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| Registros recuperados: 115 | |
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| Pouvreau, Stephane; Cochet, Hélène; Gachelin, Sonia; Chaudemanche, Samuel; Fabien, Aurélie. |
| L’huitre plate native des côtes européennes, est une espèce emblématique de Bretagne. Convoitée depuis l'Antiquité, sur-pêchée au 19ème siècle, fleuron de l'ostréiculture au 20ème, elle est désormais menacée de disparition à l'aube du 21ème. Sous l'impulsion de la commission OSPAR mais aussi dans un contexte grandissant de crise écologique et d'érosion de la biodiversité imposant une nécessaire conservation et/ou restauration de nos patrimoines naturels, une alliance européenne réunissant biologistes et gestionnaires a été créée en novembre 2017 à Berlin sous l'égide de l'Agence Allemande de Conservation de la Nature (BFN) avec un seul objectif : favoriser le retour de l'huitre plate sur les côtes. Cette alliance européenne pour la restauration de l'huitre... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00505/61629/65551.pdf |
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| Pouvreau, Stephane; Cochet, Hélène; Fabien, Aurélie; Arzul, Isabelle; Lapegue, Sylvie; Gachelin, Sonia; Salaun, Benoit. |
| L’huitre plate, la seule huitre native des côtes européennes, est une espèce emblématique de Bretagne. Convoitée depuis l'Antiquité, sur-pêchée au 19ème siècle, fleuron de l'ostréiculture au 20ème, elle est désormais menacée de disparition à l'aube du 21ème. Sous l'impulsion de la commission OSPAR mais aussi dans un contexte grandissant de crise écologique et d'érosion de la biodiversité imposant une nécessaire conservation et/ou restauration de nos patrimoines naturels, une alliance européenne réunissant biologistes et gestionnaires a été créée en novembre 2017 à Berlin sous l'égide de l'Agence Allemande de Conservation de la Nature (BFN) avec un objectif commun: favoriser le retour de l'huitre plate sur les côtes européennes. Cette alliance pour la... |
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| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00683/79506/82154.pdf |
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| Pouvreau, Stephane; Rambeau, Marc; Cochard, Jean-claude; Robert, Rene. |
| Classically, investigation of the internal morphology and composition of molluscs and especially bivalves relies on destructive method (biometry, biochemistry and histology). These techniques have given essential information, but in contrast are time consuming and lead to the irreversible loss of the animal while they don't allow integration of the various levels of molecular-to-organism functioning. The aim of this study is to analyze for the first time the potential of NMR (nuclear magnetic resonance) imaging (MRI) to depict, with sufficient resolution and satisfactory contrast, the anatomy of a bivalve model, the Pacific oyster, Crassostrea gigas, without opening it. MRI experiments were carried out at 19 °C in several non-anaesthetized adult Pacific... |
| Tipo: Text |
Palavras-chave: In vivo physiology; Aquaculture; Anatomy; MRI; Pacific oyster. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1819.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. |
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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... |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00627/73915/73251.pdf |
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| Pouvreau, Stephane; Morizur, Yvon. |
| This study provides some background on the set nets and the use of the gears. The various metiers using set nets are presented by region and maritime basin detailing the target species. The physical characteristics of nets (type, mesh), the number of vessels engaged in the activity, fishing areas, the amount of material used and the composition of the catch are inventoried by target species. Intraspecific selectivity for the main target species of set nets is examined in light of the available size composition of catches of turbot, brill, monkfish, pollack, red mullet, bass, common sole, rays, hake, spider crab, lobster. Few differences exist between the nets (single layer) and trammel nets except for the lobster. Minimum mesh sizes are suggested by target... |
| Tipo: Text |
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| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00049/16036/13511.pdf |
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| Morizur, Yvon; Pouvreau, Stephane; Guenole, Annie. |
| Observers were set on board of fishing vessels from North Brittanny ports during one full year (1992-93). This study granted by EC Commission (contract CE/DGXIV-C-1 n° 1992/06) was a first approach for assessing French discards in the western English Channel. It identifies the main species discarded and produces a rough estimate of discard rates and size compositions in each métier targeting fish. The major reasons for variability were explained. Size compositions of catches and discards were provided in order to permit better estimates of the mortality induced by fishing operations. The fixed nets observed were large mesh nets (270 to 360 mm) targeting monkfish and small mesh nets (<200 mm) targeting coastal resources. Netting was found to be more... |
| Tipo: Text |
Palavras-chave: France; Western English Channel; Bottom trawls; Fixed nets; Fisheries; Discards. |
| Ano: 1996 |
URL: https://archimer.ifremer.fr/doc/1996/rapport-1730.pdf |
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| Fleury, Elodie; Corporeau, Charlotte; Pouvreau, Stephane. |
| Occupant une place de premier ordre dans nos paysages côtiers, l’ostréiculture est le premier contributeur de la filière aquacole française avec une production estimée à 85 000 tonnes ces dernières années. Véritable espèce ingénieur, l’huître creuse joue aussi un rôle essentiel sur le plan écologique dans les écosystèmes qui l’abritent. Pourtant, depuis plusieurs années, l’ostréiculture subie une baisse de production et les bancs naturels, garants de la diversité génétique, sont mis en danger. Ces phénomènes sont la conséquence directe de l’épizootie causée par OsHV-1 µVar frappant les naissains et des mortalités d’adultes associées à la bactérie Vibrio aestuarianus. Ces épisodes de mortalités accrues ne sont pas nouveaux mais leur récurrence et leur... |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00433/54425/55774.pdf |
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| Le Moullac, Gilles; Queau, Isabelle; Le Souchu, Pierrick; Pouvreau, Stephane; Moal, Jeanne; Le Coz, Jean-rene; Samain, Jean-francois. |
| The purpose of this study was to examine the responses of the oyster C. gigas to oxygen levels at subcellular and whole-organism levels. Two experiments were carried out. The first experiment was designed to measure at 15°C, 20°C and 25°C for 20 hours the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of oxygen. The goal of this first part was to estimate the hypoxic threshold for oysters below which their metabolism shifts toward anaerobiosis, by estimating the oxygen critical point (PcO2) at 15, 20 and 25°C. The second experiment was carried out to evaluate the metabolic adaptations to hypoxia for 20 days at three temperatures: 12°C, 15°C and 20°C. The metabolic pathways were characterized by the... |
| Tipo: Text |
Palavras-chave: Succinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Temperature; Hypoxia; Oysters. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2693.pdf |
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| Gourault, Melaine; Petton, Sebastien; Thomas, Yoann; Pecquerie, Laure; Marques, Goncalo M.; Cassou, Christophe; Fleury, Elodie; Paulet, Yves-marie; Pouvreau, Stephane. |
| Identifying the drivers that control the reproductive success of a population is vital to forecasting the consequences of climate change in terms of distribution shift and population dynamics. In the present study, we aimed to improve our understanding of the environmental conditions that allowed the colonization of the Pacific oyster, Crassostrea gigas, in the Bay of Brest since its introduction in the 1960s. We also aimed to evaluate the potential consequences of future climate change on its reproductive success and further expansion. Three reproductive traits were defined to study the success of the reproduction: the spawning occurrence, synchronicity among individuals and individual fecundity. We simulated these traits by applying an individual-based... |
| Tipo: Text |
Palavras-chave: DEB model; IPCC scenarios; Reproductive traits; Crassostrea gigas; Bay of Brest. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00440/55188/56794.pdf |
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| Bourles, Yves; Maurer, Daniele; Le Moine, Olivier; Geairon, Philippe; Mazurie, Joseph; Gangnery, Aline; Alunno-bruscia, Marianne; Pouvreau, Stephane; Goulletquer, Philippe. |
| Oyster farming is the main aquaculture activity in France, where Pacific oyster (Crassostrea gigas) is spatially cultured from the English Channel to the Mediterranean coasts. Oyster growth performance monitored along French coasts are widely heterogeneous among culture sites and over years. Many studies have been carried out to understand the effects of environmental factors on oyster growth and physiology, by using bioenergetics growth models. However, most of these studies were site-specific. As an example, the model developed by Barillé et al. (1997), which was extensively specified with more than 50 parameters, was validated in the Marennes-Oléron Bay, but cannot be successfully applied to other culture sites without re-estimating parameters or... |
| Tipo: Text |
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| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00032/14367/11657.pdf |
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| Bourles, Yves; Alunno-bruscia, Marianne; Pouvreau, Stephane; Tollu, Guillaume; Leguay, Didier; Arnaud, Christophe; Goulletquer, Philippe; Kooijman, S. |
| A bio-energetic model, based on the DEB theory exists for the Pacific oyster Crassostrea gigas. Pouvreau et al. [Pouvreau, S., Bourles, Y., Lefebvre, S., Gangnery, A., Alunno-Bruscia, M., 2006. Application of a dynamic energy budget model to the Pacific oyster, C. gigas, reared under various environmental conditions. J. Sea Res. 56, 156167.] successfully applied this model to oysters reared in three environments with no tide and low turbidity, using chlorophyll a concentration as food quantifier. However, the robustness of the oyster-DEB model needs to be validated in varying environments where different food quantifiers reflect the food available for oysters, as is the case in estuaries and most coastal ecosystems. We therefore tested the oyster-DEB... |
| Tipo: Text |
Palavras-chave: Coastal Environment; Temperature effect; Food Quantifiers; Crassostrea gigas; Bivalves; Modelling; DEB theory. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6436.pdf |
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| Thomas, Yoann; Mazurie, Joseph; Alunno-bruscia, Marianne; Bacher, Cedric; Bouget, Jean-francois; Gohin, Francis; Pouvreau, Stephane; Struski, Caroline. |
| In order to assess the potential of various marine ecosystems for shellfish aquaculture and to evaluate their carrying capacities, there is a need to clarify the response of exploited species to environmental variations using robust ecophysiological models and available environmental data. For a large range of applications and comparison purposes, a non-specific approach based on ‘generic’ individual growth models offers many advantages. In this context, we simulated the response of blue mussel (Mytilus edulis L.) to the spatio-temporal fluctuations of the environment in Mont Saint-Michel Bay (North Brittany) by forcing a generic growth model based on Dynamic Energy Budgets with satellite-derived environmental data (i.e. temperature and food). After a... |
| Tipo: Text |
Palavras-chave: Mussel; DEB; SeaWifs; Aquaculture; Site Selection; Resource Management. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00037/14836/14537.pdf |
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| Grangere, Karine; Menesguen, Alain; Lefebvre, Sébastien; Bacher, Cedric; Pouvreau, Stephane. |
| It is well known that temporal changes in bivalve body mass are strongly correlated with temporal variations in water temperature and food supply. In order to study the influence of the year-to-year variability of environmental factors on oyster growth, we coupled a biogeochemical sub-model, which simulates trophic resources of oysters (i.e. phytoplankton biomass via chlorophyll a), and an ecophysiological sub-model, which simulates growth and reproduction (i.e. gametogenesis and spawning), using mechanistic bases. The biogeochemical sub-model successfully simulated phytoplankton dynamics using river nutrient inputs and meteorological factors as forcing functions. Adequate simulation of oyster growth dynamics requires a relevant food quantifier compatible... |
| Tipo: Text |
Palavras-chave: Baie des Veys; Normandy; France; Physiological Status; Phytoplankton Carbon Concentration; Food Supply; Temperature; Dynamic Energy Budget model; Biogeochemical Model. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6809.pdf |
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| Bacca, Helene; Huvet, Arnaud; Fabioux, Caroline; Daniel, Jean-yves; Delaporte, Maryse; Pouvreau, Stephane; Van Wormhoudt, A; Moal, Jeanne. |
| To investigate the control at the mRNA level of glycogen metabolism in the cupped oyster Crassostrea gigas, we report in the present paper the cloning and characterization of glycogen phosphorylase and synthase cDNAs (Cg-GPH and Cg-GYS, respectively, transcripts of main enzymes for glycogen use and storage), and their first expression profiles depending on oyster tissues and seasons. A strong expression of both genes was observed in the labial palps and the gonad in accordance with specific cells located in both tissues and ability to store glucose. Cg-GPH expression was also found mainly in muscle suggesting ability to use glycogen as readily available glucose to. supply its activity. For seasonal examinations, expression of Cg-GYS and Cg-GPH genes... |
| Tipo: Text |
Palavras-chave: Reproduction; Regulation; Oyster; Glycogen; Expression; Gene; Energy; Crassostrea gigas; Bivalve. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-435.pdf |
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| Charria, Guillaume; Schmitt, François; Artigas, Felipe; Berthebaud, Eric; Bonnat, Armel; Bourrin, François; Bozec, Yann; Cariou, Thierry; Claquin, Pascal; Conan, Pascal; Coppola, Laurent; Delalée, Franck; Facq, Jean-valery; Farcy, Patrick; Ferreira, Sophie; Garcia, Fabrice; Grisoni, Jean-michel; Jacqueline, Franck; Jacquet, Matthias; Lefebvre, Alain; Leredde, Yann; Le Roux, Jean-francois; Mas, Sébastien; Mostajir, Behzad; Mousseau, Laure; Pairaud, Ivane; Petton, Sebastien; Pouvreau, Stephane; Quemener, Loic; Ravel, Christophe; Raimbault, Patrick; Repecaud, Michel; Retho, Michael; Rimmelin-maury, Peggy; Riou, Philippe; Savoye, Nicolas; Souchu, Philippe; Verney, Romaric; Vuillemin, Renaud. |
| COAST-HF (Coastal OceAn observing SysTem – High Frequency) is a French national observation network of the physical and biogeochemical dynamics of the coastal ocean, at high frequency. COAST-HF aims at understanding and analysing changes of contrasted coastal ecosystems at different temporal scales from extreme or intermittent high frequency (hour, day) events to multi-year trends. Since several years (from 2000 for the longest time series in Bay of Brest), the network extends along the English Channel, Atlantic and Mediterranean French coasts through 14 fixed platforms instrumented for the in situ high-frequency (≤ 1h) observations. Several French research institutes (IFREMER, CNRS, Marine Universities) are operating these systems. The organization of... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00635/74723/74708.pdf |
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| Gourault, Melaine; Lavaud, Romain; Leynaert, Aude; Pecquerie, Laure; Paulet, Yves-marie; Pouvreau, Stephane. |
| The present study aimed to improve understanding of the environmental conditions influencing the reproductive cycle of the great scallop Pecten maximus in two locations in Brittany (France). We also evaluated potential consequences of future climate change for reproductive success in each site. We simulated reproductive traits (spawning occurrences and synchronicity among individuals) of P. maximus, using an existing Dynamic Energy Budget (DEB) model. To validate and test the model, we used biological and environmental datasets available for the Bay of Brest (West Brittany, France) between 1998 and 2003. We also applied the scallop DEB model in the Bay of Saint-Brieuc (North Brittany, France) for the same period (1998–2003) to compare the reproductive... |
| Tipo: Text |
Palavras-chave: Pecten maximus; DEB theory; Reproduction cycle; IPCC scenarios; Bay of Brest; Bay of Saint-Brieuc. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00458/57012/58910.pdf |
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| Davenel, Armel; Pouvreau, Stephane; Cambert, Mireille; Suquet, Marc; Mariette, Francois. |
| MR imaging is the most appropriate non-invasive technique for quantifying the growth of somatic and gonad tissues and to determine sex in the Pacific oyster, Crassostrea gigas. However, this technique is too costly for field studies where oysters are used as bioindicators of environmental quality or to be applied routinely in hatcheries. We have tested the ability of low Nuclear Magnetic Resonance relaxometry, a much less expensive technique, to obtain phenotype parameters that can be used to monitor the physiological state of oysters. NMR measurements were carried out at three different periods using a low field spectrometer equipped with a 50 mm diameter probe to investigate 60 oysters in their first year of maturity, which were then dissected to measure... |
| Tipo: Text |
Palavras-chave: Sex identification; Growth; NMR; Crassostrea gigas; Phenotype characterization. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6456.pdf |
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| Davenel, Armel; Quellec, Stéphane; Pouvreau, Stephane. |
| The aim of this study was to test the ability of magnetic resonance imaging (MRI) technique to characterize gonad development and to determine the sex of live Pacific oysters through their shells. A preliminary nuclear magnetic resonance (NMR) retaxometry study was conducted to characterize T-1 and T-2 NMR relaxation parameters for the main oyster organs. This showed that T-1-weighted MRI sequences were most appropriate to optimize contrasts between tissues in images. The results showed that gray levels of gonads in images acquired with gradient-echo sequence were variably affected by T-2* weighting effect. However, the ovaries systematically gave a hypersignal in spin-echo T-1-weighted images, and stack histograms of female oysters showed a peak well... |
| Tipo: Text |
Palavras-chave: Spin echo; Gradient echo; Sex determination; Gonad maturation; Oyster. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1987.pdf |
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| Registros recuperados: 115 | |
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