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Registros recuperados: 112
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Cold storage of Pacific oysters out of water: biometry, intervalval water and sensory assessment ArchiMer
Buzin, Florence; Baudon, Violaine; Cardinal, Mireille; Barille, Laurent; Haure, Joel.
Due to the important economic activity of oyster production in France, microalgal toxic events represent a significant constraint for shellfish farmers who face closures of bivalve production-sites. The frequency of closures of 3 weeks or less represents half of the total closures along the French coasts. Cold storage could be a simple and affordable solution for temporary and short-term storage before commercialisation. A stock of marketable Pacific oyster Crassostrea gigas was therefore stored during 22 days in non-immersed conditions at 3 degrees C with 100% humidity. At the end of the experiment, the oyster mortality rate remained at a low level of less than 3.5%. The sensory attributes, odour, appearance, texture and flavour, did not show significant...
Tipo: Text Palavras-chave: Quality control; Refrigeration; Sensory evaluation; Shelf life; Shellfish.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00041/15245/12840.pdf
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Three-year study to assess human enteric viruses in shellfish ArchiMer
Le Guyader, Soizick; Haugarreau, Larissa; Miossec, Laurence; Dubois, Eric; Pommepuy, Monique.
The main pathogenic enteric viruses able to persist in the environment, such as hepatitis A virus (HAV), Norwalk-like virus (NLV), enterovirus (EV), rotavirus (RV), and astrovirus (AV), were detected by reverse transcription-PCR and hybridization in shellfish during a 3-year study. Oyster samples (n = 108), occasionally containing bacteria, were less frequently contaminated, showing positivity for AV (17%), NLV (23%), EV (19%), and RV (27%), whereas mussel samples, collected in areas routinely impacted by human sewage, were more highly contaminated: AV (50%), HAV (13%), NLV (35%), EV (45%), and RV (52%). Sequences obtained from HAV and NLV amplicons shelved a great variety of strains, especially for NLV (strains close to Mexico, Snow Mountain Agent, or...
Tipo: Text Palavras-chave: Molecular technique; Seasonal variation; Human pathology; Viral contamination; Shellfish; Enteric virus.
Ano: 2000 URL: https://archimer.ifremer.fr/doc/00507/61879/65953.pdf
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Evidence of the presence of viral shellfish contamination in shellfish after short rainfall events ArchiMer
Le Saux, Jean-claude; Serais, Ophelie; Krol, Joanna; Parnaudeau, Sylvain; Salvagnac, P.; Delmas, G.; Cicchelero, V.; Claudet, J.; Pothier, P.; Balay, K.; Fiandrino, Annie; Pommepuy, Monique; Le Guyader, Soizick.
Infectious diseases linked to the consumption of raw shellfish have long been identified. Over the past century, various strategies have been set up in shellfish growing areas throughout the world to guarantee the sanitary quality of shellfish and to protect consumers. However despite sanitary improvements, human enteric viruses - especially Hepatitis A virus and norovirus– have been found to be associated with shellfish outbreaks. A recent example demonstrated the impact of storm events. Following heavy rain and sewage overflow, shellfish beds were contaminated and the shellfish from them were marketed after depuration. However, since viruses persist longer than fecal contamination indicator bacteria, several clusters of gastroenteritis cases were...
Tipo: Text Palavras-chave: Virus; Shellfish; Contamination events.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/00066/17736/15257.pdf
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Use of rotavirus virus-like particles as surrogates to evaluate virus persistence in shellfish ArchiMer
Loisy, Fabienne; Atmar, R; Le Saux, Jean-claude; Cohen, J; Caprais, Marie-paule; Pommepuy, Monique; Le Guyader, Soizick.
Rotavirus virus-like particles (VLPs) and MS2 bacteriophages were bioaccumulated in bivalve mollusks to evaluate viral persistence in shellfish during depuration and relaying under natural conditions. Using this nonpathogenic surrogate virus, we were able to demonstrate that about 1 log(10) of VLPs was depurated after 1 week in warm seawater (22 degrees C). Phage MS2 was depurated more rapidly (about 2 log(10) in 1 week) than were VLPs, as determined using a single-compartment model and linear regression analysis. After being relayed in the estuary under the influence of the tides, VLPs were detected in oysters for up to 82 days following seeding with high levels of VLPs (concentration range between 10(10) and 10(9) particles per g of pancreatic tissue)...
Tipo: Text Palavras-chave: Seawater; Viral diseases; Bioaccumulation; Depuration; Contamination; Model; Pancreas; Regression analysis; Shellfish; Phages; Virus.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/2005/publication-1233.pdf
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Bilan 2004 du réseau REPAMO - Réseau national de surveillance zoosanitaire des mollusques marins ArchiMer
Garcia, Celine; Arzul, Isabelle; Chollet, Bruno; Francois, Cyrille; Goubet, Anne; Joly, Jean-pierre; Miossec, Laurence; Robert, Maeva; Cuvelier, Nicolas; Lefebvre, Alain; Le Gagneur, Eric; Ropert, Michel; Mouillard, Gilbert; Gerla, Daniel; Le Gal, Dominique; Rocher, Gregory; Langlade, Aime; Bedier, Edouard; Nourry, Max; Martin, Jean-louis; Costantini, Louis; Masson, Jean-claude; Martin, Anne-genevieve.
Created in 1986, the REPAMO network (Network of mollusc pathology), is a national zoosanitary surveillance network of shellfish health status along the French coasts. Its activities are in keeping with two European Directives, 91 /67/EEC and 95/70/EC and are a patt of the institutional tasks ofIfremer. The aims of the network are to prevent the introduction and spread of exotic pathogens and to survey the evolution of notifiable pathogens already present in France. The network focused on the survey of listed diseases (bonamiosis and marteiliosis of flat oyster) in two areas under agreement process (Banc de Granville and zone X). In 2004, no sample couId be analysed to these two areas because of the difficulty to obtain flat oysters (sparse oyster beds,...
Tipo: Text Palavras-chave: Réseau; Surveillance; Pathologie; Mollusques; Coquillages; Etat de santé; Network; Surveillance; Pathology; Molluscs; Shellfish; Health status.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/00086/19702/17343.pdf
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A Feedback Mechanism to Control Apoptosis Occurs in the Digestive Gland of the Oyster Crassostrea gigas Exposed to the Paralytic Shellfish Toxins Producer Alexandrium catenella ArchiMer
Rolland, Jean-luc; Medhioub, Walid; Vergnes, Agnes; Abi-khalil, Celina; Savar, Veronique; Abadie, Eric; Masseret, Estelle; Amzil, Zouher; Laabir, Mohamed.
To better understand the effect of Paralytic Shellfish Toxins (PSTs) accumulation in the digestive gland of the Pacific oyster, Crassostrea gigas, we experimentally exposed individual oysters for 48 h to a PSTs producer, the dinoflagellate Alexandrium catenella. In comparison to the effect of the non-toxic Alexandrium tamarense, on the eight apoptotic related genes tested, Bax and BI.1 were significantly upregulated in oysters exposed 48 h to A. catenella. Among the five detoxification related genes tested, the expression of cytochrome P450 (CYP1A) was shown to be correlated with toxin concentration in the digestive gland of oysters exposed to the toxic dinoflagellate. Beside this, we observed a significant increase in ROS production, a decrease in...
Tipo: Text Palavras-chave: Shellfish; Toxin; Biomarker; Expression; Phytoplankton.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00225/33606/32003.pdf
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Validity of Escherichia coli, enterovirus, and F-specific RNA bacteriophages as indicators of viral shellfish contamination ArchiMer
Miossec, Laurence; Le Guyader, Soizick; Pelletier, Dominique; Haugarreau, Larissa; Caprais, Marie-paule; Pommepuy, Monique.
The sanitary classification of harvesting areas for bivalve mollusks in France is based on the level of Escherichia Coli contamination detected in shellfish meat, as defined in EC Directive 91/492 EEC. However, outbreaks of gastroenteritis or hepatitis after consumption of shellfish meeting current bacteriological standards suggest that E. coli is a poor indicator of viral contamination. The purpose of this study was to assess the adequacy of enterovirus and F-specific RNA bacteriophages as new indicators of human enteric viruses. Shellfish were sampled over a 37-mo period to characterize microbial contamination in two coastal areas subjected to different sewage contamination inputs. Contamination by E. coli, F-specific RNA bacteriophages (F+ RNA) and...
Tipo: Text Palavras-chave: Indicator; Escherichia coli; F specific RNA bacteriophages; Enteric viruses; Viral contamination; Shellfish.
Ano: 2001 URL: https://archimer.ifremer.fr/doc/00000/10006/7794.pdf
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Surveillance des phycotoxines dans les coquillages ArchiMer
Nicolas, Marina; Belin, Catherine; Favre, Pauline; Rudloff, Laurence.
This paper presents the French national system for monitoring three groups of marine biotoxins regulated in shellfish, implemented firstly in marine production areas by the REPHY REPHYTOX network of IFREMER and secondly at distribution level through the network of laboratories accredited by the Directorate General for Food within the framework of official controls. The European regulations, the nature of the shellfish toxins, and analytical methods used are presented. The sampling procedures and strategy, as well as the results obtained by each of the two systems mentioned, are presented and discussed.
Tipo: Text Palavras-chave: Phycotoxines; Coquillages; Toxines lipophiles; ASP; PSP; Surveillance; Phycotoxins; Shellfish; Lipophilic toxins; ASP; PSP; Surveillance.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00393/50407/51123.pdf
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Quantification of Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae in French Mediterranean coastal lagoons ArchiMer
Cantet, Franck; Hervio-heath, Dominique; Caro, A; Le Mennec, Cecile; Monteil, Caroline; Quemere, Catherine; Jolivet-gougeon, Anne; Colwell, Rita R.; Monfort, Patrick.
Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae are human pathogens. Little is known about these Vibrio spp. in the coastal lagoons of France. The purpose of this study was to investigate their incidence in water, shellfish and sediment of three French Mediterranean coastal lagoons using the most probable number-polymerase chain reaction (MPN-PCR). In summer, the total number of V. parahaemolyticus in water, sediment, mussels and clams collected from the three lagoons varied from 1 to >1.1 x 10.3 MPN/l, 0.09 to 1.1 x 10.3 MPN/ml, 9 to 210 MPN/g and 1.5 to 2.1 MPN/g, respectively. In winter, all samples except mussels contained V. parahaemolyticus, but at very low concentrations. Pathogenic (tdh- or trh2-positive) V. parahaemolyticus were...
Tipo: Text Palavras-chave: Vibrio; Lagoons; Shellfish; Water; Sediment; Human pathogen.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00148/25890/23889.pdf
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Modeling of Faecal Contamination in Water from Catchment to Shellfish Growing Area ArchiMer
Bougeard, Morgane; Le Saux, Jean-claude; Perenne, Nicolas; Le Guyader, Soizick; Pommepuy, Monique.
During rainstorms, watersheds can introduce large amounts of faecal pollution into the rivers and sea, leading to shellfish contamination. In this study, we assessed Escherichia coli fluxes from a catchment, and their impact on estuarine water quality, using two assembled models. For the catchment, the agro-hydrological model SWAT was implemented integrating land uses, soil, topography, rainfall and other climatic data on Daoulas watershed (France). Initially, the SWAT model was calibrated and validated for river flow rates, and results were found satisfactory. Subsequently, different faecal contamination sources were integrated into the model: point sources (WWTP discharges into rivers) and non-point sources (manure spreading on fields). During rainfall...
Tipo: Text Palavras-chave: Modeling; SWAT; MARS; E. coli; Shellfish; Catchment; Estuary.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/00066/17748/15270.pdf
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Technical paper on Toxicity Equivalency Factors for Marine Biotoxins Associated with Bivalve Molluscs ArchiMer
FAO/WHO.
World bivalve molluscs production (capture + aquaculture) has been increasing substantially in the last fifty years, going from nearly one million tonnes in 1950 to about 15 million tonnes in 2012. Being filter feeders, bivalves utilise natural plankton and detritus as feed and do not require artificial feeds. But this filter feeding nature is also the reason for the requirement of strict environmental hygiene to produce bivalves safe for human consumption. They tend to concentrate microorganisms, toxins and chemicals from the environment and therefore, their safety management requires stringent sanitary measures to ensure consumer protection. Following the request of Codex Committee on Fish and Fishery Products (CCFFP), FAO/WHO agreed to develop a...
Tipo: Text Palavras-chave: Toxicity; Shellfish; Risk assessment; Fisheries; Fishery products; Consumer protection; Food safety; Aquatic environment.
Ano: 2016 URL: http://archimer.ifremer.fr/doc/00360/47124/47058.pdf
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DIPNET - A European project to evaluate disease interactions and pathogen exchange between farmed and wild aquatic animal population fish, shellfish and crustaceans ArchiMer
Miossec, Laurence; Garseth, A. H.; Midtlyng, P. J.; Raynard, R.; Peeler, E.; De Bals, I..
DIPNET (Disease Interaction and Pathogen exchange Network) is a co-ordination action funded under the UE Framework programme 6 priority 8 Scientific Support to Policy (SSP). The principal objective of DIPNET is to increase scientific knowledge of the potential transfer of pathogens and diseases between wild and farmed fish and shellfish populations. DIPNET started in October 2004 and is a 2 year project. The project is organized in four work packages. Work package (WP) 1 is focused on a literature review of disease interactions and pathogen exchange between farm and wild aquatic animals. This analysis includes both published and unpublished literature. The work covers a wide range of habitats and species within Europe and, where relevant, world-wide. WP1...
Tipo: Text Palavras-chave: DIPNET; Crustaceans; Shellfish; Fish; Epidemiology; Risk assessment; Diseases; Transfer of pathogens.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/2005/acte-3325.pdf
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Surveillance des risques biologiques liés à la consommation de coquillages en France ArchiMer
Vaillant, Véronique; Jourdan-da Silva, Nathalie; Quilici, Marie-laure; Couturier, Elisabeth; Le Guyader, Soizick; Delmas, Gilles; Le Saux, Jean-claude.
Shellfish filter large volumes of water to meet their nutritional requirements and thus ingest phytoplankton, but also concentrate microorganisms naturally present in water (vibrios, phycotoxins) or of fecal origin (enteric viruses, enterobacteria, protozoan). The analysis of data from systems contributing to the surveillance of foodborne illnesses associated with shellfish consumption and from published outbreak investigations shows that, in France, foodborne illnesses associated with shellfish consumption are mainly of viral origin, mostly due to norovirus followed by hepatitis A virus. The risk linked to phycotoxins appears low and the one related to enterobacteria and vibrios very low. The mandatory notification (MN) of foodborne outbreaks remains the...
Tipo: Text Palavras-chave: Toxi-infections alimentaires; Coquillages; Phycotoxines; Risques biologiques; Surveillance épidémiologique; Déclaration obligatoire; France; Foodborne illnesses; Shellfish; Phycotoxins; Biological risks; Epidemiological surveillance; Mandatory notification; France.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00092/20362/18023.pdf
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Possible relation between a winter epidemic of acute gastroenteritis in France and viral contamination of shellfish ArchiMer
Miossec, Laurence; Le Guyader, Soizick; Haugarreau, Larissa; Comps, Marie-annick; Pommepuy, Monique.
Several outbreaks of gastroenteritis related to the consumption of shellfish (frequently eaten raw) have been reported in different parts of the world. In Europe, hum an calicivirus infections may have been involved in winter outbreaks in recent years, although there is little evidence confirming such viral contamination in shellfish. This study presents the first results of a field survey on viral contamination in two shelllish harvesting areas along the French Mediterranean coast. The first, consisting mainly of oyster beds, was c1assified in category A, as determined by fecal coliform counts in shellfish (European Community Directive 91/492), and the second, a mussel bed, was c1assified in category C. Shelllish samples were collected monthly between...
Tipo: Text Palavras-chave: Shellfish; Viral contamination; Enterovirus; Human calicivirus; Rotavirus; Astrovirus; Fecal coliforms; Gastroenteritis.
Ano: 1998 URL: https://archimer.ifremer.fr/doc/00001/11257/7802.pdf
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Rapport de mission AQUANET Forum, Fredericton, New Brunswick, Canada, 16- 18 juin 2003 & visite à la station biologique de St Andrews, New Brunswick, Canada, 19 juin 2003 ArchiMer
Mazurie, Joseph.
Among the Excellence Centers developed to federate the Canadian research, Aquanet deals with marine and freshwater aquaculture. An interdisciplinary science forum was held at Fredericton, New Brunswick, Canada, in order to analyse the state of the fish and shellfish aquaculture sector and propose orientations for the future researches. Around 30 Canadian scientists and professionnals (a Norvegian and a French scientist invited) attended the meeting. A visit at the biological station and Huntsman marine center at Saint-Andrews, New Brunswick, concluded the mission
Tipo: Text Palavras-chave: Canada; Nouveau Brunswick; Pisciculture; Conchyliculture; Aquaculture; Programmation Recherche; Aquanet; Canada; New Brunswick; Fish; Shellfish; Aquaculture; Research; Aquanet.
Ano: 2003 URL: https://archimer.ifremer.fr/doc/00681/79316/81824.pdf
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Development of genomic probes for detection of hepatitis A virus and enteroviruses in shellfish ArchiMer
Apaire, M; Leguyader, F; Besse, B; Billaudel, S.
The development of molecular biology techniques has modified research procedures for certain viruses, particularly hepatitis A virus (HAV) and enteroviruses. Accordingly, we designed cDNA and RNA genomic probes to detect viruses in shellfish in the environment. Better sensitivity was noted with RNA than cDNA probes: only 17/83 shellfish samples were positive with HAV and enterovirus DNA probes, where as 42/83 were positive with HAV and enterovirus RNA probes.
Tipo: Text Palavras-chave: Mollusca; Enterovirus; Hepatitis A virus; Picornaviridae; RNA probes; DNA probes; Seafood; Biology; Sensors; DNA; RNA; Viruses; Detection; Marine molluscs; Shellfish.
Ano: 1992 URL: http://archimer.ifremer.fr/doc/1992/acte-1613.pdf
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Health risk assessment related to pinnatoxins in French shellfish ArchiMer
Arnich, Nathalie; Abadie, Eric; Delcourt, Nicolas; Fessard, Valérie; Fremy, Jean-marc; Hort, Vincent; Lagrange, Emmeline; Maignien, Thomas; Molgó, Jordi; Peyrat, Marie-bénédicte; Vernoux, Jean-paul; Mattei, César.
Pinnatoxins (PnTXs) are a group of emerging marine biotoxins produced by the benthic dinoflagellate Vulcanodinium rugosum, currently not regulated in Europe or in any other country in the world. In France, PnTXs were detected for the first time in 2011, in mussels from the Ingril lagoon (South of France, Mediterranean coast). Since then, analyses carried out in mussels from this lagoon have shown high concentrations of PnTXs for several months each year. PnTXs have also been detected, to a lesser extent, in mussels from other Mediterranean lagoons and on the Atlantic and Corsican coasts. In the French data, the main analog is PnTX G (low levels of PnTX A are also present in some samples). No cases of PnTXs poisoning in humans have been reported so far in...
Tipo: Text Palavras-chave: Pinnatoxins; Shellfish; Emerging marine biotoxins; Risk assessment.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00619/73105/72236.pdf
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Relance de l'huître plate. Rapport d'avancement des travaux. Année 1992 ArchiMer
Martin, Anne-genevieve.
A revival program for the European flat oyster Ostrea edulis was initiated in Brittany in 1984 and funded by regional and national agencies. Since then, the research programs were carried out and the 1992 results are presented in this report. Disease status and spat settlement trends are described within each breeding area as well as advances in management practices and genetic research.
Tipo: Text Palavras-chave: Bivalves; Ostrea edulis; Bonamia ostreae; Marteilia refringens; Epidemiologie; Pathologie; Génétique; Echantillonnage; Elevage; Shellfish; Ostrea edulis; Bonamia ostreae; Marteilia refringens; Epidemiology; Pathology; Genetic; Sampling; Breeding.
Ano: 1993 URL: http://archimer.ifremer.fr/doc/00427/53823/54814.pdf
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Small-scale spatial variability of food partitioning between cultivated oysters and associated suspension-feeding species, as revealed by stable isotopes ArchiMer
Dubois, Stanislas; Orvain, Francis; Marin Leal, Julio César; Ropert, Michel; Lefebvre, Sébastien.
Oyster culture structures support a host of epibionts belonging to the same suspension-feeding guild, which are considered to be potential competitors for food with cultivated oysters. In an intertidal shellfish ecosystem on the northern French coast, an approach based on stable isotopes (C-13 and N-15) was used to investigate intra- and interspecific food resource partitioning among cultivated oysters and the main associated wild sessile epibionts such as polychaetes, barnacles, mussels and ascidians. The main objective of the present study was to determine inter- and intraspecific food partitioning, along with small-scale spatial variability, within the guild of suspension feeders. We demonstrated that interspecific competition was limited among...
Tipo: Text Palavras-chave: Trophic plasticity; Spatial variability; Stable isotopes; Sessile epibionts; Oysters; Shellfish.
Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-2626.pdf
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La surveillance des phycotoxines dans les coquillages du milieu marin. Le réseau REPHY : objectifs, stratégies, et principaux résultats ArchiMer
Belin, Catherine.
The surveillance of phycotoxins in marine shellfish. The REPHY network: objectives, strategies and primary results One of the objectives of REPHY (network for phytoplankton and phycotoxin surveillance) is to monitor toxin-producing micro-algae species in the marine environment that are likely to accumulate in seafood products, and to screen for these toxins in shellfish. This surveillance is undertaken in the framework of the European regulations. Three groups of toxins are thus monitored and are associated with three genera of toxic phytoplankton: (i) Dinophysis, a producer of the okadaic acid (with diarrhoeic effects) and pectenotoxin families of toxins; in the same group of so-called “lipophilic toxins”, two other families of regulated toxins are...
Tipo: Text Palavras-chave: Santé; Surveillance; Phytoplancton; Phycotoxines; Coquillages; Milieu marin; Health; Surveillance; Phytoplankton; Phycotoxins; Shellfish; Marine environment.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00449/56089/57623.pdf
Registros recuperados: 112
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