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Registros recuperados: 54 | |
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Segarra, Amelie; Mauduit, Florian; Faury, Nicole; Trancart, Suzanne; Degremont, Lionel; Tourbiez, Delphine; Haffner, Philippe; Barbosa-solomieu, Valerie; Pepin, Jean-francois; Travers, Marie-agnes; Renault, Tristan. |
Background: Massive mortality outbreaks affecting Pacific oyster (Crassostrea gigas) spat in various countries have been associated with the detection of a herpesvirus called ostreid herpesvirus type 1 (OsHV-1). However, few studies have been performed to understand and follow viral gene expression, as it has been done in vertebrate herpesviruses. In this work, experimental infection trials of C. gigas spat with OsHV-1 were conducted in order to test the susceptibility of several bi-parental oyster families to this virus and to analyze host-pathogen interactions using in vivo transcriptomic approaches. Results: The divergent response of these oyster families in terms of mortality confirmed that susceptibility to OsHV-1 infection has a significant... |
Tipo: Text |
Palavras-chave: Interactions; Ostreid herpesvirus 1; Gene expression; Susceptibility; Crassostrea gigas. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00199/31029/29431.pdf |
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Parizadeh, Leila; Tourbiez, Delphine; Garcia, Celine; Haffner, Philippe; Degremont, Lionel; Le Roux, Frederique; Travers, Marie-agnes. |
Although vibrios are frequently associated with marine organisms mortality outbreaks, knowledge on their ecology and pathogenicity is sparse, thus limiting disease management and prophylactic strategies. Here, we investigated V. aestuarianus infection onset and progression in the wild, taking advantage of a “claire” pond: a semi‐closed system with limited seawater renewal, theoretically more adapted to disease transmission. We showed a positive association of the bacteria with oysters, which can constitute a reservoir for the bacteria in the winter. Moreover, passage through oysters was found to be necessary for experimental disease reproduction as vibrios shedding from diseased oysters has higher infectivity than from in vitro grown. We next developed an... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00446/55761/57423.pdf |
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Bechemin, Christian; Soletchnik, Patrick; Polsenaere, Pierre; Le Moine, Olivier; Pernet, Fabrice; Protat, Martin; Fuhrmann, Marine; Quere, Claudie; Goulitquer, Sophie; Corporeau, Charlotte; Lapegue, Sylvie; Travers, Marie-agnes; Morga, Benjamin; Garrigues, Manon; Garcia, Celine; Haffner, Philippe; Dubreuil, Christine; Faury, Nicole; Baillon, Laury; Baud, Jean-pierre; Renault, Tristan. |
Mass mortality outbreaks (90-100%) in both juvenile and adult blue mussels were reported in 2014 along the Pertuis Charentais area of the French Atlantic coast. A series of studies were carried out to learn more about the phenomenon through detecting pathogens, describing environmental conditions and establishing the physiological status of the animals. Bacteria identif ied as belonging to the V. splendidus species were detected in dying mussels and seem able to cause mortality in blue mussels in the laboratory. Unusual environmental conditions (large amounts of fresh water, re-suspension of sediments during a series of storms, and a high renewal rate of specific water masses in Brittany’s Pertuis area) may be partially responsible for sparking the phenomen |
Tipo: Text |
Palavras-chave: Mortalités; Moules; Pertuis Charentais; Vibrio splendidus; Environnement; Mortality; Mussels; Pertuis Charentais; Vibrio splendidus; Environment. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00312/42343/41682.pdf |
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Segarra, Amelie; Faury, Nicole; Haffner, Philippe; Pepin, Jean-francois; Tourbiez, Delphine; Trancart, Suzanne; Travers, Marie-agnes; Renault, Tristan. |
Le premier cas d'infection à virus de type herpès a été rapporté en 1972, aux Etats Unis, chez l'huître américaine, Crassostrea virginica (Farley et al, 1972). A partir de 1991, des mortalités massives associées à la détection de virus de type herpes ont été observées chez plusieurs espèces de bivalves marins, à différents stades de développement (essentiellement chez les larves et le naissain) et dans différentes régions du monde. Sur la base d’observation en microscopie électronique à transmission, ces virus présentaient des caractéristiques morphologiques identiques à celles des Herpesvirus (Roizman, 1982). Les connaissances acquises concernant la taille, la structure et le séquençage du génome d’un virus infectant les larves d’huîtres creuses en... |
Tipo: Text |
Palavras-chave: Herpès virus OsHV-1; Expression gènes; Huître creuse; Crassostrea gigas. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00195/30627/29076.pdf |
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Mersni-achour, Rachida; Ben Cheikh, Yosra; Pichereau, Vianney; Doghri, Ibtissem; Etien, Cedric; Degremont, Lionel; Saulnier, Denis; Fruitier-arnaudin, Ingrid; Travers, Marie-agnes. |
Vibrio tubiashii is a marine pathogen isolated from larval and juvenile bivalve molluscs causing bacillary necrosis. Recent studies demonstrated the isolation of this species in a French experimental hatchery/nursery affecting Crassostrea gigas spat in 2007. Here, using larvae of C. gigas as an interaction model, we showed that the French V. tubiashii is virulent to larvae and can cause bacillary necrosis symptoms with a LD50 about 2.3 × 103 cfu ml-1 after 24 h. Moreover, complete or GP- HPLC fractionated extracellular products (ECPs) of this strain appeared toxic to larvae. MS-MS analysis of the different ECPs fractions revealed the existence of an extracellular metalloprotease and other suspected virulence factors. This observation is also supported by... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00252/36367/34907.pdf |
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Travers, Marie-agnes; Mersni Achour, Rachida; Haffner, Philippe; Tourbiez, Delphine; Cassone, Anne-laure; Morga, Benjamin; Doghri, Ibtissem; Garcia, Celine; Renault, Tristan; Fruitier-arnaudin, Ingrid; Saulnier, Denis. |
Nine dominant bacterial isolates were obtained from different batches of Crassostrea gigas spat experiencing high mortality rates in a French experimental hatchery/nursery in 2007. Using phenotypic analysis combined with multilocus sequence analysis, the isolates were shown to be genetically close to the Vibrio tubiashii type strain. Based on (1) analyses of the recA gene sequences; (2) the results of DNA–DNA hybridization assays between 07/118 T2 (LMG 27884 = CECT 8426), which is a representative strain, and the V. tubiashii type strain (69%); and (3) phenotypic traits, the bacteria were classified in a group close to American V. tubiashii strain. Its virulence (70% of mortalities) and the toxicity of the extracellular products of 07/118 T2 was... |
Tipo: Text |
Palavras-chave: Crassostrea gigas Pathogenicity Extracellular products Polyphasic approach; Real time PCR. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00189/30028/28743.pdf |
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Mersni Achour, Rachida; Imbert-auvray, Nathalie; Huet, Valerie; Ben Cheick, Yosra; Faury, Nicole; Doghri, Ibtissem; Rouatbi, Sonia; Bordenave, Stéphanie; Travers, Marie-agnes; Saulnier, Denis; Fruitier-arnaudin, Ingrid. |
Extracellular products (ECPs) of the French V. tubiashii strain 07/118 T2 were previously reported to be toxic for the Pacific oyster Crassostrea gigas. In this study we now assessed host cellular immune responses and bacterial potential effectors by which these ECPs can be associated with host damages. The adhesion capacity (28% inhibition) and phagocytosis ability (56% inhibition) of oyster hemocytes were the main functions affected following in vitro contact between hemocytes and V. tubiashii ECPs. This may be linked to the demonstration of the capability of ECPs to cleave various cellular substrates as oyster collagen. Moreover, a strong metalloproteolytic activity was recorded with general (azocasein) and specific (ADAM) substrates and characterized... |
Tipo: Text |
Palavras-chave: ECPs; Oyster immune responses; Thermolysin-metalloprotease; Mass spectroscopy; ADAM substrate; Vibrio. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00211/32203/30642.pdf |
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Ben Cheikh, Yosra; Travers, Marie-agnes; Morga, Benjamin; Godfrin, Yoann; Rioult, Damien; Le Foll, Franck. |
Bacterial isolates were obtained from mortality events affecting Mytilus edulis and reported by professionals in 2010-2013 or from mussel microflora. Experimental infections allowed the selection of two isolates affiliated to V. splendidus/V. hemicentroti type strains: a virulent 10/068 1T1 (76,6% and 90% mortalities in 24h and 96h) and an innocuous 12/056 M24T1 (0% and 23,3% in 24h and 96h). These two strains were GFP-tagged and validated for their growth characteristics and virulence as genuine models for exposure. Then, host cellular immune responses to the microbial invaders were assessed. In the presence of the virulent strain, hemocyte motility was instantaneously enhanced but markedly slowed down after 2h exposure. By contrast, hemocyte velocity... |
Tipo: Text |
Palavras-chave: Innate immunity; Molluscs; Cell-mediated immune response; Bacterial infections; Green fluorescent protein. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00302/41336/40522.pdf |
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Azema, Patrick; Lamy, Jean-baptiste; Boudry, Pierre; Renault, Tristan; Travers, Marie-agnes; Degremont, Lionel. |
Background In France, two main diseases threaten Pacific oyster production. Since 2008, Crassostrea gigas spat have suffered massive losses due to the ostreid herpesvirus OsHV-1, and since 2012, significant mortalities in commercial-size adults have been related to infection by the bacterium Vibrio aestuarianus. The genetic basis for resistance to V. aestuarianus and OsHV-1 and the nature of the genetic correlation between these two traits were investigated by using 20 half-sib sire families, each containing two full-sib families. For each disease, controlled infectious challenges were conducted using naïve oysters that were 3 to 26 months old. In addition, siblings were tested under field, pond and raceway conditions to determine whether laboratory... |
Tipo: Text |
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Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00372/48350/48518.pdf |
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Benabdelmouna, Abdellah; Saunier, Alice; Ledu, Christophe; Travers, Marie-agnes; Morga, Benjamin. |
In the context of the abnormal mass mortality of mussels in France since 2014, Flow CytoMetry (FCM) was used in 2015 and 2016 to study the DNA content and cell cycle characteristics of hemic circulating cells collected from 2000 mussels. The mussels were sampled from 12 wild and cultivated blue mussels stocks distributed along the French Atlantic coast from the south Brittany to Pertuis Charentais areas. During these surveys, various genetic abnormalities were frequently detected, and ploidy characteristics revealed contrasting profiles that corresponded to respective contrasting sanitary status, i.e. healthy mussels with high cytogenetic quality (HCQ) versus diseased mussels with low cytogenetic quality (LCQ). In the present work, FCM and hemocytology... |
Tipo: Text |
Palavras-chave: Mussels; Hemocytes; Flow cytometry; Hemocytology; Cytogenetic quality; Neoplasia. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00455/56623/58443.pdf |
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Macneil, M. Aaron; Chapman, Demian D.; Heupel, Michelle; Simpfendorfer, Colin A.; Heithaus, Michael; Meekan, Mark; Harvey, Euan; Goetze, Jordan; Kiszka, Jeremy; Bond, Mark E.; Currey-randall, Leanne M.; Speed, Conrad W.; Sherman, C. Samantha; Rees, Matthew J.; Udyawer, Vinay; Flowers, Kathryn I.; Clementi, Gina; Valentin-albanese, Jasmine; Gorham, Taylor; Adam, M. Shiham; Ali, Khadeeja; Pina-amargos, Fabian; Angulo-valdes, Jorge A.; Asher, Jacob; Barcia, Laura Garcia; Beaufort, Oceane; Benjamin, Cecilie; Bernard, Anthony T. F.; Berumen, Michael L.; Bierwagen, Stacy; Bonnema, Erika; Bown, Rosalind M. K.; Bradley, Darcey; Brooks, Edd; Brown, J. Jed; Buddo, Dayne; Burke, Patrick; Caceres, Camila; Cardenosa, Diego; Carrier, Jeffrey C.; Caselle, Jennifer E.; Charloo, Venkatesh; Claverie, Thomas; Clua, Eric; Cochran, Jesse E. M.; Cook, Neil; Cramp, Jessica; D'Alberto, Brooke; De Graaf, Martin; Dornhege, Mareike; Estep, Andy; Fanovich, Lanya; Farabough, Naomi F.; Fernando, Daniel; Flam, Anna L.; Floros, Camilla; Fourqurean, Virginia; Garla, Ricardo; Gastrich, Kirk; George, Lachlan; Graham, Rory; Guttridge, Tristan; Hardenstine, Royale S.; Heck, Stephen; Henderson, Aaron C.; Hertler, Heidi; Hueter, Robert; Johnson, Mohini; Jupiter, Stacy; Kasana, Devanshi; Kessel, Steven T.; Kiilu, Benedict; Kirata, Taratu; Kuguru, Baraka; Kyne, Fabian; Langlois, Tim; Ledee, Elodie J. I.; Lindfield, Steve; Luna-acosta, Andrea; Maggs, Jade; Manjaji-matsumoto, B. Mabel; Marshall, Andrea; Matich, Philip; Mccombs, Erin; Mclean, Dianne; Meggs, Llewelyn; Moore, Stephen; Mukherji, Sushmita; Murray, Ryan; Kaimuddin, Muslimin; Newman, Stephen J.; Nogues, Josep; Obota, Clay; O'Shea, Owen; Osuka, Kennedy; Papastamatiou, Yannis P.; Perera, Nishan; Peterson, Bradley; Ponzo, Alessandro; Prasetyo, Andhika; Quamar, L. M. Sjamsul; Quinlan, Jessica; Ruiz-abierno, Alexei; Sala, Enric; Samoilys, Melita; Scharer-umpierre, Michelle; Schlaff, Audrey; Simpson, Nikola; Smith, Adam N. H.; Sparks, Lauren; Tanna, Akshay; Torres, Ruben; Travers, Marie-agnes; Van Zinnicq Bergmann, Maurits; Vigliola, Laurent; Ward, Juney; Watts, Alexandra M.; Wen, Colin; Whitman, Elizabeth; Wirsing, Aaron J.; Wothke, Aljoscha; Zarza-gonzalez, Esteban; Cinner, Joshua E.. |
Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status1,2. Yet much of what is known about sharks has been inferred from catch records in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats3. Here we address this knowledge gap using data from more than 15,000 standardized baited remote underwater video stations that were deployed on 371 reefs in 58 nations to estimate the conservation status of reef sharks globally. Our results reveal the profound impact that fishing has had on reef shark populations: we observed no sharks on almost 20% of the surveyed reefs. Reef sharks were almost completely absent from reefs in several nations, and... |
Tipo: Text |
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Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00644/75627/83233.pdf |
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Ben Cheikh, Yosra; Travers, Marie-agnes; Le Foll, Frank. |
The pathogenic strain V. splendidus 10/068 1T1 has previously been reported for its virulence to the blue mussel and for its capacity to alter immune responses. In this study, we expanded the knowledge on hemocyte-pathogen interactions by using in vitro and in vivo assays. V. splendidus 10/068 1T1 severely inhibited cell adhesion and acidic vacuole formation unlike the innocuous phylogenetically related V. splendidus 12/056 M24T1 which had no effect on these cell functions. Furthermore, the virulent bacteria decreased hemocyte viability (59% of viability after 24 h). Infection dynamics were explored by using a model based on water tank cohabitation with septic mussels infected by GFP-tagged V. splendidus 10/068 1T1. Experimental infections were... |
Tipo: Text |
Palavras-chave: Innate immunity; Bivalves; Vibrio; Infection; Experimental model; Hemocyte. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00400/51136/53772.pdf |
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Barbosa-solomieu, Valerie; Renault, Tristan; Travers, Marie-agnes. |
Massive mortality outbreaks in cultured bivalves have been reported worldwide and they have been associated with infection by a range of viral and bacterial pathogens. Due to their economic and social impact, these episodes constitute a particularly sensitive issue in Pacific oyster (Crassostrea gigas) production. Since 2008, mortality outbreaks affecting C. gigas have increased in terms of intensity and geographic distribution. Epidemiologic surveys have lead to the incrimination of pathogens, specifically OsHV-1 and bacteria of the Vibrio genus, in particular Vibrio aestuarianus. Pathogen diversity may partially account for the variability in the outcome of infections. Host factors (age, reproductive status…) including their genetic background that has... |
Tipo: Text |
Palavras-chave: Pacific oyster; Spat; OsHV-1; Vibrio aestuarianus; Mortality. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00274/38534/37051.pdf |
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Guesdon, Stephane; Travers, Marie-agnes; Hervio Heath, Dominique; Derrien, Annick; Genauzeau, Sylvie; Schmitt, Anne; Quintric, Laure; Leroi, Laura; Pepin, Jean-francois. |
Since the spring of 2014, the mussel farming of Charente-Maritime and Vendée (French Atlantic coast) has experienced an unprecedented crisis. Mass mortality events of blue mussel (M. edulis) have affected livestock areas, decimating up to 100% of production in some farming areas. Investigation for infectious agents in moribund mussels revealed presence of bacteria capable of inducing mortalities. In this context, the MORBLEU research project (DPMA-Ifremer agreement) was initiated to explore potentially aggravating factors, associated or correlated with mortality of mussels. The aim of the present study is to support the hypothesis that these mortality episodes can be linked to an evolution of microbial communities. Based on historical data from Ifremer... |
Tipo: Text |
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Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00415/52696/53566.pdf |
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Lupo, Coralie; Travers, Marie-agnes; Tourbiez, Delphine; Barthélémy, Clement; Beaunée, Gaël; Ezanno, Pauline. |
Vibrio aestuarianus is a bacterium related to mortality outbreaks in Pacific oysters, Crassostrea gigas, in France, Ireland, and Scotland since 2011. Knowledge about its transmission dynamics is still lacking, impairing guidance to prevent and control the related disease spread. Mathematical modeling is a relevant approach to better understand the determinants of a disease and predict its dynamics in imperfectly observed pathosystems. We developed here the first marine epidemiological model to estimate the key parameters of V. aestuarianus infection at a local scale in a small and closed oyster population under controlled laboratory conditions. Using a compartmental model accounting for free-living bacteria in seawater, we predicted the infection dynamics... |
Tipo: Text |
Palavras-chave: Marine epidemiology; Parameter estimation; Compartmental model; ABC method; Global sensitivity analysis; Basic reproduction number R-0; Crassostrea gigas; Oyster mortality. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00495/60652/64148.pdf |
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Pepin, Jean-francois; Benabdelmouna, Abdellah; Degremont, Lionel; Guesdon, Stephane; Le Moine, Olivier; Morga, Benjamin; Bierne, Nicolas; Travers, Marie-agnes; Robert, Stephane; Soletchnik, Patrick. |
Depuis 2014, des épisodes de mortalité anormale affectent les cheptels mytilicoles tant adultes que juvéniles. Dès l’année 2015, une première année d’étude a été réalisée au travers de l’action MORBLEU (Mortalité des moules Bleues). Elle a été menée dans les Pertuis charentais et la baie de Bourgneuf. Dans ce même contexte, elle a été reconduite en 2016 afin de poursuivre l’analyse des données collectées en 2015, renouveler une campagne d’étude et d’observation in situ, formuler des hypothèses autour de facteurs favorisants ces épisodes de mortalité de moules, développer des essais permettant de tester ces hypothèses dans le futur et produire des lots de moules pour ces essais et pour caractériser le potentiel adaptatif des animaux face aux épisodes de... |
Tipo: Text |
Palavras-chave: Moules; Mytilus edulis; Facteurs environnementaux; Mortalité; Equilibre microbien; Populations; Qualité cytogénétique; Anomalies hémocytaires; Expression de gènes; Physiologie. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00391/50288/50978.pdf |
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Pepin, Jean-francois; Benabdelmouna, Abdellah; Bierne, Nicolas; Costes, Louis; Degremont, Lionel; Garcia, Celine; Guesdon, Stephane; Lamy, Jean-baptiste; Le Moine, Olivier; Morga, Benjamin; Normand, Julien; Robert, Stephane; Saunier, Alice; Soletchnik, Patrick; Travers, Marie-agnes. |
Depuis 2014, des épisodes de mortalité anormale affectent les cheptels mytilicoles tant adultes que juvéniles. Dès l’année 2015, une étude spécifique cofinancée par la DPMA et réalisée par l’Ifremer a été initiée, l’action de recherche MORBLEU (Mortalité des moules Bleues). Les années 2015 et 2016 ont permis de dégager des éléments de connaissance et des pistes relatifs aux facteurs biotiques et abiotiques qui semblent intervenir dans le phénomène de hausse de mortalité des moules depuis 2014. Pour l’année 2017, les trois objectifs principaux étaient de : i) poursuivre la description du phénomène de mortalité ainsi que le contexte environnemental associé en effectuant une nouvelle campagne d’études et d’observations in situ, ii) tester des hypothèses... |
Tipo: Text |
Palavras-chave: Moules; Mytilus edulis; Mortalité; Statut cytogénétique; Anomalies génomiques; Populations; Facteurs environnementaux; Ecologie microbienne. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00503/61503/65337.pdf |
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Registros recuperados: 54 | |
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