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| Registros recuperados: 76 | |
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| Genard, Bertrand; Moraga, Dario; Pernet, Fabrice; David, Elise; Boudry, Pierre; Tremblay, Rejean. |
| Quantification of mRNA of genes related to metabolism, immunity and cellular stress was examined in relation to a massive mortality event during the culture of American oyster larvae, Crassostrea virginica which was probably, in regard to previous microbiological analysis, induced by vibrio infection. To document molecular changes associated with the mortality event, mRNA levels were compared to biochemical and physiological data, previously described in a companion paper. Among the 18 genes studied, comparatively to the antibiotic control, 10 showed a lower relative gene expression when the massive mortality occurred. Six of them are presumed to be related to metabolism, corroborating the metabolic depression associated with the mortality event suggested... |
| Tipo: Text |
Palavras-chave: Massive mortality; Relative gene expression; Metabolism; Immunity; Cellular stress; Larvae. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00075/18585/16138.pdf |
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| Pernet, Fabrice; Lagarde, Franck; Cesmat, Ludovic; Jeannée, Nicolas; Barret, Jean; Le Gall, Patrik; Quere, Claudie; Fiandrino, Annie; Miguet, Marine; Boulet, Hélène; Keck, Nicolas; Roque D'Orbcastel, Emmanuelle. |
| Cette étude avait pour objectif principal de déterminer les facteurs explicatifs de la dynamique spatio-temporelle des surmortalités d’huîtres creuses dans la lagune de Thau. Les facteurs étudiés étaient : la pathologie (détection d’ADN appartenant à l’Ostreid herpesvirus 1 OsHV-1 et au groupe bactérien Vibrio splendidus), l’état énergétique des huîtres (triglycérides, sucres totaux et acides gras comme marqueurs trophiques), les pratiques d’élevage et l’hydrodynamique. Afin de répondre à ces objectifs, nous avons suivi la mortalité d’un lot d’huîtres sentinelles, âgé de moins d’un an, maintenu indemne de mortalité, dans lequel on ne détectait pas d’ADN appartenant à OsHV-1. Le lot a été déployé mi-mars 2011 sur 106 stations dans la lagune de Thau, où les... |
| Tipo: Text |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00092/20355/18015.pdf |
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| Petton, Bruno; Boudry, Pierre; Alunno-bruscia, Marianne; Pernet, Fabrice. |
| Mortalities of oyster Crassostrea gigas seed associated with ostreid herpesvirus OsHV-1 μVar have been observed in many oyster-producing countries since 2008. The present study, comprised of 4 complementary experiments, aimed to identify factors associated with disease-induced oyster mortality in order to propose mitigation strategies. Our first experiment compared survival of oysters from natural spatfall with others sampled from nurseries, after thermal elevation in the laboratory from <14 to 21°C. A total of 60% of the tested wild seed batches (n = 51) were infected by OsHV-1, exhibited mortality and were able to transmit the disease to cohabited naïve oysters. Comparatively, only 1 out of the 32 tested batches sampled from nurseries presented... |
| Tipo: Text |
Palavras-chave: Epidemiology; Risk analyses; Shellfish farming; Virus OsHV-1 mu Var. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00257/36777/35390.pdf |
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| Pernet, Fabrice; Gachelin, Sonia; Stanisière, Jean-yves; Petton, Bruno; Fleury, Elodie; Mazurié, Joseph. |
| The intertidal zone is characterized by a sharp vertical gradient of environmental stress, which structures species distribution and their interactions. Few studies, however, have examined the influence of tidal height on host–pathogen interactions. Here, we investigated how the tidal height influence outbreak of the Ostreid herpesvirus type 1 (OsHV-1) affecting the Pacific oyster. A volunteer network composed of 20 oyster growers monitored the survival of 28 batches of oysters during an epizootic event in Southern Brittany, France. Oysters were spat from wild collection or hatchery production. The sampling sites were spread over a 150-km2 area with a tidal height ranging from 0.98 to 2.90 m. Concomitantly, we followed survival of oyster spats in relation... |
| Tipo: Text |
Palavras-chave: Aquaculture; Citizen science; Marine epidemiology and health; OsHV-1; Risk analysis. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00491/60271/63981.pdf |
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| Delisle, Lizenn; Pauletto, Marianna; Vidal-dupiol, Jeremie; Petton, Bruno; Bargelloni, Luca; Montagnani, Caroline; Pernet, Fabrice; Corporeau, Charlotte; Fleury, Elodie. |
| Of all environmental factors, seawater temperature plays a decisive role in triggering marine diseases. Like fever in vertebrates, high seawater temperature could modulate the host response to pathogens in ectothermic animals. In France, massive mortality of Pacific oysters, Crassostrea gigas, caused by the ostreid herpesvirus 1 (OsHV-1) is markedly reduced when temperatures exceed 24°C in the field. In the present study we assess how high temperature influences the host response to the pathogen by comparing transcriptomes (RNA sequencing) during the course of experimental infection at 21°C (reference) and 29°C. We show that high temperature induced host physiological processes that are unfavorable to the viral infection. Temperature influenced the... |
| Tipo: Text |
Palavras-chave: Anti-viral molecular pathway; Host-pathogen interaction; Marine disease; OsHV-1; Resistance; Temperature. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00656/76806/77974.pdf |
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| Le Bris, Cedric; Richard, Gaelle; Paillard, Christine; Lambert, Christophe; Seguineau, Catherine; Gauthier, Olivier; Pernet, Fabrice; Guerard, Fabienne. |
| Manila clams, Venerupis philippinarum (Adams and Reeve, 1850), were experimentally challenged with two Vibrio tapetis strains: CECT4600T, the causative agent of Brown Ring Disease (BRD); and LP2 supposedly non-pathogenic in V. philippinarum. Changes in phenoloxidase (PO) and superoxide dismutase (SOD), two major enzymes involved in immunity, were studied in two tissues, the mantle and hemolymph for 30 days after infection in the extrapallial cavity. Bacterial infection in V. philippinarum resulted in modulation of PO and SOD activities that was both tissue- and time-dependent. A response at early times was detected in the mantle and was associated with significant increases in PO and SOD activities in LP2- and CECT4600T-challenged clams 36h post injection.... |
| Tipo: Text |
Palavras-chave: Venerupis philippinarum; Vibrio tapetis; Immunity; Phenoloxidase; Superoxide dismutase. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00221/33257/31733.pdf |
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| Seychelles, Laurent H.; Doiron, Kim; Audet, Celine; Tremblay, Rejean; Pernet, Fabrice; Lemarchand, Karine. |
| Rotifers (Brachionus plicatilis), commonly used at first feeding in commercial fish hatcheries, carry a large bacteria load. Because they are relatively poor in essential fatty acids, it is common practice to enrich them with fatty acids, including arachidonic acid (AA). This study aims to determine whether prey enrichment with AA may act as a prebiotic and modify the microbial community composition either in AA-enriched rotifer cultures or in larval-rearing water using winter flounder (Pseudopleuronectes americanus) as a larval fish model. AA enrichment modified the bacterial community composition in both the rotifer culture tanks and the larval-rearing tanks. We observed an increase in the number of cultivable bacteria on TCBS (thiosulfate-citrate-bile... |
| Tipo: Text |
Palavras-chave: Communauté bactérienne; Rotifères; Enrichissement en acide arachidonique; Vibrio sp.; Prébiotique; Bacterial community; Rotifers; Arachidonic acid enrichment; Vibrio sp.; Prebiotic. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00137/24778/25189.pdf |
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| De Lorgeril, Julien; Escoubas, Jean Michel; Loubiere, Vincent; Pernet, Fabrice; Le Gall, Patrik; Vergnes, Agnes; Aujoulat, Fabien; Jeannot, Jean-luc; Jumas-bilak, Estelle; Got, Patrice; Gueguen, Yannick; Destoumieux-garzon, Delphine; Bachere, Evelyne. |
| Since 2008, juvenile Crassostrea gigas oysters have suffered from massive mortalities in European farming areas. This disease of complex etiology is still incompletely understood. Triggered by an elevated seawater temperature, it has been associated to infections by a herpes virus named OsHV-1 as well as pathogenic vibrios of the Splendidus clade. Ruling out the complexity of the disease, most of our current knowledge has been acquired in controlled experiments. Among the many unsolved questions, it is still ignored what role immunity plays in the capacity oysters have to survive an infectious episode. Here we show that juvenile oysters susceptible to the disease mount an inefficient immune response associated with microbial permissiveness and death. We... |
| Tipo: Text |
Palavras-chave: Host pathogen interaction; Innate immunity; Invertebrate; Mollusk; In situ mortality; Total bacteria; Crassostrea gigas. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00433/54470/55845.pdf |
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| Pernet, Fabrice; Lupo, Coralie; Bacher, Cedric; Whittington, Richard J.. |
| Emerging diseases pose a recurrent threat to bivalve aquaculture. Recently, massive mortality events in the Pacific oyster Crassostrea gigas associated with the detection of a microvariant of the ostreid herpesvirus 1 (OsHV-1 µVar) have been reported in Europe, Australia and New Zealand. Although the spread of disease is often viewed as a governance failure, we suggest that the development of protective measures for bivalve farming is presently held back by the lack of key scientific knowledge. In this paper, we explore the case for an integrated approach to study the management of bivalve disease, using OsHV-1 as a case study. Reconsidering the key issues by incorporating multidisciplinary science could provide a holistic under-standing of OsHV-1 and... |
| Tipo: Text |
Palavras-chave: Bivalve; Disease management; Epidemiology; Multidisciplinary; Risk. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00314/42537/41912.pdf |
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| Pernet, Fabrice; Tamayo, David; Petton, Bruno. |
| Mortalities of oyster seed of Crassostrea gigas associated with ostreid herpes virus OsHV-1 μVar have been observed in many oyster producing countries since 2008. The objective of this study was to further investigate whether low temperature treatments can offer a viable option to mitigate oyster mortalities. An experiment was set-up to further evaluate the effect of low temperature treatments (10 and 13°C vs. 21°C) and their duration (6 d to 83 d) on the survival of oysters previously infected with OsHV-1 μVar by means of exposure to field conditions in areas where mortalities were occurring. Average survival of oysters infected with OsHV-1μVar was 71% after 83 d at low temperatures compared to only 23% in controls maintained at 21°C. During... |
| Tipo: Text |
Palavras-chave: Bivalve; Disease; OsHV-1; Oyster; Temperature; Virus. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00259/37047/35555.pdf |
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| Petton, Bruno; Pernet, Fabrice; Robert, Rene; Boudry, Pierre; Alunno-bruscia, Marianne. |
| Since 2008, mass mortalities of 1-yr-old oysters Crassostrea gigas associated with ostreid herpes virus OsHV-1 μVar have occurred along all coasts of France. These mortality events represent the most serious crisis for the French oyster industry since the introduction of C. gigas in the early 1970s. Temperature is commonly one of the major triggering factors of disease epizootics, notably for aquatic species. In France, OsHV-1 is generally detected in dying oysters when seawater temperature is higher than 16° C. The influence of temperature on OsHV-1 detection and expression was also demonstrated for C. gigas larvae and suspected for juveniles. The present study aims to characterize the effect of temperature on disease transmission and survival related... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00151/26259/24343.pdf |
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| Genard, Bertrand; Miner, Philippe; Nicolas, Jean-louis; Moraga, Dario; Boudry, Pierre; Pernet, Fabrice; Tremblay, Rejean. |
| Background: Bacterial infections are common in bivalve larvae and can lead to significant mortality, notably in hatcheries. Numerous studies have identified the pathogenic bacteria involved in such mortalities, but physiological changes associated with pathogen exposure at larval stage are still poorly understood. In the present study, we used an integrative approach including physiological, enzymatic, biochemical, and molecular analyses to investigate changes in energy metabolism, lipid remodelling, cellular stress, and immune status of Crassostrea gigas larvae subjected to experimental infection with the pathogenic bacteria Vibrio coralliilyticus. Findings: Our results showed that V. coralliilyticus exposure induced (1) limited but significant increase... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00144/25504/23662.pdf |
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| Chouvelon, Tiphaine; Schaal, G.; Grall, J.; Pernet, Fabrice; Perdriau, M.; A-pernet, E. J.; Le Bris, H.. |
| Anthropogenic activities and land-based inputs into the sea may influence the trophic structure and functioning of coastal and continental shelf ecosystems, despite the numerous opportunities and services the latter offer to humans and wildlife. In addition, hydrological structures and physical dynamics potentially influence the sources of organic matter (e.g., terrestrial versus marine, or fresh material versus detrital material) entering marine food webs. Understanding the significance of the processes that influence marine food webs and ecosystems (e.g., terrestrial inputs, physical dynamics) is crucially important because trophic dynamics are a vital part of ecosystem integrity. This can be achieved by identifying organic matter sources that enter food... |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00275/38612/37468.pdf |
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| Lagarde, Franck; Roque D'Orbcastel, Emmanuelle; Perignon, Adeline; Mortreux, Serge; Fuhrmann, Marine; Le Gall, Patrik; Leurion, Axel; Chiantella, Claude; Bec, Beatrice; Roques, Cecile; Bonnet, Delphine; Cochet, Helene; Boj, Marie; Gervasoni, Erika; Miron, Gilles; Fiandrino, Annie; Pouvreau, Stephane; Pernet, Fabrice. |
| We bring new items in connection with the origins of the natural recruitment variability of the Pacific oyster Crassostrea gigas in Thau lagoon. A poor relationship between " number of larvae" and "number of spat" in 2012 shows a biological lock around oysterculture areas during the metamorphosis in spite of better success of recruitment outside shellfish farming zone. A comprehensive analysis of environmental factors effects and the development of prognosis tools are planned to assist oysterfarmers in rationalization of natural oyster recruitment around Mediterranean lagoon. |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00165/27653/25822.pdf |
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| Fleury, Elodie; Barbier, Pierrick; Petton, Bruno; Normand, Julien; Thomas, Yoann; Pouvreau, Stephane; Daigle, Gaétan; Pernet, Fabrice. |
| Diseases pose an ongoing threat to aquaculture, fisheries and conservation of marine species, and determination of risk factors of disease is crucial for management. Our objective was to decipher the effects of host, pathogen and environmental factors on disease-induced mortality of Pacific oysters (Crassostrea gigas) across a latitudinal gradient. We deployed young and adult oysters at 13 sites in France and we monitored survival, pathogens and environmental parameters. The young oysters came from either the wild collection or the hatchery while the adults were from the wild only. We then used Cox regression models to investigate the effect of latitude, site, environmental factors and origin on mortality risk and to extrapolate this mortality risk to the... |
| Tipo: Text |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00627/73915/73251.pdf |
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| Soletchnik, Patrick; Mazurie, Joseph; Allain, Gwenhael; Bedier, Edouard; Benabdelmouna, Abdellah; Blin, Jean-louis; Bouquet, Anne-lise; Cochet, Hélène; Degremont, Lionel; Gaussem, Florian; Gervasoni, Erika; Glize, Philippe; Petton, Bruno; Roussel, Pierre-yves; Pernet, Fabrice. |
| This paper summarizes knowledge about relations between husbandry practices and oyster spat mortalities since 2008 in France. These relations are strictly analyzed from a panel of experiments set on the shore (in outdoor experiments) by Ifremer teams and technical institutes all over French coasts. Results show some practices are able to reduce spat mortality with some influencing factors relevant of spat quality (sanitary status, natural or genetic selection) or husbandry practices. Spat “free” of virus is able to survive up to 90% when it is isolated and confined in ponds or nursery, during an epidemic crisis. When outbreaks occurred in oyster beds, natural or nursery spat died in almost same proportions. In 2010, some studies conducted in Mediterranean... |
| Tipo: Text |
Palavras-chave: Surmortalité; Naissain; Huître creuse; OsHV-1; Pratiques culturales; Mortality; Spat; Cupped oyster; Crassostrea gigas; OsHV-1; Cultural practices. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00032/14280/25847.pdf |
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| Cochennec-laureau, Nathalie; Baud, Jean-pierre; Pepin, Jean-francois; Benabdelmouna, Abdellah; Soletchnik, Patrick; Lupo, Coralie; Garcia, Celine; Arzul, Isabelle; Boudry, Pierre; Huvet, Arnaud; Pernet, Fabrice; Bachere, Evelyne; Bedier, Edouard; Petton, Bruno; Gaussem, Florian; Stanisiere, Jean-yves; Degremont, Lionel. |
| Depuis 2008, la filière ostréicole française doit faire face à des surmortalités exceptionnelles des naissains d’huîtres creuses, Crassostrea gigas, (huîtres de moins d’un an) comprises entre 60 et 90% dans tous les sites d’élevage. Des cas de mortalité similaires ont été décrits en Irlande, dans les îles anglo-normandes, au Portugal en 2009 et au Royaume-Uni en 2010. Récemment deux épisodes de mortalité, associés à la présence d’un virus OsHV1 μvar (ou un variant très proche) ont été également décrits en Nouvelle Zélande (décembre 2010) et en Australie (janvier 2011) soulignant la vulnérabilité de la filière ostréicole dans le monde. L’objectif de ce document est de faire un point sur les recherches menées depuis l’apparition de ce phénomène et de... |
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| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00033/14423/11719.pdf |
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| Theriault, I; Pernet, Fabrice. |
| This study examines the effects of varying dietary lipids on growth, survival, lipid composition and behaviour in lobster Homarus americanus (Milne Edwards, 1837) postlarvae. Lobsters were fed one of 3 diets during their early ontogeny: (1) Artemac, a widely used Artemia replacement; (2) a ternary mixture consisting of Artemac, frozen Artemia adults and Artemia flakes; or (3) a mixture of live A. salina nauplii and adults. We evaluated the olfactory capacity (response to predator odour plume) and cryptic behaviour (ability to hide during settlement) of lobster postlarvae as a function of these diets and the lipid and the fatty acid composition of lobsters. Growth and survival of lobster postlarvae were highest in those fed live Artemia, followed by the... |
| Tipo: Text |
Palavras-chave: Settlement behaviour; Nutrition; Lipid; Habitat selection; Fatty acid; Crustacean larvae. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-4651.pdf |
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| Muir, Anna; Nunes, Flavia; Dubois, Stanislas; Pernet, Fabrice. |
| Acclimation and adaptation, which are key to species survival in a changing climate, can be observed in terms of membrane lipid composition. Remodelling membrane lipids, via homeoviscous adaptation (HVA), counteracts membrane dysfunction due to temperature in poikilotherms. In order to assess the potential for acclimation and adaptation in the honeycomb worm, Sabellaria alveolata, a reef-building polychaete that supports high biodiversity, we carried out common-garden experiments using individuals from along its latitudinal range. Individuals were exposed to a stepwise temperature increase from 15 °C to 25 °C and membrane lipid composition assessed. Our results suggest that S. alveolata was able to acclimate to higher temperatures, as observed by a... |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00354/46551/46361.pdf |
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| Registros recuperados: 76 | |
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