidas submersas da superfície da água do mar por oito flutuadores. Registraram-se sobrevivência e altura da concha de ostras cultivadas após 30, 60 e 90 dias, em cada fase (juvenil e adulta) e em cada sistema (fixo e flutuante). Os resultados mostraram que o sistema de engorda não afetou a sobrevivência e o crescimento de C. gasar nas fases juvenil e adulta. As densidades testadas afetaram a sobrevivência das ostras ao longo do tempo, em ambas as fases, mas não afetaram o crescimento em altura. Nos tempos analisados, ostras juvenis apresentaram crescimento após 90 dias de cultivo. Porém, na fase adulta, não foi observado crescimento após 90 dias de cultivo. A produção de ostras, foi maior na densidade 3D, nas fases juvenil e adulta. Os presentes achados contribuíram para o desenvolvimento do cultivo da ostra C. gasar.(AU)


Subject(s)
Animals , Aquaculture/methods , Crassostrea/growth & development , Survival , Tropical Climate
2.
Braz. arch. biol. technol ; 64: e21190650, 2021. tab, graf
Article in English | LILACS | ID: biblio-1249213

ABSTRACT

Abstract In the last decades the oyster faming stands out as the main mitigating measure to the decline of the fishery, as it presents socio-economic and environmental viability. However, for the success of the activity, it is necessary to understand the stages of cultivation, as well as the growth performance of the species to be cultivated. The present work aims to characterize the growth and survival of Crassostrea tulipa, cultivated on the Amazon coast. For this purpose, oysters were grouped by commercial size class (seed, juvenile, baby, average and masters) and compared the growth rates and their relationships with the abiotic variables. There was no difference in the average growth between the oyster classes, however, when comparing them in the total and percentage growth rates, a higher performance was observed in the oysters classified by juvenile and seed, respectively. The relationship of salinity to oyster growth was evidenced only in the class of juvenile oysters. The cultivation time required to obtain native oysters in the commercial size varied between four and seven months, being inferior to those found in other Brazilian regions.


Subject(s)
Ostreidae , Aquaculture/methods , Amazonian Ecosystem , Crassostrea
3.
Braz. arch. biol. technol ; 64: e21180617, 2021. graf
Article in English | LILACS | ID: biblio-1285551

ABSTRACT

HIGHLIGHTS Crassostrea oysters larvae patterns in estuarine environments. Larvae distribution patterns in Guaratuba Bay (Paraná State - Brazil).


Abstract Crassostrea oysters present planktonic/planktotrophic larval development. Thus, it is essential knowing larvae distribution patterns in estuarine environments presenting oyster farms and spat collection. The aim of the current research is to investigate the spatio-temporal distribution of oyster larvae in Guaratuba Bay (Paraná State - Brazil) based on monthly samplings conducted with a plankton net (50 cm diameter and 225 µm mesh size) from June 2003 to June 2004 in three different points (Point I - bay´s entrance; Point II - cultivation park; Point III - median sector of the bay). Plankton samples were preserved in 4% buffered formaldehyde. They were concentrated and quantified in the laboratory. The total number of larvae in the sample from each net was counted and corrected to a standard larvae/m3 collection tow. Data about sea water temperature, salinity, transparency and pluviosity were also collected. Based on results about the spatial distribution of larvae, mean density was 33.30 ±42.73 larvae/m³ in Point I; 17.84 ±16.88 larvae/m³ in Point II and 55.53 ±78.31 larvae/m³ in Point III, during the studied period. Spring and Summer were the seasons recording the most expressive mean number of larvae; the largest concentration of them was found in Point III, in the middle section of the bay.


Subject(s)
Ostreidae , Plankton , Crassostrea , Brazil
4.
Rev. bras. parasitol. vet ; 30(1): e023320, 2021. tab, graf
Article in English | LILACS | ID: biblio-1156231

ABSTRACT

Abstract The aim of this study was to detect Toxoplasma gondii DNA in oysters (Crassostrea spp.) sold on seven beaches in the State of Pará, Brazil. According to the National Program for Hygiene and Sanitary Control of Bivalve Mollusks, 100 g of the edible part of mollusks is required to analyze contaminating microorganisms. In this study, 12 oysters were assumed to be equivalent to 100 g of edible parts when preparing each pooled sample. In total, 360 oysters were purchased from 30 vendors. From groups of 12 oysters purchased per vendor, 60 pooled samples were obtained, comprising 30 gill tissues and 30 gastrointestinal tracts. For molecular analysis, nested-PCR was conducted to amplify a 155-base-pair product of the B1 gene from T. gondii. All analyzed samples were negative for T. gondii. Our findings indicate that the oyster samples sold on the beaches in the State of Pará were not contaminated by T. gondii.


Resumo O objetivo deste estudo foi detectar DNA de Toxoplasma gondii em ostras (Crassostrea spp.) comercializadas em sete praias do Estado do Pará, Brasil. De acordo com o Programa Nacional de Controle Higiênico Sanitário de Moluscos Bivalves, 100 g da parte comestível dos moluscos são necessários para a análise de microrganismos contaminantes. Neste estudo, 12 ostras foram consideradas equivalentes a 100 g de partes comestíveis na preparação de cada amostra agrupada. No total, 360 ostras foram compradas de 30 vendedores. De grupos de 12 ostras adquiridas por vendedor, foram obtidas 60 amostras agrupadas, compreendendo 30 tecidos branquiais e 30 tratos gastrointestinais. Para a análise molecular, a nested PCR foi realizada para amplificar um produto de 155 pares de bases do gene B1 de T. gondii. Todas as amostras analisadas foram negativas para T. gondii. Os resultados indicam que as amostras de ostras comercializadas em praias do Estado do Pará não foram contaminadas por T. gondii.


Subject(s)
Animals , Toxoplasma/genetics , Crassostrea , Brazil , Polymerase Chain Reaction/veterinary
5.
Malaysian Journal of Microbiology ; : 390-402, 2021.
Article in English | WPRIM | ID: wpr-972808

ABSTRACT

Aims@#Escherichia coli O157:H7 is known to be transmitted via fecal-oral route, where water plays a role in the transmission process. Oysters as bivalves, bio accumulate pathogens from the water through filter feeding and are suspected to play a role as disease transmission vector. In Malaysia, the data on oyster’s microbiological quality are limited. Hence, it was vital to conduct oyster related studies in Malaysia. The main objectives of this study include the enumeration of most probable number (MPN) of fecal coliforms and E. coli and isolation of E. coli from oyster (Crassostrea iredalei) and water sample for the detection of 16S rRNA and HlyA (Hemolysin A) genes of E. coli O157:H7. @*Methodology and results@#A total of 120 oysters and water samples (n=6) were collected from a fisherman village located in southern Malaysia. Total fecal coliforms and E. coli were determined using the MPN procedure. Colonies of E. coli were identified based on Gram staining, biochemical test, and PCR detection for the presence of 16S rRNA and HlyA gene of E. coli O157:H7. The enumeration results showed that the MPN of the fecal coliforms and E. coli found in the collected oyster samples do not meet the standard to be directed for human consumption (0.72 ± 0.19 × 104 MPN/100 g and 0.13 ± 0.03 × 10 4 MPN/100 g, respectively). The PCR assays showed that 16 out of the 104 (15.38%) of E. coli isolated from water and oysters showed the presence of HlyA gene. The phylogenetic tree analysis showed there were genetic relationships between the HlyA gene of the E. coli isolated in this study with the ones isolated from calf and human faeces.@*Conclusion, significance and impact of study@#The detection of Shiga toxin producing E. coli O157:H7 (HlyA gene) in cage cultured oysters (C. iredalei) and water from southern Malaysia was first time reported here. In the future, more study can be conducted to study the expression of the HlyA gene and confirm of its identity as E. coli O157:H7 using different target genes such as eaeA (encodes a 94 kD outer membrane protein called intimin) and Stx1 (Shiga toxin, Shigella dysenteriae type 1).


Subject(s)
Escherichia coli O157 , Crassostrea
6.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 836-843, 2021.
Article in English | WPRIM | ID: wpr-922766

ABSTRACT

Crassostrea sikamea (C.sikamea) is an important edible and medicinal seafood in China. In the present study, a compound named flazin was separated and identified from the ethyl acetate extract of C.sikamea (EAECs) for the first time. In addition, the 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra zolium (MTS) assay revealed that EAECs and flazin inhibited the transformation of splenic lymphocytes in vitro. Moreover, flazin (20 μg·mL


Subject(s)
Animals , Rats , Carbolines , Crassostrea , Furans , Lymphocytes , Rats, Sprague-Dawley , Spleen
8.
Rev. bras. parasitol. vet ; 29(3): e003720, 2020. graf
Article in English | LILACS | ID: biblio-1138108

ABSTRACT

Abstract The aim of this study was to report on detection of Toxoplasma gondii DNA in oysters (Crassostrea sp.) in the state of Maranhão. To conduct this study, 200 farmed oysters were acquired in the municipality of Raposa and 100 in Paço do Lumiar; and a further 100 oysters were taken from the natural stock in the municipality of Primeira Cruz. This total of 400 specimens sampled was divided into 80 pools composed of five animals each. The gills and visceral mass of each oyster were removed for DNA extraction (per pool of oysters), using a commercial kit. The nested PCR technique (with the primer SAG-1) was then used to investigate any presence of protozoa. This molecular technique demonstrated the presence of DNA of T. gondii in 2.5% of the pools of oysters (n = 2/80): these oysters were exclusively from farms. The results from this study allow the conclusion that oysters of the genus Crassostrea that are farmed in the state of Maranhão are capable of filtering oocysts of T. gondii and maintaining them in their tissues. They are therefore potential sources of contamination for humans and other animals.


Resumo: Objetivou-se com este estudo relatar a detecção do DNA de Toxoplasma gondii em ostras (Crassostrea sp.) no estado do Maranhão. Para a realização do estudo foram adquiridas 200 ostras de cultivo do município de Raposa, e 100 de Paço do Lumiar, além de 100 ostras extraídas de estoque natural do município de Primeira Cruz. Do total de 400 exemplares amostrados, formaram-se 80 pools em que cada pool foi constituído por cinco animais. De cada ostra foi procedida à retirada das brânquias e massa visceral, seguido da extração de DNA de cada pool de ostras, com a utilização de kit comercial. Posteriormente, realizou-se a pesquisa do protozoário por meio da técnica de nested PCR (primer SAG-1). Com a técnica molecular utilizada, foi diagnosticado o DNA do protozoário pesquisado em 2,5% (n=2/80) pools de ostras oriundas exclusivamente de cultivo. Com os resultados obtidos neste estudo, conclui-se que ostras do gênero Crassostrea sp., cultivadas no estado do Maranhão, são capazes de filtrar e manter nos seus tecidos oocistos de T. gondii, sendo, portanto, fontes potenciais de contaminação para seres humanos e outros animais.


Subject(s)
Animals , Toxoplasma/physiology , Crassostrea/parasitology , Brazil , Polymerase Chain Reaction , DNA, Protozoan/genetics , Aquaculture , Oocysts/isolation & purification
9.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1993-1998, Nov.-Dec. 2019. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1055109

ABSTRACT

The effect of three Streptomyces strains (N7, RL8 and V4) and a mixture of Bacillus (BMix) on the growth (Weight, Size) and superoxide dismutase activity (SOD) in hatchery-reared juvenile oysters Crassostrea corteziensis and Crassostrea sikamea was investigated to determine their probiotic potential. Microorganisms were added to culture water at 1×106 CFU/ml once a day during 30 days and all oysters fed daily a microalgae mix. Juveniles of C. sikamea treated with strains N7, RL8 and V4 had a significant weight gain compared to the control group. C. corteziensis juveniles treated with strains RL8 and BMix showed a significantly higher weight gain than the control group. No significant size increase was observed in any treated group for both oyster species. SOD activity significantly increased in C. sikamea treated with RL8 and with RL8, N7 and BMix in C. corteziensis. Streptomyces strains RL8 and N7 emerge as promising probiotic agents to cultivate C. sikamea and C. corteziensis and may also be useful to other molluscs and marine invertebrates .(AU)


O efeito de três culturas Streptomyces (N7, RL8 e V4) e uma mistura de Bacillus (BMix) sobre o cresimento (Peso, Tamanho) e atividade superóxido dismutase (SOD) em ostras jovens Crassostrea corteziensis e Crassostrea sikamea cultivadas artificalmente foi investigado para determinar seu potencial probiótico. Microorganismos foram adicionados à água de cultura a 1×10 6 CFU/ml uma vez por dia durante 30 dias e todas as ostras foram alimentadas diariamente com uma mistura de microalgas. Jovens C. sikamea tratados com culturas N7, RL8 e V4 tiveram ganho de peso significativo quando comparado ao grupo de controle. Jovens C. corteziensis tratados com culturas RL8 e BMix demonstraram peso significativamente mais algo que o grupo de controle. Nenhum aumento em tamanho foi observado em grupos tratados em ambas espécies. A atividade SOD foi significamente aumentada em C. sikamea treatado com RL8 e com RL8, N7 e BMix em C. corteziensis. Culturas Streptomyces RL8 e N7 surgem como agentes probióticos promissores para o cultivo de C. sikamea e C. corteziensis e podem ser úteis para outros moluscos animais marinhos invertebrados.(AU)


Subject(s)
Animals , Streptomyces , Superoxide Dismutase/analysis , Probiotics/administration & dosage , Crassostrea/growth & development
10.
Biosci. j. (Online) ; 35(2): 586-597, mar./apr. 2019. tab, graf, ilus
Article in English | LILACS | ID: biblio-1048612

ABSTRACT

Water salinity is among the most important factors influencing the distribution, abundance, growth, and survival of Crassostrea gasar, an important aquaculture resource grown in estuarine environments in diverse regions of the world. The goal of the present work was to evaluate the effects of different salinities on survival and the tissues ofC. gasar under laboratory conditions. Two experiments were performed using adult oysters from five marine farms located in the bay of Guaratuba, Brazil. In Experiment 1, the daily survival rates were evaluated after the oysters were submitted to gradual acclimatization at salinities ranging from 0 to 65 gL-1 and maintained in the laboratory without feeding for up to 365 days. In Experiment 2, the oysters were exposed to salinity from 0 to 50 gL-1 for up to 30 days without feeding and possible histological alterations caused by salinity were assessed. Three tolerance ranges of C. gasar to salinity were identified: "Optimal" (between 4 and 40 gL-1), "Tolerable" (between 2.1 and 3.9 and between 41 and 50 gL-1) and "Intolerable" (less than 2 and greater than 50 gL-1). No evidence of histological alterations was observed in oysters exposed to the different salinities.


A salinidade da água está entre os fatores de maior influência na distribuição, abundância, crescimento e sobrevivência de Crassostrea gasar, um importante recurso aquícola cultivado em ambientes estuarinos em diversas regiões do mundo. O objetivo desse trabalho foi avaliar os efeitos da salinidade sobre a sobrevivência e nos tecidos de C. gasar exposta a diferentes salinidades, em condições laboratoriais. Foram realizados dois experimentos com ostras adultas provenientes de cinco fazendas marinhas localizadas na baía de Guaratuba, Brasil. No experimento 1, que foi realizado com o propósito de avaliar as taxas diárias de sobrevivência, as ostras foram submetidas à aclimatação gradual a salinidades variando de 0 a 65 gL-1 e mantidas em laboratório, sem alimentação, por até 365 dias. No experimento 2, as ostras foram expostas a salinidades de 0 a 50 gL-1 por até 30 dias, sem alimentação, para avaliação de possíveis alterações histológicas provocadas pela salinidade. Foram identificadas três faixas de tolerância de C. gasar à salinidade: Ótima (entre 4 e 40 gL-1), Tolerável (entre 2,1 e 3,9 e entre 41 e 50 gL-1) e Intolerável (menor que 2 e maior que 50 gL-1). Não foram encontradas evidências de alterações histológicas em função da exposição das ostras às diferentes salinidades.


Subject(s)
Ostreidae , Estuaries , Crassostrea , Salinity , Histology
11.
Rev. bras. parasitol. vet ; 28(1): 97-104, Jan.-Mar. 2019. graf
Article in English | LILACS | ID: biblio-990811

ABSTRACT

Abstract This work describes the detailed ultrastructural morphology of the phagocyte imprisoning an oyster of Nematopsis (Apicomplexa) found in Crassostrea rhizophorae, in the city of Maceió (AL), Brazil. The highly infected hosts had half-open leaflets with weak, slow retraction of the adductor muscles. Variable number of ellipsoid oocytes, either isolated and or clustered, was found between myofibrils of the adductor muscle. Each oocyst was incarcerated in a parasitophorous vacuole of host uninucleated phagocyte. The oocysts were composed of a dense wall containing a uninucleate vermiform sporozoite. The wall of the fine oocysts was composed of homogeneous electron-lucent material formed by three layers of equal thickness, having a circular orifice-micropyle obstructed by the operculum. The oocysts presented ellipsoid morphology with their wall was surrounded by a complex network of numerous microfibrils. Important details of the taxonomic value were visualized such as the ultrastructural organization of the oocyst wall and the organization of the micropyle and operculum, beyond the microfibrils that protrude from the oocyst wall only observed by transmission electron microscopy (TEM) and that may aid in the identification of the species. However, in order to clarify the systematic position of the species reported of the genus Nematopsis, it is important to proceed with genetic analyses.


Resumo Este trabalho descreve a morfologia ultraestrutural detalhada do fagócito encarcerando um oocisto de Nematopsis (Apicomplexa) encontrado em Crassostrea rhizophorae, na cidade de Maceió (AL), Brasil. Os hospedeiros muito infectados apresentavam valvas entreabertas com retração fraca e lenta dos músculos abdutores. Número variável de oócitos de forma elipsoide, isolados e ou agrupados foi encontrado entre as miofibrilas do músculo abdutor. Cada oocisto estava encarcerado num vacúolo parasitóforo do fagócito uninucleado do hospedeiro. Os oocistos eram compostos por uma parede densa contendo um esporozoíto vermiforme uninucleado. A parede dos oocistos finos era composta de material electron-lucente homogêneo formado por três camadas de espessura igual, possuindo um orifício circular - micrópila, obstruída pelo opérculo. Os oocistos apresentavam morfologia elipsoide, sua parede era circundada por uma complexa rede de numerosas microfibrilas. Detalhes de valor taxonômico importantes foram visualizados tais como: a organização ultraestrutural da parede do oocisto e a organização da micrópila e do opérculo, além das microfibrilas que se projetam da parede do oocisto, estrutura apenas observada em microscopia eletrônica de transmissão (MET) e que pode auxiliar na identificação da espécie. Contudo, para esclarecer a posição sistemática da maioria das espécies relatadas do gênero Nematopsis é importante prosseguir com as análises genéticas.


Subject(s)
Animals , Phagocytes/ultrastructure , Apicomplexa/ultrastructure , Oocysts/ultrastructure , Crassostrea/parasitology , Brazil , Apicomplexa/isolation & purification , Microscopy, Electron, Transmission
12.
Chinese Journal of Biotechnology ; (12): 91-101, 2019.
Article in Chinese | WPRIM | ID: wpr-771397

ABSTRACT

Defensins are endogenous cationic antimicrobial peptides rich in arginine and cysteine residues. They are important immune factors resisting pathogenic bacteria infection for mollusks. The 43 amino acid residues near the carboxyl terminal for Crassostrea gigas defensin (CgD) form its mature peptide region, responsible for the biological activity of CgD. First, two target genes, CgDH⁺ (with 6×His-tag at 3' end) and CgDH- (without 6×His-tag at 3' end) were separated and amplified by RT-PCR with specific primers from Crassostrea gigas mantle. These two target genes were ligated to the expression vector pPICZαA to construct recombinant expression vectors, pPICZαA-CgDH⁺ and pPICZαA-CgDH-, which were transformed into competent Pichia pastoris X-33 cells by electroporation respectively. The recombinant target proteins, CgDH⁺ and CgDH-, were induced for 72 h with 1% methanol at 29 °C and 250 r/min. The recombinant CgDH⁺ (5.78 kDa) was purified by immobilized metal affinity chromatography (IMAC), and identified by MALDI-TOF-TOF analysis, demonstrating that it was the expected target protein. Based on the concentration of the purified product, the estimated yield of recombinant CgDH⁺ was 2.32 mg/L. Antimicrobial assay showed that the culture medium supernatant containing recombinant CgDH⁺ and recombinant CgDH-, respectively, had activities against Staphylococcus aureus and Pseudomonas aeruginosa, indicating that the existence of 6×His tag in the recombinant proteins do not affect their biological activities.


Subject(s)
Animals , Anti-Bacterial Agents , Antimicrobial Cationic Peptides , Crassostrea , Defensins , Pichia , Recombinant Proteins
13.
Braz. j. biol ; 78(2): 289-295, May-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-888866

ABSTRACT

Abstract This study reports the pathogen Perkinsus beihaiensis in oysters of the genus Crassostrea on the coast of the State of Bahia (Brazil), its prevalence, infection intensity and correlation with salinity. Oysters (n = 240) were collected between October and December 2014 at eight sampling stations between latitudes 13°55'S and 15°42'S. The laboratory procedures included macroscopic analysis, histology, culture in Ray's fluid thioglycollate medium (RFTM), Polymerase Chain Reaction (PCR) and DNA sequencing. PCR and sequencing have been used for the genetic identification of oysters as well. Two species of oysters have been identified: Crassostrea rhizophorae and C. brasiliana. In both oyster species P. beihaiensis was the only Perkinsus species detected. In C. rhizophorae, the average prevalence was 82.8% by histology and 65.2% by RFTM. In C. brasiliana, the prevalences were 70.5% and 35.7%, respectively. The higher prevalence of P. beihaiensis in C. rhizophorae was probably influenced by salinity, with which was positively correlated (r> 0.8). In both oysters, P. beihaiensis was located mainly in the gastric epithelium. The infection was generally mild or moderate, without apparent harm to the hosts, but in cases of severe infection, there was hemocytical reaction and tissue disorganization. The generally high prevalence in the region suggests that oysters should be monitored with respect to this pathogen, especially in growing areas.


Resumo Este estudo relata o patógeno Perkinsus beihaiensis em ostras do gênero Crassostrea no litoral do Estado da Bahia (Brasil), sua prevalência, intensidade de infecção e correlação com a salinidade. As ostras (n = 240) foram coletadas entre outubro e dezembro de 2014 em oito estações amostrais entre as latitudes 13°55'S e 15°42'S. Os procedimentos laboratoriais incluíram análise macroscópica, histologia, cultivo em meio de tioglicolato de Ray (RFTM), reação em cadeia da polimerase (PCR) e sequenciamento de DNA. PCR e sequenciamento foram também utilizados para a identificação genética das ostras. Foram identificadas duas espécies de ostras: Crassostrea rhizophorae e C. brasiliana. Em ambas as espécies, P. beihaiensis foi a única espécie de Perkinsus detectada. Em C. rhizophorae, a prevalência média foi de 82,8% por histologia e de 65,2% por RFTM. Em C. brasiliana, as prevalências foram de 70,5% e 35,7%, respectivamente. A maior prevalência de P. beihaiensis em C. rhizophorae foi provavelmente influenciada pela salinidade, com a qual este apresentou correlação positiva (r>0,8). Em ambas as espécies, P. beihaiensis esteve localizada principalmente no epitélio gástrico. A infecção foi geralmente leve ou moderada, sem danos aparentes aos hospedeiros, mas em casos de infecção severa, houve reação hemocitária e desorganização de tecidos. As prevalências geralmente altas na região sugerem que as ostras devam ser monitoradas com relação a este patógeno, principalmente em áreas de cultivo.


Subject(s)
Animals , Crassostrea/parasitology , Alveolata/isolation & purification , Alveolata/genetics , Alveolata/pathogenicity , Protozoan Infections, Animal/parasitology , Brazil , Polymerase Chain Reaction
14.
Rev. bras. parasitol. vet ; 26(4): 401-410, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-899305

ABSTRACT

Abstract Crassostrea rhizophorae and C. gasar oysters are cultivated in the northeast region. Perkinsus parasites infect bivalves, and their effects on oysters from tropical regions are poorly understood. This study evaluated the impact of Perkinsus infection on the productive traits of native oysters. Oysters were sampled bimonthly during 7 months, from July 2010 to February 2011, to evaluate growth rate, mortality and shell color patterns (white and dark-gray) (n = 500), and to determine the prevalence and intensity of Perkinsus (n = 152). Perkinsus and Crassostrea species were determined using molecular tools. Results showed that most dark-gray (90%, n = 20) and white (67%, n = 18) oysters were C. gasar and C. rhizophorae, respectively. Oysters showed a high growth rate and moderate cumulative mortality (44%). C. gasar oysters grew better and showed lower mortality and lower incidence of Perkinsus compared to C. rhizophorae. The mean prevalence of Perkinsus was moderate (48%), but the infection intensity was light (2.2). Perkinsosis affected very small oysters (19.4 mm). In conclusion, native oysters, especially C. gasar, have a great potential for culture, mortality is not associated with perkinsosis, and the shell color of oysters can be used to improve selection for spats with better performance.


Resumo Crassostrea rhizophorae e C. gasar são cultivadas na região Nordeste. Parasitas Perkinsus infectam bivalves e seus efeitos em ostras de regiões tropicais são pouco compreendidos. Este estudo avaliou o impacto da infecção por Perkinsus em parâmetros de produção de ostras nativas. Ostras foram coletadas bimestralmente durante 7 meses, de julho de 2010 a fevereiro de 2011, para avaliar crescimento, mortalidade e padrão de coloração da concha (branca e cinza-escura) (n = 500); além da presença e intensidade de Perkinsus (n = 152). Perkinsus e Crassostrea foram identificados por abordagem molecular. Os resultados mostraram que as ostras cinza-escuras (90%, n = 20) e brancas (67%, n = 18) eram C. gasar e C. rhizophorae, respectivamente. As ostras mostraram uma boa taxa de crescimento e mortalidade acumulada moderada (44%). C. gasar cresceu melhor com menor mortalidade e menor incidência de Perkinsus que C. rhizophorae. A prevalência média de Perkinsus foi moderada (48%), mas a intensidade de infecção foi leve (2,2). A perkinsiose afetou ostras pequenas (19,4 mm). Em conclusão, ostras nativas, especialmente C. gasar, têm grande potencial de produção; sem mortalidade associada à perkinsiose; e, a cor da concha pode ser usada para melhorar a seleção de sementes com melhor desempenho.


Subject(s)
Animals , Protozoan Infections, Animal/mortality , Crassostrea/growth & development , Crassostrea/parasitology , Alveolata/physiology , Brazil , Disease Susceptibility
15.
The Korean Journal of Parasitology ; : 399-408, 2017.
Article in English | WPRIM | ID: wpr-203198

ABSTRACT

A survey was performed to know the recent infection status of digenetic trematode metacercariae in clams and oysters from 4 sites in western coastal regions of the Republic of Korea (=Korea). Four species of clams (Mactra veneriformis, Ruditapes philippinarum, Cyclina sinensis, and Saxidomus purpuratus) were collected from Taean-gun, Chungcheongnam-do (Province), Buan-gun (County) and Gochang-gun, Jeollabuk-do, and oysters, Crassostrea gigas, from Shinan-gun, Jeollanam-do were transferred to our laboratory on ice and examined by the artificial digestion method. The metacercariae of Himasthla alincia were detected in 3 species of clams, M. veneriformis, R. philippinarum, and C. sinensis from the 3 surveyed areas. The positive rate and the mean density per clam infected were 98.9% (30.8 metacercariae) in M. veneriformis, 60.0% (5.0) in R. philippinarum, and 96.0% (28.4) in C. sinensis. The positive rate (mean density) of Acanthoparyphium tyosenense metacercariae in M. veneriformis was 50.0% (2.1) from Taean-gun and 70.0% (2.8) from Gochang-gun. The metacercariae of Parvatrema spp. were detected in M. veneriformis and R. philippinarum from Taean-gun and Gochang-gun; the positive rate (mean density) was 63.3% (4,123) and 50.0% (19) in M. veneriformis, and 6.7% (126) and 100% (238) in R. philippinarum from the 2 regions, respectively. The metacercariae of Gymnophalloides seoi were detected in all 30 oysters from Shinan-gun, and their average density per oyster was 646. From the above results, it has been confirmed that more than 3 species of metacercariae are prevalent in clams from the western coastal regions, and G. seoi metacercariae are still prevalent in oysters from Shinan-gun, Jeollanam-do, Korea


Subject(s)
Bivalvia , Crassostrea , Digestion , Ice , Korea , Metacercariae , Methods , Ostreidae , Prevalence , Republic of Korea , Trematoda
16.
Rev. biol. trop ; 64(2): 449-459, abr.-jun. 2016. tab, ilus
Article in Spanish | LILACS | ID: biblio-843289

ABSTRACT

ResumenLa reproducción del ostión americano, Crassostrea virginica se encuentra ligada a la temperatura y la salinidad. Sin embargo el efecto de estos parámetros no ha sido evaluado por sexos y por tallas. En este trabajo se analiza el efecto de la temperatura y la salinidad sobre la reproducción del ostión americano, por sexos separados y por tallas (40-60mm y ≥ 61 mm). Se recolectaron 1 080 ostiones, 90 organismos por mes durante 2011 en la laguna de Tamiahua, Veracruz México. El desarrollo de madurez gonádica se clasificó en tres estadios: gametogénesis, maduros y liberación. La reproducción fue continua en ambos sexos; la gametogénesis presentó máximos entre enero-julio, la madurez entre junio y septiembre y la liberación en enero y febrero, y de septiembre a diciembre. Sólo se presentó correlación significativa entre la temperatura y las hembras de ambas tallas en madurez, pero no en machos. La disminución de la salinidad fue determinante en la liberación de gametos pero sólo para los machos ≥ 61 mm, en machos pequeños y hembras de ambas tallas, este parámetro no tuvo efecto. En este trabajo se puso en evidencia que la temperatura y la salinidad tuvieron efecto diferencial entre tallas y sexos del ostión americano.


AbstractThe American oyster, Crassostrea virginica, is one of the most important economic coastal fishery activities in Mexico. As for other bivalve molluscs, its sustainability is based on healthy populations, and additional information on current reproductive cycles, will reinforce local management strategies. The objective of this study was to evaluate the effect of temperature and salinity on the gonadal development stages in both sexes and in two size groups (40-60 mm and ≥ 61 mm) of C. virginica from Tamiahua Lagoon, Gulf of Mexico. Monthly surveys of 90 organisms were undertaken, for a yearly total of 1 080 oysters sampled from the lagoon in 2011. Both field and laboratory work used standard procedures. Our results showed that reproduction was continuous in both sexes, but some peaks of the reproductive cycle were observed along the year. Peaks registered from January to July were for gametogenesis; those of June and September were for mature individuals; and in January, February, and from September to December, for spawning/spent oysters. Maturity of females of both range sizes was positively correlated with temperature, but not for males. For spawning, spent individuals, males of sizes ≥ 61 mm were positively correlated with salinity, whereas smaller males (40-60 mm) and females of both sizes, did not show any correlation. In this study, we observed that temperature and salinity had a different effect in the reproduction of the American oyster of different sizes and sexes of Tamiahua lagoon. Rev. Biol. Trop. 64 (2): 449-459. Epub 2016 June 01.


Subject(s)
Animals , Male , Female , Crassostrea/physiology , Reproduction/physiology , Seasons , Temperature , Crassostrea/classification , Salinity
17.
Rev. bras. parasitol. vet ; 25(1): 37-45, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-777528

ABSTRACT

Abstract Bivalve culture is of considerable economic and social interest in northeastern (NE) Brazil. The polyculture is an alternative approach to traditional monoculture for reducing the environmental impact of shrimp farming and improving oyster culture. Perkinsus marinus andPerkinsus olseni were found infecting oysters in NE Brazil and can threaten oyster production. This study evaluatedPerkinsus spp. occurrence in Crassostrea gasar during all production stages. Oyster spats were produced in a hatchery and grown in shrimp ponds in Rio Grande do Norte state.Perkinsus spp. were surveyed by Ray’s fluid thioglycollate medium and confirmed by polymerase chain reaction. Prevalence and intensity of infection were determined in oysters until they reached 7 cm. Results showed that the broodstock was already infected by Perkinsus (60%), but the derived spats were Perkinsus-free. Oyster spats acquired Perkinsus infection when transferred to ponds. The prevalence gradually increased in the seven months following placement in ponds (73%), and then decreased to 17% by the tenth month. The infections were initially mild, but intensity increased at the final growth stage. In conclusion, it is possible to produce Perkinsus-free C. gasar oyster spats from infected broodstock, and their culture in shrimp ponds is feasible.


Resumo O cultivo de bivalves é de grande interesse econômico e social no Nordeste (NE) do Brasil. O policultivo é uma alternativa ao monocultivo tradicional de camarões para reduzir o impacto ambiental e melhorar a produção de ostras.Perkinsus marinus e Perkinsus olseni foram identificados infectando ostras no Nordeste do Brasil e representam uma ameaça a produção de ostras. Este estudo avaliou a ocorrência dePerkinsus spp. em Crassostrea gasardurante todas as fases de produção. Sementes de ostras foram produzidas em laboratório e cultivadas em viveiros de camarão no Rio Grande do Norte.Perkinsus spp. foram diagnosticados ​​com o uso do meio de tioglicolato fluido de Ray e confirmado por reação em cadeia da polimerase. A prevalência e intensidade de infecção foram determinadas em ostras até atingirem 7 cm. Os resultados mostraram que os reprodutores encontravam-se infectados porPerkinsus (60%), mas as sementes produzidas estavam livres de Perkinsus. As sementes adquiriram a infecção porPerkinsus quando transferidas para os viveiros. A prevalência aumentou gradualmente nos sete meses após a colocação nos viveiros (73%) e, em seguida, diminuiu para 17% até o décimo mês. As infecções foram inicialmente leves, mas aumentaram até a fase final do crescimento. Em conclusão, é possível produzir sementes de ostras C. gasarlivres de Perkinsus a partir de reprodutores infectados e seu cultivo em viveiros de camarão é viável.


Subject(s)
Animals , Protozoan Infections, Animal/epidemiology , Apicomplexa , Aquaculture/methods , Crassostrea/parasitology , Brazil , Polymerase Chain Reaction , Crustacea/growth & development , Crassostrea/growth & development
18.
Santa Tecla, La Libertad; ITCA Editores; ene. 2016. 28 p. ^c28 cm.ilus., tab., graf..
Monography in Spanish | LILACS, BISSAL | ID: biblio-1223443

ABSTRACT

En El Salvador, el cultivo de Ostra del Pacifico (Crassostrea gigas) es una actividad nueva, ya que en el país se desconocía la reproducción, el manejo de la semilla y el desarrollo del cultivo engorde en las zonas de cultivo. Es por ello que el Centro de Desarrollo de la Pesca y la Acuicultura (CENDEPESCA) juntamente con la cooperación técnica del Gobierno del Japón a través de la Agencia de Cooperación Internacional del Japón (JICA) ha implementado el "Proyecto para el Desarrollo de la Acuicultura de Moluscos en El Salvador" que ha introducido una nueva especie de ostra en El Salvador, la Ostra del Pacifico (Crassostrea gigas) con el objetivo de mejorar la calidad de vida de las comunidades de pescadores, que solamente se ha dedicado a la extracción de los recursos del medio natural, mas no al cultivo directamente a causa de la falta de recursos para la realización de la reproducción de los organismos, adquisición de la semilla e insumos para el desarrollo del cultivo. La Escuela Especializada en Ingeniería ITCA-FEPADE regional La Unión se unió a este esfuerzo y realizó una investigación en cooperación con CENDEPESCA, la cual inició con la siembra de 7,000 semillas en el sistema suspendido de Ostra japonesa, posterior a ello se elaboró un cronograma de trabajo para el control y se desarrollo del crecimiento del cultivo en los 6 meses de duración de la investigación,


In El Salvador, the cultivation of Pacific Oyster (Crassostrea gigas) is a new activity, due to, in the country, the reproduction, the handling of the seed and the development of the fattening crop in the cultivation areas were unknown. That is why the Center for the Development of Fisheries and Aquaculture (CENDEPESCA) together with the technical cooperation of the Government of Japan through the Japan International Cooperation Agency (JICA) has implemented the "Project for the Development of Aquaculture of Mollusks in El Salvador "that has introduced a new species of oyster in El Salvador, the Pacific Oyster (Crassostrea gigas) with the aim of improving the quality of life of the fishing communities, which has only been dedicated to the extraction of the resources of the natural environment, but not to the cultivation directly because of the lack of resources for the realization of the reproduction of the organisms, acquisition of the seed and inputs for the development of the crop. ITCA-FEPADE La Unión joined this effort and carried out an investigation in cooperation with CENDEPESCA, which began with the sowing of 7,000 seeds in the suspended system of Japanese Oyster, after which a schedule of work for the control and development of the growth of the crop in the 6 months of duration of the investigation,


Subject(s)
Ostreidae/growth & development , Aquaculture , Crassostrea/growth & development , Fisheries , Mollusca
19.
Article in English | LILACS, VETINDEX | ID: biblio-875395

ABSTRACT

This study reports the presence of the pathogen Perkinsus marinus, notifiable to the World Organization for Animal Health (Office International des Èpizooties = OIE) in the oyster Crassostrea rhizophorae in southern Bahia via proteomic analysis. We analyzed Crassostrea brasiliana from a long-line cultivation system and C. rhizophorae from an adjacent mangrove in Porto do Campo, Camamu Bay, Bahia, Brazil. The collections (n = 100) were performed in October 2012. In the laboratory, the oysters were measured and opened to remove the meat, which was steeped in dry ice. For extraction of proteins, adaptation of a protocol used for mussels was used, after which separation in the first dimension was taken by isoelectric focusing (IEF). The peptides were transferred to a Mass Spectrometer. The obtained spectra were analyzed with the ProteinLynx Global Server 4.2 software tool and also by MASCOT (Matrix Science) and compared to the databases of the SWISSPROT and NCBI, respectively. The identification was evidenced by beta-tubulin, Perkinsus marinus ATCC 50983 and protein homology code in the database NCBI = gi | 294889481. This is the first record of P. marinus in Bahia and the fourth in Brazil.(AU)


Este estudo relata a presença do patógeno Perkinsus marinus, de notificação obrigatória à Organização Internacional de Epizootias (OIE) na ostra Crassostrea rhizophorae no sul da Bahia, via análise proteômica. Foram analisadas as ostras Crassostrea brasiliana de um cultivo em espinhel e C. rhizophorae de um manguezal adjacente, na localidade de Porto do Campo, Baía de Camamu, Bahia. As coletas (n = 100) foram efetuadas em outubro de 2012. Em laboratório, as ostras foram medidas e abertas para a retirada da carne, que foi macerada em gelo seco. Para a extração das proteínas, foi adotada a adaptação de um protocolo utilizado para mexilhões, após o que foi realizada a separação na primeira dimensão, por focalização isoelétrica (IEF). Os peptídeos foram transferidos para um Espectrômetro de Massas. Os espectros obtidos foram analisados no software ProteinLynx Global Server 4.2 e também pela ferramenta MASCOT (Matrix Science) e comparados com os bancos de dados do SWISSPROT e do NCBI, respectivamente. A identificação foi evidenciada por meio da beta-tubulina, homologia Perkinsus marinus ATCC 50983 e código da proteína no banco de dados NCBI = gi|294889481. Este é o primeiro registro de P. marinus na Bahia e o quarto no Brasil.(AU)


Subject(s)
Animals , Crassostrea/parasitology , Proteomics , Protozoan Infections, Animal/diagnosis , Mass Spectrometry/veterinary , Ostreidae/parasitology
20.
Braz. j. vet. res. anim. sci ; 53(2): 191-198, 2016. mapas, tab, graf
Article in English | LILACS | ID: lil-789919

ABSTRACT

This study investigated the infection of Perkinsus beihaiensis (Perkinsozoa) in the oyster Crassostrea rhizophorae, both from a long-line cultivation system and from a nearby intertidal zone of mangrove, both in the state of Bahia, northeastern Brazil. The collections were performed in October and November 2012, and in January 2013. The oysters (n = 300) were measured, examined macroscopically for signs of infection and then submitted to the following laboratory techniques: histology, Ray"s fluid thioglycollate medium assay (RFTM), polymerase chain reaction (PCR) and sequencing, which confirmed the identification of the pathogen. Histological and RFTM analyses showed, respectively, a mean prevalence of 93.3% and of 69%. The infection was usually mild or very mild. There was no significant difference (p > 0.05) between the environments in terms of infection prevalence or severity. This is the first record of P. beihaiensis in the state of Bahia and the second in oysters from Brazil and South America...


Foi investigada a infecção de Perkinsus beihaiensis (Perkinsozoa) na ostra Crassostrea rhizophorae em um sistema de cultivo do tipo espinhel e em um estoque natural de ostras no manguezal adjacente ambos localizados no estado da Bahia, Nordeste do Brasil. As colheitas foram realizadas em outubro e novembro de 2012 e em janeiro de 2013. As ostras (n = 300) foram medidas, examinadas macroscopicamente quanto a sinais da infecção e submetidas às técnicas laboratoriais: histologia, ensaio em meio de cultivo de tioglicolato de Ray (RFTM), reação em cadeia da polimerase (PCR) e sequenciamento, que confirmou a identificação do patógeno. As análises histológicas e o RFTM mostraram, respectivamente, prevalência média de 93,3% e de 69%. A infecção foi geralmente leve ou muito leve. Não houve diferença significativa (p > 0,05) entre os ambientes em termos de prevalência ou severidade da infecção. Este é o primeiro registro de P. beihaiensis no estado da Bahia e o segundo em ostras do Brasil e América do Sul...


Subject(s)
Animals , Crassostrea/microbiology , Protozoan Infections/diagnosis , Bivalvia/microbiology , Polymerase Chain Reaction/veterinary , Histological Techniques/veterinary , Clinical Laboratory Techniques/veterinary
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