Consulta: creatorFacets:"Pouvreau, Stephane"
Registros recuperados: 115
Data/hora: 11/06/2024 01:24:58

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2011
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bernard, Ismael; Le Souchu, Pierrick; Queau, Isabelle; Talarmain, Eric; Auby, Isabelle; Maurer, Daniele; Barbier, Claire; Tournaire, Marie-pierre; D'Amico, Florence; Rumebe, Myriam; Neaud-masson, Nadine; Bedier, Edouard; Fleury, Elodie; Martin, Anne-genevieve; Claude, Serge; Langlade, Aime; Bouget, Jean-francois; Collin, Karine; Fortune, Mireille; Hitier, Benoist; Robert, Stephane; Guilpain, Patrice; Grizon, James; Seugnet, Jean-luc; Guesdon, Stephane; Quemener, Loic; Repecaud, Michel; Barbot, Stephane; Guillemot, Anne; Nonnotte, Lidwine; Duros, Wenceslas; Bonnat, Armel; Tarot, Stephane; Mille, Dominique; Geay, Amelie; Bouquet, Anne-lise.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage. Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple les années 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (les années 2003, 2006, 2008). A Marennes-Oléron, cette variabilité existe, même si elle est...
Tipo: Text
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00135/24649/22682.pdf

Temporal variability in the Pacific oyster spatfall along the French Coast: a new monitoring project
Provedor de dados: 5
Autores: Pouvreau, Stephane; Maurer, Daniele; Auby, Isabelle; Soletchnik, Patrick; Mille, Dominique; Bernard, Ismael; Bedier, Edouard.
In France, spatfall of Pacific Oysters occurs traditionally in two shellfish area of the south west of France: the Marennes-Oléron bay and the Arcachon basin. The spat collected in both sites ensures approx. 70 % of the need of the French oysters production (the other part is produced in hatcheries). But, since ten years, recruitment have become highly variable especially in Arcachon basin. For instance, in this site, spatfall (assessed at the end of the reproductive season) can vary between 50 oysters per collector to more than 20 000 oysters per collector (Figure 1). This huge variation arise questions from oysters producers and the French National Committee for Shellfish Culture want to get some explanations of the phenomenon. It is well known that...
Tipo: Text
Palavras-chave: Larvae; Reproduction; Recruitment; Spatfall; Crassostrea gigas.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/acte-4543.pdf

Modelling Crassostrea gigas growth and reproduction in different contrasted ecosystems by using dynamic energy budgets : generic validation of the oyster-DEB model
Provedor de dados: 5
Autores: 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
Ano: 2009
URL: http://archimer.ifremer.fr/doc/00032/14367/11657.pdf

Impact des facteurs environnementaux et des pratiques conchylicoles sur la baie du Mont Saint-Michel et la production conchylicole. Etude de scenarii par modélisation. Programme Liteau 3. Rapport Final
Provedor de dados: 5
Autores: Cugier, Philippe; Frangoudes, Katia; Blanchard, Michel; Mongruel, Remi; Perez, Jose; Le Mao, Patrick; Robin, T.; Fontenelle, Guy; Mazurie, Joseph; Cayocca, Florence; Pouvreau, Stephane; Olivier, F.
Tipo: Text
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00026/13707/10862.pdf

In situ distribution and characterization of the organic content of the oyster shell Crassostrea gigas (Mollusca, Bivalvia)
Provedor de dados: 5
Autores: Dauphin, Yannicke; Ball, Alexander D.; Castillo-michel, Hiram; Chevallard, Corinne; Cuif, Jean-pierre; Farre, Bastien; Pouvreau, Stephane; Salome, Murielle.
Cultivation of commercial oysters is now facing the possible influence of global change in sea water composition, commonly referred to as "ocean acidification". In order to test the potential consequence of the predicted environmental changes, a cultivation experiment was carried out. The left and right valves of the oyster shell Crassostrea gigas differ in their structure; moreover, lenses of non compact layers are irregular. The shell layers of juvenile C. gigas are studied using a variety of highly spatially resolved techniques to establish their composition and structure. Our results confirm the presence of three different calcitic structural types. The role of the lenses of chalky layers is not yet deciplered. Despite a common mineralogy, the...
Tipo: Text
Palavras-chave: Biomineral; Mollusc shell; Infrared spectroscopy; Laser confocal Microscope; Micro-XANES.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00118/22890/20797.pdf

Estimation, Préservation, Reconstitution des bancs sauvages d’huîtres plates en Baie de Quiberon
Provedor de dados: 5
Autores: Cochet, Hélène; Pouvreau, Stephane; Tanguy, Ludovic; Kerisit, Christophe.
L’huître plate, Ostrea edulis, est l’huître native des côtes européennes. Espèce emblématique de Bretagne, elle a subi deux épizooties successives dans les années 70 qui ont fait chuter sa production de 20 000 tonnes à moins de 2000 tonnes actuellement et disparaître de nombreux bancs naturels. Désormais l’espèce ne se reproduit plus que dans quelques baies et rias situées principalement en Bretagne et Normandie et le captage ne se pratique qu’en Baie de Quiberon et en Rade de Brest. Mais ce dernier est très variable d’une année à l’autre et a été particulièrement faible en Baie de Quiberon depuis 2010. De récentes études ont conclu que la diminution des stocks d’huîtres, notamment des bancs naturels de l’Ouest de la baie, pouvait être l’une des raisons à...
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00304/41488/40700.pdf

Ecophysiologie de la reproduction chez l'huître creuse, Crassostrea gigas
Provedor de dados: 5
Autores: Pouvreau, Stephane; Lepennec, M.
The reproductive cycle of Megathura crenulata was documented and quantification of oocyte lipid reserves with lipo-specific stains was explored in both this species and in Crassostrea gigas. The necessity of providing food to female broodstock C. gigas in spring was re-evaluated, because subsequent larval and post-larval rearing performance was not affected by broodstock starvation during conditioning. Developmental study of the organs responsible of particle processing in C. gigas allowed the identification of critical stages related to the ontogenesis of each organ, as well as a better understanding of the evolution of these organs, highly-modified in the Ostreidae. Ciliary type identification and mucocyte mapping from post-larval to adult stage showed...
Tipo: Text
Palavras-chave: Mucocytes; Mantle; Gill; Larvae postlarvae juveniles; Feeding; Crassostrea gigas; Megathura crenulata; Development; Reproduction; Mucocytes; Manteau; Branchie; Larves post larves juvéniles; Alimentation; Crassostrea gigas; Megathura crenulata; Développement; Reproduction.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/rapport-1867.pdf

Avis sur projet de création de lotissements de captage d'huîtres creuses sur la côte sud de la rade de Brest
Provedor de dados: 5
Autores: Le Bec, Claude; Boulben, Sylviane; Pouvreau, Stephane.
Tipo: Text
Ano: 2013
URL: https://archimer.ifremer.fr/doc/00131/24181/79417.pdf

Influence of food density and temperature on ingestion, growth and settlement of Pacific oyster larvae, Crassostrea gigas
Provedor de dados: 5
Autores: Rico Villa, Benjamin; Pouvreau, Stephane; Robert, Rene.
Ingestion, growth and metamorphosis of Pacific oyster, Crassostrea gigas, larvae were studied under controlled conditions of food density and temperature using a combination of a flow-through rearing system and a hydrobiological monitoring device. In a first experiment larvae were exposed to three different phytoplankton densities (12, 20 and 40 cells &amp;#956;l-1) while in a second trial larvae were reared at five different temperatures (17, 22, 25, 27 and 32°C). Both food concentration and temperature significantly affected the larval physiology throughout the entire development from D-veliger to young spat. Larvae survived over a wide range of both environmental parameters with high survival at the end of experiments. The feeding functional response...
Tipo: Text
Palavras-chave: Temperature; Food; Growth; Ecophysiology; Bivalve larvae; Crassostrea gigas.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2008/publication-4747.pdf

A single bio-energetics growth and reproduction model for the oyster Crassostrea gigas in six Atlantic ecosystems
Provedor de dados: 5
Autores: Alunno-bruscia, Marianne; Bourles, Yves; Maurer, Daniele; Robert, Stephane; Mazurie, Joseph; Gangnery, Aline; Goulletquer, Philippe; Pouvreau, Stephane.
Many studies based on bioenergetics growth models have investigated the effects of environmental factors on oyster (Crassostrea gigas) growth and physiology. However, most of these models are site-specific and cannot be applied to other culture sites without the re-estimation of parameters or re-formulation of some processes. We aimed to develop a generic growth model suitable for application in contrasting environments, with a constant set of parameters. We tested the oyster-DEB model (Bourlès et al. 2009) for the stimulation of C. gigas growth in different cohorts (spats and adults) at major shellfish culture sites in France, in several years: Arcachon (1993–1994); Marennes-Oléron (2007); Quiberon (1999, 2000, 2001); Rade de Brest (2008); Baie du...
Tipo: Text
Palavras-chave: DEB theory; Modelling; Bivalves; Crassostrea gigas; Phytoplankton; Temperature effect; Coastal environment.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00043/15403/12762.pdf

Intensive use of Lagrangian trajectories to quantify coastal area dispersion
Provedor de dados: 5
Autores: Petton, Sebastien; Pouvreau, Stephane; Dumas, Franck.
Coastal waters are subject to great environmental and anthropogenic pressures. The diffusion and the transport of these waters are a key element for environmental, ecological and economic management. There are numerous indicators of hydrological characteristics based on theories of transport time scale. However, these indicators strongly depend on the geographical shape of the studied area and tend to give information after long integration time periods, generally on the order of weeks. Here, to qualify a coastal area’s dispersion more precisely, we combined two Lagrangian approaches and estimated a local diffusivity. This paper presents the numerical implementation and the results obtained over a tidally flushed, semi-enclosed water body located at...
Tipo: Text
Palavras-chave: Hydrodynamic model; Lagrangian analysis; Barycentric repositioning method; Local diffusivity.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00609/72068/70919.pdf

Inventaire, diagnostic écologique et restauration des principaux bancs d’huitres plates en Bretagne : le projet FOREVER
Provedor de dados: 5
Autores: 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
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00505/61629/65551.pdf

Experimental shift in diet Delta13C: A potential tool for ecophysiological studies in marine bivalves
Provedor de dados: 5
Autores: Paulet, Yves-marie; Lorrain, Anne; Richard, Joëlle; Pouvreau, Stephane.
To test the potential of diet switching experiments in ecophysiological studies of marine invertebrates, stable carbon isotope ratios were measured at different seasons in the gonad, adductor muscle, digestive gland and gills of scallops (Pecten maximus) and oysters (Crassostrea gigas) held for 15 days on a constant diet of phytoplankton depleted in 13C. The aim of this study was to determine if differences in carbon incorporation could be detected among species, seasons and organs, and if so, whether it was consistent with their known energy-allocation patterns. After offering the new diet, isotope values of the different organs gradually shifted and significant differences among organs, seasons and species were found. A carbon incorporation index (CII)...
Tipo: Text
Palavras-chave: Crassostrea gigas; Pecten maximus; Carbon isotopes; Metabolism; Energy allocation.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1202.pdf

Larval recruitement of Crassostrea gigas in a french Mediterranean lagoon
Provedor de dados: 5
Autores: 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
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00165/27653/25822.pdf

Gametogenetic cycle and reproductive effort assessed by two methods in 3 age classes of Pacific oysters, Crassostrea gigas, reared in Normandy
Provedor de dados: 5
Autores: Royer, J; Seguineau, Catherine; Park, K; Pouvreau, Stephane; Choi, K; Costil, K.
Two methods were used to estimate the reproductive output of female Pacific oysters reared in Normandy: histology with image analysis and ELISA (Enzyme-Linked lmmunoSorbent Assay) which allowed the quantification of egg protein. Condition indices, gonad area and gametogenetic stages of the oysters were determined in the entire population (males and females) between May and October 2005. All investigations were performed in 3 age classes: oysters in their first, second or third years (corresponding to spat, half-grown and market-sized oysters, respectively). Both quantitative histology and ELISA provided similar results in terms of reproductive effort (illustrated by the gonado-somatic index, GSI) except during the GSI drop, corresponding to spawning, which...
Tipo: Text
Palavras-chave: Reproductive effort; Image analysis; Gametogenetic cycle; ELISA; Crassostrea gigas; Condition index.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4305.pdf

Possibilities to prevent Crassostrea gigas oyster summer mortality in France
Provedor de dados: 5
Autores: Samain, Jean-francois; Ropert, Michel; Bedier, Edouard; Soletchnik, Patrick; Mazurie, Joseph; Le Coz, Florence; Blin, Jean-louis; Mille, Dominique; Pajot, Régis; Haffray, Patrick; Bacher, Cedric; Grangere, Karine; Grangere, Karine; Pouvreau, Stephane; Bourles, Yves; Gohin, Francis; Woerther, Patrice; Boudry, Pierre.
Summer mortality has been reported in the Pacific oyster, Crassostrea gigas, for many years in Japan, US and Europe. It affects both adults and juveniles and the causes of this phenomenon are complex. Environmental, physiological or pathological putative causes were studied all over the world. Recently, the MOREST project ((MORtalitEStivale) a multidisciplinary project (2001-2005) focused on his problem led to a better understanding of this phenomenon in France. The results showed in these geographical conditions, the main interactions between the oysters, their environment and certain pathogens.
Tipo: Text
Palavras-chave: Interaction model; Environmental parameters; Summer mortality; Crassostrea gigas; Pacific oyster.
Ano: 2006
URL: https://archimer.ifremer.fr/doc/2006/acte-3476.pdf

A flow-through rearing system for ecophysiological studies of Pacific oyster Crassostrea gigas larvae
Provedor de dados: 5
Autores: Rico Villa, Benjamin; Woerther, Patrice; Mingant, Christian; Le Piver, David; Pouvreau, Stephane; Hamon, Michel; Robert, Rene.
While literature is relatively abundant on adult shellfish, ecophysiological studies at the larval stage are scarce because of both technical difficulties and inadequate methodology. A tool dedicated to provide basic information for larval ecophysiology was accordingly developed. Two steps were followed: first a flow-through method of Crassostrea gigas larval culture was perfected during a set of experiments in which rearing systems and larval density were assessed. Then a continuous hydrobiological data recorder was adapted with modifications to comply with our experimental aim. SILO (Système d'Instrumentation des Larves en flux Ouvert) allowed the successive acquisition of hydrobiological parameters in ten 150 l larval tanks in which larvae were reared...
Tipo: Text
Palavras-chave: Temperature; Ecophysiology; Bivalve larvae; Crassostrea gigas; Flow through.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4167.pdf

Table ronde : les analyses biochimiques de PLG dans la chair des coquillages
Provedor de dados: 5
Autores: Faury, Nicole; Geairon, Philippe; Moal, Jeanne; Pouvreau, Stephane; Razet, Daniel; Ropert, Michel; Soletchnik, Patrick.
Proximate biochemical analysis (proteins, lipids and carbohydrates) are performed on a regular basis by the various laboratories fom the Aquaculture Resources Directorate. Methods initially developed to analyse hydrological parameters were firstly transfered to assess meat components.1t appears now important to review and update the commonly used methods (Lowry et al., (1951), Dubois et al.,(l956), Marsh et Weinstein, (1966)), for our specifie purposes. A round table was organized to facilitate discussion among researchers and technicians from both Directorates 'Aquaculture Resources' and 'Product Valorization'and external partners, University of Caen. Several communications reviewing former and recent studies were done. Colleagues from the Directorate...
Tipo: Text
Palavras-chave: Glycogen; Carbohydrates; Lipids; Proteins; Methods comparison; Proximate biochemical composition; Glycogène; Carbohydrates; Lipiedes; Protéines; Comparaison méthodes; Composition biochimique.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/rapport-6378.pdf

Bilan 2015 du dispositif national de surveillance de la santé des mollusques marins
Provedor de dados: 5
Autores: Lupo, Coralie; Osta Amigo, Axel; Fleury, Elodie; Robert, Stephane; Garcia, Celine; Arzul, Isabelle; Baillon, Laury; Bechemin, Christian; Canier, Lydie; Chollet, Bruno; Dechamps, Lucie; Dubreuil, Christine; Faury, Nicole; Francois, Cyrille; Godfrin, Yoann; Lapegue, Sylvie; Morga, Benjamin; Travers, Marie-agnes; Tourbiez, Delphine; Masson, Jean-claude; Verin, Francoise; Cordier, Remy; Gangnery, Aline; Louis, Wilfried; Mary, Charlotte; Normand, Julien; Penot, Julia; Cheve, Julien; Dagault, Francoise; Le Jolivet, Aurore; Le Gal, Dominique; Lebrun, Luc; Bellec, Gwenael; Bouget, Jean-francois; Cochennec-laureau, Nathalie; Palvadeau, Hubert; Grizon, James; Chabirand, Jean-michel; Pepin, Jean-francois; Seugnet, Jean-luc; D'Amico, Florence; Maurer, Daniele; Le Gall, Patrik; Mortreux, Serge; Baldi, Yoann; Orsoni, Valerie; Bouchoucha, Marc; Le Roy, Valerian; Pouvreau, Stephane; Queau, Isabelle; Lamoureux, Alice.
Depuis 1992, la surveillance de la santé des mollusques marins du littoral français est assurée par le réseau de Pathologie des Mollusques (Repamo). Ses activités s’inscrivent dans le cadre de la Directive Européenne 2006/88/CE. Depuis son évaluation par la plateforme nationale d’épidémiosurveillance en santé animale en 2012, l’objectif de surveillance est la détection précoce des infections dues à des organismes pathogènes exotiques et émergents affectant les mollusques marins sauvages et d’élevage. L’année 2015 est la première année de transition pour laquelle un début d’évolution des modalités de surveillance de la santé des mollusques marins animées par l’Ifremer a été amorcé. Un dispositif hybride de surveillance a été mis en place, s’appuyant sur...
Tipo: Text
Palavras-chave: Réseau; Surveillance; Pathologie; Mollusques; Coquillages; Santé; Mortalité; Maladie.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00324/43486/42945.pdf

Suivi national des mortalités au stade naissain d'un lot témoin et d'un lot à survie améliorée pour Crassostrea gigas
Provedor de dados: 5
Autores: Degremont, Lionel; Maurouard, Elise; Nourry, Max; Seugnet, Jean-luc; Bedier, Edouard; Fleury, Elodie; Langlade, Aime; Pernet, Fabrice; Pouvreau, Stephane; Le Souchu, Pierrick; Normand, Julien; D'Amico, Florence; Rumebe, Myriam; Cantin, Christian; Barret, Jean; Le Gall, Patrik; Baud, Jean-pierre; Cochennec-laureau, Nathalie; Gervasoni, Erika; Pelissier, Pablo.
Ce rapport présente la comparaison des mortalités de deux lots de naissains de Crassostrea gigas dans plusieurs bassins conchylicoles et déterminer le gain de survie obtenu par la sélection pour des huîtres diploïdes
Tipo: Text
Palavras-chave: Mortalités; Huître creuse; Crassostrea gigas; Sélection génétique; Naissain.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00065/17644/15180.pdf

Caractéristiques biologiques des gamètes et larves d'huître plate européenne (Ostrea edulis): données préliminaires
Provedor de dados: 5
Autores: Suquet, Marc; Queau, Isabelle; Le Grand, Jacqueline; Ratiskol, Dominique; Pouvreau, Stephane.
      The biology of gametes and larvae in brooding mollusc species remains little explored. The aim of this study is to present the results obtained in 2016, on biological characteristics of gametes and larvae of European flat oyster.       Measurements were carried out on 50 oysters, collected by divers in the Rade de Brest (Finistère, France), during the spawning period of this species. Gonad pH is acidic (6.58±0.54). After the dissociation of spermatozeugmata, an acellular structure to which the spermatozoa are clustered, the percentage of motile spermatozoa ranged from 20 to 34% and the Velocity of the Average Path from 70 to 85µm/s. Spermatozeugmata were shed after serotonin injection. Oocytes (mean diameter: 129.4±19.1µm) were rarely observed (2...
Tipo: Text
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00383/49390/49803.pdf

Modelling growth and reproduction of the Pacific oyster Crassostrea gigas: Advances in the oyster-DEB model through application to a coastal pond
Provedor de dados: 5
Autores: 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, 156–167.] 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

Growth of the Pacific oyster (Crassostrea gigas) in a high-turbidity environment: Comparison of model simulations based on scope for growth and dynamic energy budgets
Provedor de dados: 5
Autores: Barille, Laurent; Lerouxel, Astrid; Dutertre, Mickael; Haure, Joel; Barille, Anne-laure; Pouvreau, Stephane; Alunno-bruscia, Marianne.
We compared growth simulations by dynamic energy budget (DEB) and scope for growth (SFG) models of the Pacific oyster Crassostrea gigas, cultivated in Bourgneuf Bay on the French Atlantic coast. This bay is located at a latitude in the middle of the European range of the species, and is characterized by high concentrations of suspended particulate matter (SPM) and a marked gradient between high-turbidity sites in the north (daily SPM &gt; 500 mg L-1) and intermediate-turbidity sites in the south. The models use two forcing variables: seawater temperature and food density. We tested two indices of food availability: chlorophyll a and microalgal concentrations. In the SFG model, food intake is simulated by a type-II Holling functional response, as in the DEB...
Tipo: Text
Palavras-chave: Oyster; Dynamic Energy Budget model; Scope for growth model; Turbidity.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00043/15433/12783.pdf

Noninvasive characterization of gonad maturation and determination of the sex of Pacific oysters by MRI
Provedor de dados: 5
Autores: 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

Observatoire national du cycle de vie de l’huître creuse en France. Rapport annuel ECOSCOPA 2018
Provedor de dados: 5
Autores: Fleury, Elodie; Petton, Sebastien; Corporeau, Charlotte; Gangnery, Aline; Pouvreau, Stephane.
Occupying a prime position in the French coastal landscape, oyster farming is the leading contributor to the French aquaculture sector with an estimated production of 85,000 tonnes in recent years. However, since 2008, this species has been affected by recurrent massive mortality episodes triggered by the presence of viral infectious agents (of the type Herpes virus OsHV-1 μVar) in conjunction with environmental factors (i.e. temperature rise). This viral infection induces an alteration of the antimicrobial defenses and a destabilization of its microbiota. This process leads to secondary infection by opportunistic bacteria that are potentially pathogenic and multiply rapidly, causing irreversible tissue damage leading to the death of the animal. At the...
Tipo: Text
Palavras-chave: Huître creuse; Physiologie; Génétique; Écologie; Réseau National.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00634/74654/74826.pdf

Forty questions of importance to the policy and practice of native oyster reef restoration in Europe
Provedor de dados: 5
Autores: Zu Ermgassen, Philine S. E.; Bonačić, Kruno; Boudry, Pierre; Bromley, Cass A.; Cameron, Tom C.; Colsoul, Bérenger; Coolen, Joop W. P.; Frankić, Anamarija; Hancock, Boze; Have, Tom M.; Holbrook, Zoë; Kamermans, Pauline; Laugen, Ane T.; Nevejan, Nancy; Pogoda, Bernadette; Pouvreau, Stephane; Preston, Joanne; Ranger, Christopher J.; Sanderson, William G.; Sas, Hein; Strand, Åsa; Sutherland, William J.
Oyster reefs are among the most threatened marine habitats globally. In Europe, oyster reefs have been extirpated from most locations within their historical range. Active restoration of the native oyster (Ostrea edulis) in Europe has grown substantially in recent years. In sharing experiences between oyster restoration projects in Europe at the Native Oyster Restoration Alliance conference, NORA2, in Edinburgh in May 2019, it became apparent that a number of similar barriers are experienced. This study identified the top 40 questions, which, if answered, would have the greatest influence on the policy and practice of oyster restoration in Europe. Initially 71 people were consulted across 28 institutions and 11 European countries to generate 194 questions....
Tipo: Text
Palavras-chave: Alien species; Estuary; Fishing; Invertebrates; Pollution; Restoration; Subtidal.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00658/77004/78261.pdf

Estimation de la biomasse d'huîtres non cultivées dans le bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Prou, Jean; Pouvreau, Stephane; Renaud, Vivian.
In the Marennes-Oléron oyster culture basin, the cultivated oyster stock shows an unbalanced age distribution: 25 000 to 30 000 tonnes are commercialized each year for a total cultivated biomass of 95 000 tonnes (1993). The biological overexploitation of the basin requires a reduction of the stock in order to get back to productivity rates that are compatible with the restrictions of the oyster market. This study gives an estimated natural deposit biomass of around 3 000 tonnes. An estimate of the abandoned and wild oyster biomass shows that 20 000 tonnes of these animals can be considered as competitors to cultivated oysters. [...].
Tipo: Text
Palavras-chave: Bassin Marennes Oléron; Echantillonnage; Estimation; Répartition spatiale; Typologie; Biomasse; Crassostrea gigas; Huîtres.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/rapport-4741.PDF

DIversification de la pêcherie de la RAde de Brest par l'étude de semis de PEtoncle Noir : le projet DIRAPEN
Provedor de dados: 5
Autores: Pouvreau, Stephane.
Comme de nombreuses espèces d’invertébrés marins natifs de nos côtes, le pétoncle noir (Mimachlamys varia) connaît, depuis 30 ans, une très forte diminution de son abondance avec une disparition progressive des gisements sauvages autrefois réputés. Dans ce contexte, le développement d’une activité de « Sea ranching » peut être une piste intéressante pour soutenir certaines pêcheries côtières, comme c’est le cas pour la coquille Saint Jacques en rade de Brest depuis les années 1990. L’objectif du projet DIRAPEN était donc de lancer à nouveau, en 2015 et sur le site pilote de rade de Brest, des opérations de semis de naissains de pétoncles noirs afin d'étudier les conditions d’un soutien au stock pour cette espèce. Ce rapport présente l’accompagnement...
Tipo: Text
Palavras-chave: Pétoncle; Mimachlamys varia; Sea Ranching; Semis; Restauration écologique; Rade de Brest (France); Variegated Scallop; Mimachlamys varia; Sea Ranching; Shellfish mariculture; Ecological restoration; Bay of Brest (France).
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00363/47425/47446.pdf

By-catch and Discarding in Pelagic Trawl Fisheries
Provedor de dados: 5
Autores: Morizur, Yvon; Tregenza, N; Heessen, H; Beerow, S; Pouvreau, Stephane.
Incidental mammal catch and the composition of the fish catch were studied in pelagic trawl fisheries in the North-East Atlantic. Several seasonal European fisheries were investigated with scientific observation on the fishing vessels. A total of 379 days at sea were observed . The sampled fisheries were horsemackerel (Dutch, French), herring (Irish), mackerel (UK), pilchard (UK , French) and other French fisheries (hake, tuna, bass, black bream, anchovy). Unintentional catches of dolphins were recorded in four of the investigated fisheries (Dutch horsemackerel, French tuna, French hake and French sea bass) at a rate of 1 dolphin per 100 tow hours; Grey seals were caught in the Irish herring fishery at a rate of 4 individuals per 100 tow hours. The fish...
Tipo: Text
Palavras-chave: Albacore; Bluefin tuna Bass Black bream Whiting Hake Anchovy Pilchard Mackerel Horsemackerel Seal Cetacean Incidental mammal catch Reasons for discarding Discards By catch Pelagic trawl.
Ano: 1996
URL: https://archimer.ifremer.fr/doc/1996/rapport-1236.pdf

Etude de la connectivité potentielle en rade de Brest : application au cas de l'huître plate, Ostrea edulis
Provedor de dados: 5
Autores: Bernard, Ismael; Duchene, Julie; Hily, Christian; Lazure, Pascal; Pouvreau, Stephane; Boudry, Pierre.
En complément du rapport final (Anonyme (2014). PERLE. Programme d'expérimentation et de recherche sur l'huître plate Ostrea edulis. Rapport final de l'ensemble du projet 2011-2014. http://archimer.ifremer.fr/doc/00248/35932/), ce rapport présente l'étude de la phase de dispersion des larves en rade de Brest et analyse le lien entre la quantité de larves émises et la quantité de larves captées. Ce lien, qui possède une forte composante spatiale, est appelé connectivité. Il est sous l’influence de la dispersion et de la survie des larves mais seule la dispersion larvaire, avec différents forçages biophysiques du milieu, a été considérée ici. Les effets de la localisation des zones d’émission et de captage, du comportement des larves, du vent ou de la durée...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00251/36233/34793.pdf

Les rejets dans la pêche artisanale de Manche occidentale
Provedor de dados: 5
Autores: 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 (&lt;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

A box-model of carrying capacity of the Thau lagoon in the context of ecological status regulations and sustainable shellfish cultures
Provedor de dados: 5
Autores: Pete, Romain; Guyondet, Thomas; Bec, Beatrice; Derolez, Valerie; Cesmat, Ludovic; Lagarde, Franck; Pouvreau, Stephane; Fiandrino, Annie; Richard, Marion.
The decrease of microbial and nutrient inputs from the watershed has long dominated lagoon ecosystem management objectives. Phytoplankton biomass and abundance have drastically decreased for more than a decade and Zostera meadow have gradually recovered, expressing lagoon ecosystem restoration such as Thau lagoon. Do the progressive achievement of the good ecological status of the Thau lagoon possibly threatens the shellfish industry in terms of production and oyster quality, by reducing the carrying capacity? To provide answers about the right balance to be achieved between conservation and exploitation, a new numerical tool was developed to help in decision-making. We hereby propose to incorporate a Dynamic Energy Budget type shellfish production model...
Tipo: Text
Palavras-chave: Shellfish farming; Carrying capacity; Stakeholder implication; Nitrogen and phosphorus inputs; Water frame directive; Ecological indicators; Phytoplankton depletion; Coupled biogeochemical-deb model.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00622/73395/75312.pdf

An eDNA/eRNA‐based approach to investigate the life cycle of non‐cultivable shellfish micro‐parasites: the case of   Bonamia ostreae   , a parasite of the European flat oyster   Ostrea edulis
Provedor de dados: 5
Autores: Mérou, Nicolas; Lecadet, Cyrielle; Pouvreau, Stephane; Arzul, Isabelle.
Environmental DNA approaches are increasingly used to detect microorganisms in environmental compartments, including water. They show considerable advantages to study non‐cultivable microorganisms like Bonamia ostreae, a protozoan parasite inducing significant mortality in populations of flat oyster Ostrea edulis . Although B. ostreae development within the host has been well described, questions remain about its behaviour in the environment. As B. ostreae transmission is direct, seawater appears as an interesting target to develop early detection tools and improve our understanding of disease transmission mechanisms. In this context, we have developed an eDNA/eRNA approach allowing detecting and quantifying B. ostreae 18S rDNA/rRNA as well as monitoring...
Tipo: Text
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00636/74800/75174.pdf

Oysters as sentinels of climate variability and climate change in coastal ecosystems
Provedor de dados: 5
Autores: Thomas, Yoann; Cassou, Christophe; Gernez, Pierre; Pouvreau, Stephane.
Beyond key ecological services, marine resources are crucial for human food security and socio-economical sustainability. Among them, shellfish aquaculture and fishing are of primary importance but become more vulnerable under anthropogenic pressure, as evidenced by reported mass mortality events linked to global changes such as ocean warming and acidification, chemical contamination, and diseases. Understanding climate-related risks is a vital objective for conservation strategies, ecosystems management and human health. We provide here a comprehensive study of the historical mortality of adult oysters related to observed climate variability along the French Atlantic coast from 1986 to 2015, and we built on this knowledge to develop hindcast and forecast...
Tipo: Text
Palavras-chave: North Atlantic; Weather regime; Oyster; Monitoring network; Mortality risk assessment; Climate models; RCP scenarios.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00461/57255/59281.pdf

BABE : Comparaison des sites de Ronce et Baie de Veys, incidence sur la reproduction et les mortalités : Ecologie côtière, mortalités, croissance, environnement - Physiologie - Immunologie
Provedor de dados: 5
Autores: Soletchnik, Patrick; Le Moine, Olivier; Faury, Nicole; Guilpain, Patrice; Geairon, Philippe; Razet, Daniel; Seugnet, Jean-luc; Robert, Stephane; Ropert, Michel; Simonne, Charlotte; Hugonnet, Virginie; Moal, Jeanne; Pouvreau, Stephane; Huvet, Arnaud; Samain, Jean-francois; Lambert, Christophe; Soudant, Philippe; Frouel, Stephane; Choquet, Gwenaelle; Delaporte, Maryse; Paillard, Christine.
Four laboratories are involved in this multidisciplinary study: the Conchological Laboratory of Normandie (LCN), the Invertebrates Physiology Laboratory (LPI), the Université Bretagne Occidentale (LEMAR IHP) and the Conchological Laboratory of Poitou-Charentes (LCPC). The part of the study which is presented here (thematics "Coastal ecology") was produced in collaboration with the LCN. The data on the Bay of Veys was collected by Michel Ropert. This study aims at observing the "sites" effect on mortality and on the general biology of the animal, as well as measuring some environmental elements (e.g. water temperature, etc.). The geographical sites are Gefosse in the Bay of Veys (East Cotentin) and the Ronce bank in the south of the Marennes Oléron Bay. The...
Tipo: Text
Palavras-chave: Immunologie; Physiologie; Paramètres environnementaux; Croissance; Ecologie côtière; Baies des Veys Cotentin; Ronce   Charente Maritime; Comparaison sites; Reproduction; Mortalités; Crassostrea gigas; Huîtres.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/acte-3405.pdf

Etude et modélisation des mécanismes impliqués dans la croissance de l'huître perlière, Pinctada margaritifera, au sein de l'écosystème conchylicole du lagon de l'atoll de Takapoto (Polynésie Française)
Provedor de dados: 5
Autores: Pouvreau, Stephane.
L'huître perlière, Pinctada margaritifera (Linné, 1758) var. cumingi (Reeve), productrice de perles noires, fait l' objet d'une aquaculture florissante en Polynésie Française. Afin de pérenniser cette activité, un programme de recherche (le PGRN) a été lancé, en 1990, sur l' atoll de Takapoto. L' un des thèmes de ce programme réside dans l'étude de la capacité trophique d'un lagon soumis à une activité de perliculture. A cet égard, un modèle déterministe expliquant la croissance et la reproduction de P. margaritifera à partir des paramètres du milieu (notamment la nourriture disponible) a été mis au point. La construction de ce modèle a impliqué : ( 1) l'analyse de l'hydrobiologie du lagon; (2) l'étude de la physiologie de P. margaritifera; (3) le sui vi...
Tipo: Text
Palavras-chave: Bivalves; Huîtres perlières; Pinctada margaritifera; Physiologie; Croissance; Reproduction; Hydrobiologie; Atoll; Lagon; Écosystème; Réseau trophique; Modélisation; Capacité trophique; Polynésie française; Bivalves; Pearl oyster; Pinctada ma rgaritifera; Physiology; Growth; Reproduction; Hydrobiology; Atoll; Lagoon; Ecosystem; Trophic web; Modelling; Carrying capacity; French Polynesia.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00034/14558/11856.pdf

Investigation of marine bivalve morphology by in vivo MR imaging: first anatomical results of a promising technique
Provedor de dados: 5
Autores: 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

Oyster (c. gigas) recruitment in Mediteranean lagoons ; new approaches for studying larval connectivity using MARS3D modeling tools
Provedor de dados: 5
Autores: Ubertini, Martin; Fiandrino, Annie; Bernard, Ismael; Thomas, Yoann; Dumas, Franck; Pouvreau, Stephane; Roque D'Orbcastel, Emmanuelle; Lagarde, Franck.
The Thau lagoon, located at the South of France, provides 10% of the French pacific oyster Crassostrea gigas production (Robert et al., 2013). Despite this intensive shellfish production, the larval recruitment of this species within the Thau lagoon is still misunderstood and spat collection remains highly variable; as a consequence, shellfish farmers rely mostly on hatchery's spat. In 2012, the PRONAMED II project was launched, aiming to improve our understanding of the C. gigas reproductive cycle within Mediterranean lagoons and to explore the feasibility for oyster-spat collecting. In addition to an extensive sampling work encompassing both spatial and temporal features of larval recruitment, we tried to understand the contribution of larval dispersal...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00248/35905/34427.pdf

Inventaire, diagnostic écologique et restauration des principaux bancs d’huitres plates en Bretagne : le projet FOREVER
Provedor de dados: 5
Autores: 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...
Tipo: Text
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00683/79506/82154.pdf

Synthèse PERLE. Programme d’Expérimentation et de recherche sur L’huître plate ostrea Edulis
Provedor de dados: 5
Autores: Hussenot, Mathieu; Pouvreau, Stephane; Duchene, Julie; Freulon, Henry; Arzul, Isabelle; Lapegue, Sylvie.
En complément du rapport final (Anonyme (2014). PERLE. Programme d'expérimentation et de recherche sur l'huître plate Ostrea edulis. Rapport final de l'ensemble du projet 2011-2014. http://archimer.ifremer.fr/doc/00248/35932/), ce document présente une synthèse des principaux résultats du programme PERLE et ouvre de multiples perspectives pour les années à venir.
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00249/36060/34610.pdf

Effect of environmental drivers on the reproduction of the pacific oyster Crassostrea gigas in the Mediterranean: The case of the Thau lagoon
Provedor de dados: 5
Autores: Ubertini, Martin; Lagarde, Franck; Le Gall, Patrik; Mortreux, Serge; Pernet, Fabrice; Fiandrino, Annie; Pouvreau, Stephane; Roque D'Orbcastel, Emmanuelle.
The aquaculture of the oyster Crassostrea gigas is largely based on natural recruitment of the species on spat collectors along the french Atlantic coast, the remaining spat being provided by hatcheries and nurseries. Due to an increase in the climate/meteorological variability, during the last twenty years, the natural spat collection has become variable, from null to overabundant depending on the year. Since 2008, the oyster spat mortalities worsen the situation, reducing the available spat and increasing the cost of the latter. However, the temporal variability of the natural recruitment modalities in the Mediterranean do not allow the aquaculture industry to rely on native spats, making the understanding of natural recruitment in the Mediterranean a...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00248/35894/34422.pdf

Trophic environments influence size at metamorphosis and recruitment performance of Pacific oysters
Provedor de dados: 5
Autores: Lagarde, Franck; Richard, Marion; Bec, Beatrice; Roques, Cecile; Mortreux, Serge; Bernard, Ismael; Chiantella, Claude; Messiaen, Gregory; Nadalini, Jean-bruno; Hori, Masakazu; Hamaguchi, Masami; Pouvreau, Stephane; Roque D'Orbcastel, Emmanuelle; Tremblay, Rejean.
Reproduction and recruitment of benthic invertebrates are influenced by the climate and by the ecological structure of marine ecosystems, along with local anthropogenic pressures such as eutrophication or oligotrophication. Using the Pacific oyster Crassostrea gigas as a biological model, we tested the hypothesis that the variability in prodissoconch II (PII) size (i.e. size at metamorphosis) depends on ecological functioning. Settlement and recruitment were assessed at 5 sampling sites on the French Mediterranean shellfish farmed Thau lagoon during the main summer recruitment events in 3 consecutive years (2012-2014). Hydrobiological and planktonic analyses were conducted at 3 sampling sites. Our results showed that recruitment was extremely...
Tipo: Text
Palavras-chave: Larval ecology; Recruitment; Prodissoconch II; Crassostrea gigas; Oligotrophication; Cryptophytes; Thau lagoon.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00454/56613/58334.pdf

Global change and climate-driven invasion of the Pacific oyster (Crassostrea gigas) along European coasts: a bioenergetics modelling approach
Provedor de dados: 5
Autores: Thomas, Yoann; Pouvreau, Stephane; Alunno-bruscia, Marianne; Barille, Laurent; Gohin, Francis; Bryere, Philippe; Gernez, Pierre.
Aim  The spread of non-indigenous species in marine ecosystems world-wide is one of today's most serious environmental concerns. Using mechanistic modelling, we investigated how global change relates to the invasion of European coasts by a non-native marine invertebrate, the Pacific oyster Crassostrea gigas.  Location Bourgneuf Bay on the French Atlantic coast was considered as the northern boundary of C. gigas expansion at the time of its introduction to Europe in the 1970s. From this latitudinal reference, variations in the spatial distribution of the C. gigas reproductive niche were analysed along the north-western European coast from Gibraltar to Norway.  Methods The effects of environmental variations on C. gigas physiology and phenology were studied...
Tipo: Text
Palavras-chave: Biogeographical range expansion; Crassostrea gigas; DEB model; European coasts; Functional traits; Global change; Individual-based model; Invasive species; Remote-sensing.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00287/39828/38459.pdf

Reproduction de l’huître creuse, Crassostrea gigas, en Baie de Bourgneuf : Mise en place d’un suivi en 2009 dans le cadre du projet national Velyger
Provedor de dados: 5
Autores: Pouvreau, Stephane; Le Souchu, Pierrick; Breerette, Stephane; Claude, Serge; Langlade, Aime; Bouget, Jean-francois; Hitier, Benoist; Martin, Anne-genevieve; Bedier, Edouard.
Dans le cadre d’un réseau national (VELYGER), la Baie de Bourgneuf (partie Nord de la Baie) a fait l’objet en 2009 d’un suivi détaillé de la reproduction de l’huître creuse, Crassostrea gigas : gamétogenèse et ponte des adultes, abondance et développement larvaire ainsi qu’intensité et survie du captage sur collecteurs. Les résultats de ce suivi ont été mis en ligne, sous la forme de bulletin hebdomadaire, en temps quasi-réel sur le site : http://www.ifremer.fr/velyger. Il ressort, en 2009, que : (1) la gamétogenèse des huîtres s’est déroulée favorablement en permettant une ponte massive dans la première quinzaine de juillet, plus précoce mais aussi plus importante que sur des sites traditionnels (Arcachon et Marennes-Oléron) ; (2) les larves ont été...
Tipo: Text
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00011/12273/9064.pdf

Application of a dynamic energy budget model to the Pacific oyster, Crassostrea gigas, reared under various environmental conditions
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bourles, Yves; Lefebvre, Sebastien; Gangnery, Aline; Alunno-bruscia, Marianne.
The Dynamic Energy Budget (DEB) model (Kooijman, S.A.L.M., 1986. Energy budgets can explain body size relations. J. Theor. Biol. 121, 269¿282; Kooijman, S.A.L.M., 2000. Dynamic Energy and Mass Budgets in Biological Systems. Cambridge University Press, Cambridge, 424 pp.) has been adapted to describe the dynamics of growth and reproduction of the Pacific oyster (Crassostrea gigas) reared in different areas under conditions ranging from controlled to natural. The values of the model parameters were estimated from available physiological data and from published information. The sets of data used to validate the model came from three long-term growth experiments (&gt; 5 months) performed on Pacific oysters reared under different conditions of food and...
Tipo: Text
Palavras-chave: Reproductive effort; Reproduction; Growth; Ecophysiology; Dynamic energy budget; Crassostrea gigas.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1817.pdf

Addressing critical limitations of oyster (   Ostrea edulis   ) restoration: Identification of nature‐based substrates for hatchery production and recruitment in the field
Provedor de dados: 5
Autores: Colsoul, Bérenger; Pouvreau, Stephane; Di Poi, Carole; Pouil, Simon; Merk, Verena; Peter, Corina; Boersma, Maarten; Pogoda, Bernadette.
The European flat oyster (Ostrea edulis) is an ecosystem engineer that provides important biogenic reef habitat with associated ecosystem functions and services. Most stocks have been commercially exploited and degraded; some are functionally extinct. Ecological restoration now aims to recover these degraded, damaged or destroyed ecosystems. Availability of seed oysters and substrate for successful larval recruitment has been identified as a major limiting factor for restoration projects in Europe. In substrate‐limited areas, restoration approaches have to involve the restoration of suitable substrates. The present study provides an evaluation of such potential substrate types. Various categories were investigated through hatchery and/or field experiments:...
Tipo: Text
Palavras-chave: Coastal; Invertebrates; Restoration; Settlement; Substrates.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00658/77058/78357.pdf

Effect of environmental and nutritive conditionings on defense mechanisms of oyster Crassostrea gigas during an annual cycle
Provedor de dados: 5
Autores: Delaporte, Maryse; Moal, Jeanne; Soudant, Philippe; Lambert, Christophe; Pouvreau, Stephane; Enriquez, Martha; Degremont, Lionel; Soletchnik, Patrick; Gagnaire, Beatrice; Ropert, Michel.
In the frame of MOREST project, a common biological material, resulting of a mixture of different families produced in experimental hatchery, was reared in two different environmental fields : Normandy and Charente. Concomitantly, a pool was conditioned at the Ifremer Argenton hatchery with three different algae levels : 4%, 8% and 12% of algal dry weight per oyster dry weight. During the experiments, five immune parameters were studied in parallel with survival rate and reproductive status (stages and intensity). Site location, seasonal variations and experimental diet level clearly influenced oyster immune parameters. Haemocyte counts were higher for oysters reared in Normandy than those reared in Charente and in hatchery. Granulocyte percentage was...
Tipo: Text
Palavras-chave: Defense mechanisms; Nutrition; Seasonal variations; Physiology; Crassostrea gigas; Pacific oysters.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3500.pdf

PERLE - Programme d'expérimentation et de recherche sur l'huître plate Ostrea edulis - Rapport final des sous-programmes 2 et 3
Provedor de dados: 5
Autores: Arzul, Isabelle; Baillon, Laury; Boudry, Pierre; Bouget, Jean-francois; Chollet, Bruno; Cochet, Helene; Couraleau, Yann; Dubreuil, Christine; Duchene, Julie; Dutartre, Julie; Garcia, Celine; Heloury, Purotu; Heurtebise, Serge; Huchet, Eve; Hussenot, Mathieu; Langlade, Aime; Ollier, Simon; Omnes, Emmanuelle; Pouvreau, Stephane; Roby, Charlotte; Serpin, Delphine; Viard, Frederique; Wacrenier, Candice; Lapegue, Sylvie.
L’huître plate (Ostrea edulis) est une espèce endémique des côtes européennes, elle est présente depuis des millions d’années. Son aire de répartition est très vaste allant de la Norvège jusqu’au Maroc. Elle est également présente en mer Méditerranée, en mer Noire, mais également au Canada, aux Etats-Unis ou encore en Afrique du Sud, à la suite d'introductions pour des raisons aquacoles. En France, à partir de la fin des années 70, de fortes mortalités ont été constatées sur les bancs naturels et en élevage, faisant rapidement chuter la production de 20 000 tonnes à 2 000 tonnes. Ces mortalités ont été attribuées à deux maladies parasitaires : la marteiliose (due au parasite Marteilia refringens) et la bonamiose (due au parasite Bonamia ostreae). Trente...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00247/35815/34328.pdf

Genetic and reproduction strategy in Crassostrea gigas mortality
Provedor de dados: 5
Autores: Moal, Jeanne; Bedier, Edouard; Fleury, Pierre-gildas; Langlade, Aime; Le Coguic, Yvette; Degremont, Lionel; Boudry, Pierre; Le Coz, Jean-rene; Pouvreau, Stephane; Enriquez-diaz, M.; Lambert, Christophe; Quere, Christele; Soudant, Philippe; Samain, Jean-francois.
Bi-parental families were produced in hatchery and tested in the field in 2001. Two sets of 5 families were constituted, selected on their high (R) and low (S) survival. These two sets were reared in Brittany from March to November 2002. Samplings were performed twice a month to obtain data on biometry, survival, reproductive cycle, biochemical composition, adenylate energy charge, hemolymph parameters (ions and defense system) and muscle strength. "R" and "S" oysters exhibited different reproductive effort and spawning strategy. "R" oysters allocated less energy in gonad than "S" ones and presented a complete spawning at the end of August contrary to the "S" which spawns partially. Mortality started in July when the seawater temperature reached 19 degree...
Tipo: Text
Palavras-chave: Summer; Reproduction; Oyster culture; Mortality; Genetic diversity; Commercial species; Breeding.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3345.pdf

Modelling growth and reproduction in the Pacific oyster Crassostrea gigas : 1. What's new with the oyster-DEB model?
Provedor de dados: 5
Autores: Bourles, Yves; Pouvreau, Stephane; Alunno-bruscia, Marianne; Leguay, Didier; Arnaud, Christophe; Goulletquer, Philippe; Kooijman, S. A. L. M.
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/acte-3330.pdf

In situ spawning in a marine broadcast spawner, the Pacific oyster Crassostrea gigas : Timing and environmental triggers
Provedor de dados: 5
Autores: Bernard, I.; Massabuau, J. -c.; Ciret, P.; Sow, M.; Sottolichio, Aldo; Pouvreau, Stephane; Tran, D.
The precise environmental conditions under which broadcast spawners spawn in the field remain largely unknown. We investigated this issue in the oyster Crassostrea gigas using three different methods at different time scales in two traditional oyster farming areas of the French Atlantic Coast, the Bay of Arcachon and Marennes-Oléron. We directly recorded spawning at high temporal resolution using high-frequency non-invasive (HFNI) valvometry from 2007–2014 and measured the dry mass and oyster larvae abundance in 2008 and 2009. We analyzed a 29-yr series of oyster D-larvae numbers in the Bay of Arcachon (1982–2010). By combining these three approaches, we demonstrated that during the summer months at both sites, spawning in C. gigas occurs in the morning or...
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00312/42335/41666.pdf

Projet Velyger (2008-2010) : Observer, Analyser et Gérer la variabilité du recrutement de l’huître creuse en France. Rapport de synthèse
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bernard, Ismael; Le Souchu, Pierrick; Huvet, Arnaud; Talarmain, Eric; Auby, Isabelle; Maurer, Daniele; Barbier, Claire; Tournaire, Marie-pierre; D'Amico, Florence; Rumebe, Myriam; Neaud-masson, Nadine; Bedier, Edouard; Martin, Anne-genevieve; Claude, Serge; Langlade, Aime; Bouget, Jean-francois; Hitier, Benoist; Stanisiere, Jean-yves; Breerette, Stephane; Robert, Stephane; Guilpain, Patrice; Seugnet, Jean-luc; Guesdon, Stephane; Soletchnik, Patrick; Le Moine, Olivier; Dumas, Franck; Quemener, Loic; Barbot, Stephane; Repecaud, Michel; Mille, Dominique; Geay, A; Bouquet, Anne-lise.
L’ostréiculture constitue la principale activité aquacole française. Cette activité de quasi-monoculture, basé sur l’élevage de l’huître creuse, Crassostrea gigas, repose en grande partie sur le recrutement naturel de l’espèce qui assure 70% des besoins en jeunes huîtres (naissain). Or, depuis une dizaine d'années, dans les bassins d'Arcachon et de Marennes-Oléron, principaux centres de captage français pour l’huître creuse, la collecte du naissain ou captage devient encore plus variable qu’auparavant: à des années de captage presque nul (par exemple les années 2002, 2005, 2007) succèdent des années où il est surabondant (par exemple les années 2003 ou 2006). En parallèle, et probablement en raison du progressif réchauffement des eaux, la reproduction de...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00054/16489/13995.pdf

A comparative ecophysiological study of two infaunal filter-feeding bivalves: Paphia rhomboides and Glycymeris glycymeris
Provedor de dados: 5
Autores: Savina, Marie; Pouvreau, Stephane.
A comparative ecophysiological study was carried out in September and November 2002 for two bivalves, Paphia rhomboides and Glycymeris glycymeris, which are significantly harvested in the Western Channel (French coast). Individual measurements of clearance and respiration rates were performed for both species, in several experimental conditions of temperature and phytoplankton concentrations. Those conditions were chosen to be in the range of those commonly observed in the subtidal area of the Western Channel. The mean value of clearance rate and oxygen consumption obtained from continuous data recording did not reveal any significant influence of temperature in the investigated range, but a significant difference between P rhomboides and G. glycymeris....
Tipo: Text
Palavras-chave: Filter feeding; Bivalves; Glycymeris glycymeris; Paphia rhomboides; Scope for growth; Ecophysiology.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-379.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2012
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bellec, Gwenael; Le Souchu, Pierrick; Queau, Isabelle; Talarmain, Eric; Alunno-bruscia, Marianne; Auby, Isabelle; Maurer, Daniele; Barbier, Claire; Tournaire, Marie-pierre; D'Amico, Florence; Rumebe, Myriam; Fleury, Elodie; Langlade, Aime; Bouget, Jean-francois; Collin, Karine; Fortune, Mireille; Hitier, Benoist; Bedier, Edouard; Robert, Stephane; Guilpain, Patrice; Grizon, James; Seugnet, Jean-luc; Guesdon, Stephane; Lagarde, Franck; Le Gall, Patrik; Messiaen, Gregory; Roque D'Orbcastel, Emmanuelle; Gohin, Francis; Bryere, Philippe; Quemener, Loic; Repecaud, Michel; Bucas, Karenn; Barbot, Stephane; Guillemot, Anne; Nonnotte, Lidwine; Duros, Wenceslas; Bonnat, Armel; Tarot, Stephane; Mille, Dominique; Geay, Amelie; Bouquet, Anne-lise.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage.  Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le Bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple les années 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (les années 2003, 2006, 2008, 2012). A Marennes-Oléron, cette variabilité existe, mais s’avère...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00135/24648/22681.pdf

National observation infrastructures in a European framework: COAST-HF A fixed-platform network along French coasts
Provedor de dados: 5
Autores: 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
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00635/74723/74708.pdf

Conséquences du changement climatique sur les écosystèmes marins exploités par la pêche et la conchyliculture
Provedor de dados: 5
Autores: Petitgas, Pierre; Ulrich, Clara; Auber, Arnaud; Gourguet, Sophie; Huret, Martin; Mazurais, David; Pernet, Fabrice; Pouvreau, Stephane; Richard, Marion; Servili, Arianna; Thebaud, Olivier; Zambonino Infante, Jose-luis.
Tipo: Text
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00657/76942/78148.pdf

Évaluation des potentialités de l'IRM pour la recherche sur la Physiologie des Bivalves Premiers résultats anatomiques et perspectives
Provedor de dados: 5
Autores: Pouvreau, Stephane; Davenel, A; Quellec, S; Rambeau, M.
Nuclear Magnetic Resonance (NMR) is increasingly used in biology and the appearance of imaging and structural and/or metabolic spectroscopy (MRI/MSR) platforms (Rennes, Strasbourg, Marseille...) devoted to this small animal shows the recent keen interest in these research techniques. However, to this day and to our knowledge, no approach of this style has been developed for sea molluscs and even less so for the cup oyster, Crassostrea gigas. Because of its economic importance, this bivalve mollusc is the subject of much research in physiology, to the point of becoming, at IFREMER, a biological model for marine invertebrates. Nonetheless, most of the methodologies developed for studying it are destructive, which (1) prevents individual follow-up, (2)...
Tipo: Text
Palavras-chave: Nuclear Magnetic Resonance; Anatomy; Biometry; Physiology; Bivalvia.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/rapport-1560.pdf

Gametogenesis, spawning behavior and larval abundance of the Pacific oyster Crassostrea gigas in the Thau lagoon: Evidence of an environment-dependent strategy
Provedor de dados: 5
Autores: Ubertini, Martin; Lagarde, Franck; Mortreux, Serge; Le Gall, Patrik; Chiantella, Claude; Fiandrino, Annie; Bernard, Ismael; Pouvreau, Stephane; Roque D'Orbcastel, Emmanuelle.
The Thau lagoon, located at the South of France, provides 10% of the French pacific oyster Crassostrea gigas production. Despite this intensive shellfish production, the larval recruitment of this species within the Thau lagoon is still misunderstood and spat collection remains highly variable; as a consequence, shellfish farmers rely mostly on hatchery”s spat. The present study aimed to describe reproduction features of C. gigas within the Mediterranean, as well as to explore spawning triggers of this species. To achieve this goal, the reproduction cycle from gametogenesis to spawning was followed during two years in several locations within the Mediterranean Thau lagoon. The spawning behavior of C. gigas within the Thau lagoon appeared to be slightly...
Tipo: Text
Palavras-chave: Mollusc physiology; Spawning triggers; Oysters.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00369/48032/48118.pdf

New insights into the reproductive cycle of two Great Scallop populations in Brittany (France) using a DEB modelling approach
Provedor de dados: 5
Autores: 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

Pearl Oysters Pinctada margaritifera grazing on natural plankton in Ahe atoll lagoon (Tuamotu archipelago, French Polynesia)
Provedor de dados: 5
Autores: Fournier, Jonathan; Dupuy, Celie; Bouvy, Marc; Couraudon-reale, Marine; Charpy, Loic; Pouvreau, Stephane; Le Moullac, Gilles; Le Pennec, Marie-annick; Cochard, Jean-claude.
In atoll lagoons of French Polynesia, growth and reproduction of pearl oysters are mainly driven by plankton concentration. However, the actual diet of black-lip pearl oysters P. margaritifera in these lagoons is poorly known. To fill this gap, we used the flow through chamber method to measure clearance rates of P. margaritifera in Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia). We found : (i) that pearl oysters cleared plankton at a rate that was positively related to plankton biovolume, (ii) that nanoflagellates were the main source of carbon for the pearl oysters, (iii) that the quantity and origin of carbon filtrated by pearl oysters was highly dependent on the concentration and composition of plankton. These results provide essential...
Tipo: Text
Palavras-chave: Pinctada margaritifera; Clearance rates; French Polynesia; Phytoplankton; Protists.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00078/18888/16599.pdf

Genetically based resistance to summer mortality in the Pacific oyster (Crassostrea gigas) and its relationship with physiological, immunological characteristics and infection processes
Provedor de dados: 5
Autores: Samain, Jean-francois; Degremont, Lionel; Soletchnik, Patrick; Haure, Joel; Bedier, Edouard; Ropert, Michel; Moal, Jeanne; Huvet, Arnaud; Bacca, Helene; Van Wormhoudt, A; Delaporte, Maryse; Costil, K; Pouvreau, Stephane; Lambert, Christian; Boulo, Viviane; Soudant, Philippe; Nicolas, Jean-louis; Leroux, Frederique; Renault, Tristan; Gagnaire, Beatrice; Geret, Florence; Boutet, Isabelle; Burgeot, Thierry; Boudry, Pierre.
Summer mortality of Pacific oysters is known in several countries. However no specific pathogen has been systematically associated with this phenomenon. A complex combination of environmental and biological parameters has been suggested as the cause and is now starting to be identified. A high genetic basis was found for survival in oysters when a first generation (G1) was tested in three sites during summer. This paper presents a synthesis on physiological characteristics of two selected groups ('R' and 'S', from families selected for resistance and susceptibility to summer mortality respectively), of the second and third generations. R and S showed improvement or reduction of survival compared with the control in both field and laboratory trials...
Tipo: Text
Palavras-chave: ROS; Temperature; Stress; Hemocytes; Reproduction; Genetic selection; Resistant oyster; Crassostrea gigas; Pacific Oyster; Summer mortality.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2809.pdf

Biological characteristics of sperm in European flat oyster (     Ostrea edulis     )
Provedor de dados: 5
Autores: Suquet, Marc; Pouvreau, Stephane; Queau, Isabelle; Boulais, Myrina; Le Grand, Jacqueline; Ratiskol, Dominique; Cosson, Jacky.
n brooding mollusc species that incubate larvae before their release in seawater, the biology of gametes remains poorly explored. The present study describes some biological characteristics of sperm of the European flat oyster, a native species that has been over-exploited in the past and is nowadays classified as an endangered species in Europe. Flat oysters were collected by divers in the Rade de Brest (Finistère, France), during its natural reproduction period. Gonadal pH is acidic (6.31 ± 0.10). Spermatozoa are clustered in spermatozeugmata, an acellular structure in which the sperm heads are embedded. After their transfer in seawater, spermatozeugmata have a mean diameter of 64 ± 3 μm and they release free spermatozoa for a mean duration of...
Tipo: Text
Palavras-chave: Oyster; Ostrea edulis; Brooding species; Sperm; Spermatozeugmata; Endangered species.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00454/56539/58245.pdf

Gametogenic cycle and reproductive effort of the tropical blacklip pearl oyster, Pinctada margaritifera (Bivalvia : Pteriidae), cultivated in Takapoto atoll (French Polynesia)
Provedor de dados: 5
Autores: Pouvreau, Stephane; Gangnery, Aline; Tiapari, Jerome; Lagarde, Franck; Garnier, Matthieu; Bodoy, Alain.
The gametogenic cycle and the reproductive effort of the blacklip pearl oyster, Pinctada margaritifera, cultivated in Takapoto lagoon were studied for a 1-year period (March 1997-April 1998) by bimonthly observations of gonadal sections, dry tissue weights and gonadal index in a population of pearl oyster composed of three age-groups. pearl oysters attained sexual maturity in the end of their first year (height approximate to 40 mm), implying that P. margaritifera is a late-maturing species in comparison with other Pteriidae. This species was also confirmed to be a marked protandrous successive hermaphrodite in culture, with 100 % of males at first maturity and 75 % in older pearl oyster (height &gt; 120 mm). The general pattern of gametogenic activity,...
Tipo: Text
Palavras-chave: French Polynesia; Reproductive effort; Reproductive cycle; Tropical aquaculture; Gametogenesis; Blacklip pearl oyster; Polynésie française; Effort de reproduction; Cycle de reproduction; Aquaculture tropicale; Gamétogenèse; Huître perlière.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-1391.pdf

Modelling spatio-temporal variability of Mytilus edulis (L.) growth by forcing a dynamic energy budget model with satellite-derived environmental data
Provedor de dados: 5
Autores: 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

Influence of food supply on the delta C-13 signature of mollusc shells: implications for palaeoenvironmental reconstitutions
Provedor de dados: 5
Autores: Lartaud, Franck; Emmanuel, Laurent; De Rafelis, Marc; Pouvreau, Stephane; Renard, Maurice.
Compared to oxygen isotopes, the carbon isotope composition of biogenic carbonates is less commonly used as proxy for palaeoenvironmental reconstructions because shell delta C-13 is derived from both dissolved inorganic (seawater) and organic carbon sources (food), and interactions between these two pools make it difficult to unambiguously identify any independent effect of either. The main purpose of this study was to demonstrate any direct impact of variable food supply on bivalve shell delta C-13 signatures, using low/high rations of a C-13-light mixed algal diet fed to 14-month-old (adult) cultured Japanese Crassostrea gigas under otherwise essentially identical in vitro conditions during 3 summer months (May, June and July 2003, seawater temperature...
Tipo: Text
Ano: 2010
URL: http://archimer.ifremer.fr/doc/2010/publication-7435.pdf

Application of a bioenergetic growth model to larvae of the pearl oyster Pinctada margaritifera L.
Provedor de dados: 5
Autores: Thomas, Yoann; Garen, Pierre; Pouvreau, Stephane.
We applied, for the first time, a dynamic energy budget (DEB) growth model to the larval phase in the pearl oyster Pinctada margaritifera var. cumingii (Linnaeus, 1758) to evaluate the impact of spatio-temporal variation in the atoll lagoon environment on its capacity for development. The specific parameters of the model, which represent ingestion, temperature effect and the relationship between length and biovolume of the larvae, were determined from experiments or taken from the literature. The interpretation of the values of these parameters allowed us to identify the underlying adaptive character trait: P. margaritifera larvae have a good capacity to exploit low food concentrations and a narrow range of thermal tolerance restricted to hydrobiological...
Tipo: Text
Palavras-chave: Growth Model; Dynamic Energy Budget; Larva; Pinctada Margaritifera; Atoll Lagoon.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00048/15919/13346.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport scientifique annuel du réseau national Velyger, convention DPMA-Ifremer 2016
Provedor de dados: 5
Autores: Pouvreau, Stephane.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 60 à 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage. Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une quinzaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (2003, 2006, 2008, 2012, 2014). A Marennes-Oléron, cette variabilité existe, mais s’avère beaucoup...
Tipo: Text
Palavras-chave: Huître creuse; Naissain; Cycle de reproduction; Captage; Recrutement; Changement climatique; Larves; Pacific oyster; Spat; Recruitment; Seed collecting; Larvae; Reproductive cycle; Climate change.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00433/54427/55776.pdf

Ovarian and sperm regulatory peptides regulate ovulation in the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Bernay, Benoît; Baudy-floc'H, Michele; Zanuttini, Bruno; Zatylny, Céline; Pouvreau, Stephane; Henry, Joël.
For more than six decades, several studies have shown that genital products to entering the mantle cavity via the incurrent siphon, initiate in oyster, strong and rhythmic contractions of the adductor muscle (AM). In order to characterize the regulatory peptides capable of triggering AM contractions, we focused on the identification of putative myotropic peptides from genital products. Two experimental approaches were developed. The first one, based on a mass spectrometry screening of the male genital products, led to the identification of the tetrapeptide APGWamide. This neuropeptide was also detected in the seminal secretions of the cephalopod Sepia officinalis. In this species, APGWamide is directly involved in the oocyte transport. In Crassostrea, in...
Tipo: Text
Palavras-chave: Mass spectrometry; Myotropin; APGWamide; Egg laying; Molluscan.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1697.pdf

L’huître creuse, sentinelle de l’état de santé des écosystèmes côtiers exploités du littoral français. Rapport annuel ECOSCOPA 2016
Provedor de dados: 5
Autores: 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...
Tipo: Text
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00433/54425/55774.pdf

Oyster vasa-like gene as a marker of the germline cell development in Crassostrea gigas
Provedor de dados: 5
Autores: Fabioux, Caroline; Huvet, Arnaud; Lelong, C; Robert, Rene; Pouvreau, Stephane; Daniel, Jean-yves; Mingant, Christian; Le Pennec, M.
The oyster vasa-like gene was previously demonstrated to be specifically expressed in germline cells of adult oysters Crassostrea gigas. In the present study, this gene was used as a molecular marker to establish the developmental pattern of germline cells during oyster ontogenesis. using whole-mount in situ hybridization and real-time PCR. The Oyvlg transcripts appeared to be localized to the vegetal pole of unfertilized oocytes and maternally transmitted to embryos. At early development, these maternal transcripts were observed to segregate into a single blastomere, from the CD macromere of 2-cell stage to the 4d mesentoblast of blastula. From late blastula stage, the mesentoblast divided into two cell clumps that migrated to both sides of the larvae...
Tipo: Text
Palavras-chave: Primordial germ cells; Oyster vasa like gene; Germline; Development; Crassostrea gigas.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-648.pdf

Impact of Brown Ring Disease on the energy budget of the Manila clam Ruditapes philippinarum
Provedor de dados: 5
Autores: Flye Sainte Marie, Jonathan; Pouvreau, Stephane; Paillard, Christine; Jean, Fred.
Brown Ring Disease (BRD) is a bacterial disease caused by the pathogen, Vibrio tapetis. The disease induces formation of a brown deposit on inner shell of the Manila clam, Ruditapes philippinarum. Development of this disease is correlated with a decrease in the condition index of infected clams. Experiments were conduced in order to assess the effect of the development of BRD on two parameters affecting the energy balance of the clams: the clearance and the respiration rates. Experiments were performed in a physiological measurement system that allowed simultaneous measures of clearance and respiration rates. During both acclimation and measurements clams were fed with cultured T-iso and temperature was close to seasonal field temperature (10 degrees C....
Tipo: Text
Palavras-chave: Ruditapes philippinarum; Respiration rate; Filtration; Energy budget; Clearance rate; Brown Ring Disease.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3013.pdf

Characterisation of physiological and immunological differences between Pacific oysters (Crassostrea gigas) genetically selected for high or low survival to summer mortalities and fed different rations under controlled conditions
Provedor de dados: 5
Autores: Delaporte, Maryse; Soudant, P; Lambert, C; Jegaden, M; Moal, Jeanne; Pouvreau, Stephane; Degremont, Lionel; Boudry, Pierre; Samain, Jean-francois.
Within the framework of a national scientific program named "MORtalites ESTivales de l'huitre creuse Crassostrea gigas" (MOREST), a family-based experiment was developed to study the genetic basis of resistance to summer mortality in the Pacific oyster, Crassostrea gigas. As part of the MOREST project, the second generation of three resistant families and two susceptible families were chosen and pooled into two respective groups: "R" and "S". These two groups of oysters were conditioned for 6 months on two food levels (4% and 12% of oyster soft-tissue dry weight in algal dry weight per day) with a temperature gradient that mimicked the Marennes-Oleron natural cycle during the oyster reproductive period. Oyster mortality remained low for the first two...
Tipo: Text
Palavras-chave: Summer mortality; Reproduction; Reactive oxygen species ROS; Hemocyte parameters; Genetic selection; Crassostrea gigas.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3578.pdf

Modeling reproductive traits of an invasive bivalve species under contrasting climate scenarios from 1960 to 2100
Provedor de dados: 5
Autores: 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

Impact of food availability on energy storage and defense related hemocyte parameters of the Pacific oyster Crassostrea gigas during an experimental reproductive cycle
Provedor de dados: 5
Autores: Delaporte, Maryse; Soudant, P; Lambert, C; Moal, Jeanne; Pouvreau, Stephane; Samain, Jean-francois.
The aim of this study was to test the effect of food quantity on energy storage and defense capacities of oysters during a reproductive cycle. One-year-old Crassostrea gigas oysters were fed two different dietary rations (4% and 12% of oyster dry weight in algal dry weight per day) in controlled experimental conditions over an annual cycle. Oyster dry weights, carbohydrate and lipid contents, energetic adenylate charge, and hemocyte parameters of oysters were significantly affected by reproductive processes related to seasonal temperature variation and, to a lesser extent, by the dietary rations. Energy parameters decreased during gametogenesis as gonads developed then increased during the gonad resorption phase. The additional energy provided to oysters...
Tipo: Text
Palavras-chave: Reactive oxygen species production; Reproduction; Phagocytosis; Hemocyte parameters; Energy storage; Crassostrea gigas.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1549.pdf

Influence of plankton concentration on gametogenesis and spawning of the black lip pearl oyster Pinctada margaritifera in Ahe atoll lagoon (Tuamotu archipelago, French polynesia)
Provedor de dados: 5
Autores: Fournier, Jonathan; Levesque, Emmanuelle; Pouvreau, Stephane; Le Pennec, Marcel; Le Moullac, Gilles.
Pearl culture industry represents one of the dominant business sector of French Polynesia. However, it still entirely relies on unpredictable spat collection success. Our aim was to assess the influence of natural plankton concentration fluctuations on maturation and spawning of the black lip pearl oyster Pinctada margaritifera, during a 4 months survey conducted in Ahe atoll lagoon. Plankton concentration was assessed by chlorophyll a extraction and by microscope counts while gonadic index, gonado-visceral dry weights and histology were used to measure pearl oysters reproduction activity. We found that (i) plankton concentration fluctuations were mainly related to wind regime, (ii) gametogenesis rate was mainly related to plankton concentration, (iii)...
Tipo: Text
Palavras-chave: Pearl Oyster; Gametogenesis; Spawning; Phytoplankton; French Polynesia.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00101/21201/19697.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2014
Provedor de dados: 5
Autores: Pouvreau, Stephane; Petton, Sebastien; Queau, Isabelle; Haurie, Axel; Le Souchu, Pierrick; Alunno-bruscia, Marianne; Palvadeau, Hubert; Auby, Isabelle; Maurer, Daniele; D'Amico, Florence; Passoni, Sarah; Barbier, Claire; Tournaire, Marie-pierre; Rigouin, Loic; Rumebe, Myriam; Fleury, Elodie; Fouillaron, Pierre; Bouget, Jean-francois; Pepin, Jean-francois; Robert, Stephane; Grizon, James; Seugnet, Jean-luc; Chabirand, Jean-michel; Le Moine, Olivier; Guesdon, Stephane; Lagarde, Franck; Mortreux, Serge; Le Gall, Patrik; Messiaen, Gregory; Roque D'Orbcastel, Emmanuelle; Quemener, Loic; Repecaud, Michel; Mille, Dominique; Geay, Amelie; Bouquet, Anne-lise.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage. Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple les années 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (les années 2003, 2006, 2008, 2012, 2013). A Marennes-Oléron, cette variabilité existe, mais...
Tipo: Text
Palavras-chave: Huître creuse; Naissain; Recrutement; Captage; Larves; Cycle de reproduction; Changement climatique; Pacific oyster; Spat; Recruitment; Spat collecting; Larvae; Reproductive cycle; Climate change.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00279/38990/37561.pdf

Transcriptional regulation of pyruvate kinase and phosphoenolpyruvate carboxykinase in the adductor muscle of the oyster Crassostrea gigas during prolonged hypoxia
Provedor de dados: 5
Autores: Le Moullac, Gilles; Bacca, Helene; Huvet, Arnaud; Moal, Jeanne; Pouvreau, Stephane; Van Wormhoudt, A.
The response of Crassostrea gigas to prolonged hypoxia was investigated for the first time by analyzing the metabolic branch point formed by pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK). PK and PEPCK cDNAs were cloned and sequenced. The main functional domains of the PK sequence, such as the binding sites for ADP/ATP and phosphoenolpyruvate (PEP), were identified whereas the PEPCK sequence showed the specific domain to bind PEP in addition to the kinase-1 and kinase-2 motifs to bind guanosine triphosphate (GTP) and Mg2+, specific for all PEPCKs. A C-terminal extension was detected for the first time in eukaryota PK. Separation of mitochondrial and cytosolic fraction showed that more than 92% of the PEPCK enzyme activity was cytosolic...
Tipo: Text
Palavras-chave: Succinate alanine carboxykinase phosphoenolpyruvate pyruvate kinase hypoxia Oyster.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2683.pdf

Latitudinal drivers of oyster mortality: deciphering host, pathogen and environmental risk factors
Provedor de dados: 5
Autores: 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
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00627/73915/73251.pdf

Genetic variation and trade-offs for reproduction ans survival in the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Boudry, Pierre; Degremont, Lionel; Bedier, Edouard; Pouvreau, Stephane; Normand, Julien; Ernande, Bruno.
To date, the most significant method to genetically reduce reproductive effort in the Pacific oyster (Crassostrea gigas) has been through the production of triploids, especially since the development of tetraploid lines allowing the breeding of 'natural' triploids. Gametogenesis of triploid oysters is strongly reduced compared with diploids, although they are not fully sterile and can produce viable gametes and some progenies when crossed with diploids. Reduced reproductive allocation and higher heterozygocity are commonly proposed as the main reasons why triploids often present superior yield compared with diploids. Temperature and food availability are known to favour gametogenesis in triploids, but the existence of genetic variation for this trait...
Tipo: Text
Palavras-chave: Selective breeding; Reproduction; Genetic variation; Crassostrea gigas; Pacific oyster; Genetic.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/acte-3445.pdf

Observatoire national du cycle de vie de l’huître creuse en France. Rapport annuel ECOSCOPA 2017
Provedor de dados: 5
Autores: Pouvreau, Stephane; Fleury, Elodie; Petton, Sebastien; Corporeau, Charlotte; Lapegue, Sylvie.
Occupant une place de premier ordre dans les paysages côtiers français, 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, installée en France depuis plus de 50 ans, joue aussi un rôle essentiel sur le plan écologique dans les écosystèmes qui l’abritent. Pourtant, depuis plusieurs années, cette filière 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 (sous sa forme µVar) affectant les naissains et des mortalités d’adultes associées à la bactérie Vibrio aestuarianus. Ces épisodes de...
Tipo: Text
Palavras-chave: Huître creuse; Physiologie; Génétique; Ecologie; Réseau National.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00449/56030/57556.pdf

Temperature and photoperiod drive Crassostrea gigas reproductive internal clock
Provedor de dados: 5
Autores: Fabioux, Caroline; Huvet, Arnaud; Le Souchu, Pierrick; Le Pennec, Marcel; Pouvreau, Stephane.
This study examined the gametogenic cycle of Crassostrea gigas in controlled conditions over one year, with a focus on the initiation of gametogenesis. This work analysed also the role of temperature and photoperiod in the regulation of oyster reproduction. Broodstock were maintained in natural (NC), accelerated (AC) and perpetual winter (WC) conditions of temperature and photoperiod, with feeding ad libitum. Qualitative and quantitative analyses of the reproductive pattern were performed using biometric measurement approach, sex ratio determination, histology and a gonad filling index. Each experimental treatment led to different strategies for growth and resource allocation. The gametogenic cycle, appeared entirely modulated, accelerated or delayed, by...
Tipo: Text
Palavras-chave: Temperature; Regulation; Gonad filling index; Gonial mitosis; Reproduction; Oyster.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-826.pdf

Etude de faisabilité d’opérations de ‘repeuplement orienté’ dans deux sites français de captage de l’huître creuse (Crassostrea gigas)
Provedor de dados: 5
Autores: Bernard, Ismael; Lapegue, Sylvie; Dumas, Franck; Talarmain, Eric; Cornette, Florence; Degremont, Lionel; Chavanne, Herve; Pouvreau, Stephane; Auby, Isabelle; Maurer, Daniele; Plus, Martin; Le Moine, Olivier; Boudry, Pierre.
La forte augmentation des mortalités de juvéniles d’huître creuse depuis 2008 a relancé la problématique de l’approvisionnement en naissains de l’ostréiculture française. Dans ce contexte, cette étude a pour objectif d’étudier la faisabilité d’opérations de repeuplement en huîtres génétiquement plus résistantes, afin d’améliorer les performances de survie du naissain capté dans le milieu naturel. Cette étude s’est ainsi focalisée sur les deux bassins naisseurs historiques, Marennes-Oléron et Arcachon. Nous avons donc cherché à établir (1) une hiérarchie des bancs en fonction de l’expulsion de larves d’huître dans le bassin d’Arcachon, (2) une cartographie des liens en termes de connectivité entre les bancs des pertuis charentais et (3) la faisabilité du...
Tipo: Text
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00083/19410/17013.pdf

Ecophysiological and metabolic adaptations to sulphide exposure of the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Le Moullac, Gilles; Cheize, Marie; Gastineau, Olivier; Daniel, Jean-yves; Le Coz, Jean-rene; Huvet, Arnaud; Moal, Jeanne; Pouvreau, Stephane; Van Wormhoudt, A; Samain, Jean-francois.
The purpose of this study is to examine the response of the oyster Crassostrea gigas to sulphide at different biological scales. A first experiment was designed to measure for 20 h the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of sulphide (0, 3, 6, 12, 20, and 40 mu M). The second experiment was carried out to evaluate the metabolic adaptations to chronic sulphide exposure for 10 days by measuring PK and PEPCK enzyme activities, succinate and alanine content, the adenylate energy charge (AEC), and the activity of the electron transport system (ETS)in whole oysters at above 20 mu M. PK and PEPCK mRNAs and enzyme activities have been measured in adductor muscle. When exposed to sulphide above 20 mu M, CR...
Tipo: Text
Palavras-chave: ATP; AEC; Electron transport system; Succcinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Oxygen consumption; Clearance rate; Crassostrea gigas; Sulphide; Oyster.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3924.pdf

Programme général de recherche sur la nacre. Écophysiologie de l'huître perlière, approche des relations entre  la croissance de l'huître Pinctada  margaritifera  et le milieu dans le lagon de Takapoto
Provedor de dados: 5
Autores: Buestel, Dominique; Pouvreau, Stephane; Tiapari, Jerome; Bougrier, Serge; Chabirand, Jean-michel; Geairon, Philippe; Fougerouse, A.
A study of pearl oysters Pinctada margaritifera growth and mortality was done on a monthly basis between June 1990 and September 1991 in Takapoto atoll (Tuamotu archipelago). Meanwhile, sampling parameters representative of bivalves food showed a remarquable spatial stability whithin the lagoon. The amplitude of temporal variability varied in the order of some days. Carrying capacity appears low : energetic content of particulate material in waters is about 2 joules/liter, ten times lower than in temperate areas. On the opposite, seasonal effect is reduced and particulate food is always available. Oysters rearing conditions were appropriate during the studied period with a low mortality rate and a regular growth in size (from 97 mm to 136 mm). Pearls...
Tipo: Text
Palavras-chave: Atoll; Pearl oyster; Carrying capacity; Growth; Pinctada margaritifera; Atoll; Huître perlière; Capacité Trophique; Croissance; Pinctada margaritifera.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/rapport-1642.pdf

Qualification zoo-sanitaire du naissain de captage 2013 de l'huître creuse Crassostrea gigas (QUALIF) - Détection précoce des maladies en épreuve thermique de laboratoire
Provedor de dados: 5
Autores: Petton, Bruno; Riobe, Marion; Koechlin, Hugo; Queau, Isabelle; Mingant, Christian; Ratiskol, Dominique; Le Grand, Jacqueline; Petton, Sebastien; Thomas, Yoann; Alunno-bruscia, Marianne; Pouvreau, Stephane; Pernet, Fabrice; Maurer, Daniele; D'Amico, Florence; Lagarde, Franck; Mortreux, Serge; Roque D'Orbcastel, Emmanuelle; Mille, Dominique; Geay, A.; Bouquet, A.-l.; Cochet, Helene.
Depuis 2008, des mortalités massives d’huîtres creuses âgées de moins d’un an sont relevées sur le littoral français dès que la température de l’eau de mer atteint le seuil de 16°C. Ces mortalités de naissains sont associées à la détection du virus OsHV-1 μVar. Des travaux de qualification zoo-sanitaire menés depuis 2010 ont montré qu’un lot de naissains issus du captage naturel sur deux était infecté par le virus bien avant l’apparition des mortalités dans le milieu naturel, mais qu’a contrario les naissains d’écloserie expertisés présentaient un moindre risque de contamination. Dans le contexte de crise sanitaire chronique, l’objectif de notre étude était d’ obtenir une information qualitative relative au statut zoo-sanitaire OsHV -1 μ V ar des...
Tipo: Text
Palavras-chave: Huitre creuse; OsHV - 1μVar; Epreuve thermique.; Maladie; Naissain; Pacific oyster; Spat; Disease; Thermal challenge; OsHV-1 μVar.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00276/38682/37180.pdf

Effect of phytoplankton and temperature on the reproduction of the Pacific oyster Crassostrea gigas: investigation through DEB theory
Provedor de dados: 5
Autores: Bernard, Ismael; De Kermoysan, Goulwen; Pouvreau, Stephane.
DEB theory can be used to obtain a detailed description of energy allocation in organisms and the control of this allocation by temperature and food concentration. In this study, we modified the model of Bourlès et al. (2009) developed for the Pacific oyster, Crassostrea gigas, to improve the description of reproductive effort. The model was amended in two ways: a new set of parameters was incorporated and a full description of gonad construction in spring was added, with a new state variable. The application of this model to a dataset for oyster growth measured in four bays over two years showed that this model better described reproductive effort, without modifying overall growth dynamics. We then explored the reproductive responses of oysters to their...
Tipo: Text
Palavras-chave: DEB model; Crassostrea gigas; Gametogenesis; Reproductive effort; Spawning date; Functional response.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00059/17047/14606.pdf

Particulate matter in Takapoto lagoon waters: potential food for cultivated pearl oysters
Provedor de dados: 5
Autores: Buestel, Dominique; Pouvreau, Stephane.
Results of research concerning the food of the pearl oyster Pinctada mai margaritifera are presented, by taking Takapoto atoll (Tuamotu archipelago, French Polynesia) as a study site. Monthly sampling of several parameters representative of bivalve environment and food (water temperature, salinity, mineral and organic matter, proteins, lipids and carbohydrates, chlorophyll a and phaeopigments) confirm and increase knowledge of the Takapoto lagoon hydrobiology. The variability of these parameters was analysed. Takapoto lagoon showed a remarkable spatial stability. Temporal variations showed a low seasonal trend. Local meteorology (wind, precipitation) had an influence on short-term variability (especially for mineral matter). Night and day rhythm also...
Tipo: Text
Palavras-chave: Pinctada margaritifera; Matière en suspension; Capacité trophique; Huı̂tre perlière; Atoll; Pinctada margaritifera; Suspended matter; Carrying capacity; Pearl oyster; Atoll.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00000/10529/7078.pdf

The oyster vasa-like gene: a specific marker of the germline in Crassostrea gigas
Provedor de dados: 5
Autores: Fabioux, Caroline; Pouvreau, Stephane; Leroux, Frederique; Huvet, Arnaud.
The vasa gene is,a key determinant for germline formation in eukaryotes. This gene, highly conserved through evolution, encodes a RNA helicase protein member of the DEAD-box family. To understand the germline formation in oyster, we report here the isolation and the characterization of a vasa orthologue in Crassostrea gigas (Oyvlg). OyVLG contained the eight consensus domains of the DEAD-box including those providing RNA unwinding activity. The expression pattern of Oyvlg was examined in adult oyster tissues at different reproductive stages. Its expression was restricted to germline cells both in males and females, including germinal stem cells and auxiliary cells. The expression of Oyvlg, strongest in early germ cells, decreased as the maturation...
Tipo: Text
Palavras-chave: RNA helicase; DEAD box; Vasa; Germline; Gametogenesis; Oyster.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-646.pdf

Etude de la fécondité de l’huître creuse dans le bassin d’Arcachon en 2013 en lien avec la qualité de l’eau. Compte-rendu final du programme FeLiBA
Provedor de dados: 5
Autores: Bernard, Ismael; Allain, Gwenhael; Auby, Isabelle; Plus, Martin; Drean, Tugdual; Gasmi, Sonia; David, Valérie; Pouvreau, Stephane; Maurer, Daniele.
De 2009 à 2011, le captage à Arcachon fut particulièrement mauvais. Des pontes tardives associées à de faibles quantités de larves “petites” indiquaient un problème probablement au niveau de la maturation ou de la ponte. Le programme FéLiBA consiste en un zoom, pour l’année 2013, sur la Fécondité des huîtres creuses en Lien avec la qualité de l’eau du Bassin d’Arcachon. Ce programme s’est traduit par différentes actions de terrain. Tout d’abord, la maturation des huîtres issues du captage d’Arcachon ou de Marennes-Oléron a été suivie à Arcachon (site du Tès) et comparée avec celle de la Rade de Brest (pointe du Château) au cours de l’année 2013. Puis, un bilan de la maturation des huîtres sauvages d’Arcachon a été établi fin juin 2013. La ponte a également...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00179/29002/27428.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2013
Provedor de dados: 5
Autores: Pouvreau, Stephane; Petton, Sebastien; Queau, Isabelle; Bellec, Gwenael; Talarmain, Eric; Le Souchu, Pierrick; Alunno-bruscia, Marianne; Auby, Isabelle; Maurer, Daniele; D'Amico, Florence; Passoni, Sarah; Barbier, Claire; Tournaire, Marie-pierre; Rigouin, Loic; Rumebe, Myriam; Fleury, Elodie; Langlade, Aime; Bouget, Jean-francois; Collin, Karine; Fortune, Mireille; Palvadeau, Hubert; Bedier, Edouard; Robert, Stephane; Pepin, Jean-francois; Grizon, James; Seugnet, Jean-luc; Chabirand, Jean-michel; Le Moine, Olivier; Guesdon, Stephane; Lagarde, Franck; Mortreux, Serge; Le Gall, Patrik; Messiaen, Gregory; Roque D'Orbcastel, Emmanuelle; Quemener, Loic; Repecaud, Michel; Bucas, Karenn; Barbot, Stephane; Guillemot, Anne; Nonnotte, Lidwine; Duros, Wenceslas; Bonnat, Armel; Tarot, Stephane; Mille, Dominique; Geay, Amelie; Bouquet, Anne-lise.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage.  Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple les années 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (les années 2003, 2006, 2008, 2012, 2013). A Marennes-Oléron, cette variabilité existe, mais...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00200/31091/29499.pdf

Défi MOREST - Mortalités estivales de l'huître creuse Crassostrea gigas. Caractérisation des facteurs de risques associés aux mortalités estivales - Synthèse du thème 6 - Le risque température. (La Rochelle 14- 15 mars 2006)
Provedor de dados: 5
Autores: Lambert, C.; Moal, J.; Pouvreau, Stephane; Le Moullac, Gilles; Samain, Jean-francois.
Les mortalités apparaissent toujours très rapidement après le passage de la température de l'eau à 19°C. II a bien été montré que ce n'était pas la valeur absolue de la température qui était associée à la mortalité, puisque des années très chaudes comme 2003, peu de mortalités étaient enregistrées. II s'agit plutôt d'un seuil à partir duquel le risque devient réel. La température affecte tous les processus de la physiologie et c'est un facteur clef de la distribution géographique des espèces. Les espèces se maintiennent dans les conditions environnementales qui ont permis leur adaptation. Les mortalités traduisent donc une rupture de l'adaptation ou une modification brutale de l'environnement qui peut affecter les équilibres qui se sont installés entre...
Tipo: Text
Ano: 2006
URL: http://archimer.ifremer.fr/doc/00304/41537/40745.pdf

Observatoire national du cycle de vie de l’huître creuse en France. Rapport annuel ECOSCOPA 2019
Provedor de dados: 5
Autores: Fleury, Elodie; Petton, Sebastien; Corporeau, Charlotte; Benabdelmouna, Abdellah; Pouvreau, Stephane.
Occupant une place de premier ordre dans les paysages côtiers français, l’ostréiculture est le premier contributeur de la filière aquacole française avec une production estimée à 85000 tonnes ces dernières années. Pourtant, depuis 2008, cette espèce est affectée par des épisodes de mortalités massives et récurrentes déclenchées par la présence d'agents infectieux viraux (de type Herpes virus OsHV-1 μVar) en conjonction avec des facteurs environnementaux (i.e. élévation de la température). Cette infection virale induit une altération des défenses antimicrobiennes ainsi qu'une déstabilisation de son microbiote. Ce processus conduit à une infection secondaire par des bactéries opportunistes potentiellement pathogènes qui se multiplient rapidement entrainant...
Tipo: Text
Palavras-chave: Huître creuse; Physiologie; Cytogénétique; Écologie; Réseau National.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00687/79902/82833.pdf

Recherche de gisements de captage naturel de Crassostrea gigas en lagune de Thau.Répartition spatiotemporelle du naissain, aspects culturaux et économiques.
Provedor de dados: 5
Autores: Lagarde, Franck; Perignon, Adeline; Gervasoni, Erika; Mortreux, Serge; Meddah, Slem; Leurion, Axel; Le Gall, Patrik; Guillou, Jean-louis; Boj, Marie; Fuhrmann, Marine; Richard, Marion; Ubertini, Martin; Fiandrino, Annie; Roque D'Orbcastel, Emmanuelle; Pouvreau, Stephane.
Le travail est axé sur la volonté de la filière conchylicole méditerranéenne pour s'approvisionner en naissains d'huîtres creuses sauvages d’origine lagunaire. L'observatoire du captage naturel, mis en place entre 2012 et 2014, a permis de découvrir des gisements de naissains collectés naturellement dans la lagune de Thau selon un protocole défini à l’échelle expérimentale. Bien que très hétérogènes spatialement et temporellement, les densités de naissains sur les collecteurs révèlent des catégories de captage allant de "moyen i. e. 20 à 200 naissains par coupelle" à "excellent i. e. 200 à 2000 naissains par coupelle " sur certaines stations expérimentales. Les expériences de captage naturel à échelle semi-industrielle (avec filière de coupelles en lagune)...
Tipo: Text
Palavras-chave: Captage naturel; Crassostrea gigas; Recrutement; Conchyliculture méditerranéenne; Lagune.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00260/37103/35632.pdf

Modelling the influence of environmental factors on the physiological status of the Pacific oyster Crassostrea gigas in an estuarine embayment; The Baie des Veys (France)
Provedor de dados: 5
Autores: 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

Nutrition and reproduction are key parameters in the interaction process leading to Crassostrea gigas oyster summer mortality in France
Provedor de dados: 5
Autores: Samain, Jean-francois; Degremont, Lionel; Soletchnik, Patrick; Ropert, Michel; Bedier, Edouard; Mazurie, Joseph; Mazurie, Joseph; Martin, Jean-louis; Moal, Jeanne; Mathieu, Michel; Pouvreau, Stephane; Lambert, Christophe; Escoubas, Jean-michel; Nicolas, Jean-louis; Le Roux, Frédérique; Renault, Tristan; Burgeot, Thierry; Bacher, Cedric; Boudry, Pierre.
Complex interactions between oyster, environment and pathogens were observed during the MOREST (2001-2005) project on summer mortality events of Crassostrea gigas oysters in France. The talk will show how nutrition level increasing reproductive intensity generates a risk for pathogen infection under synergistic effect of temperature and stress. Moreover, a genetic component is associated to specific reproductive performances and spawning behaviour. To better understand origin of such resistance or susceptibility to summer mortality, other characteristics as stress susceptibility, energy management and hemocyte activities of oysters from the two phenotypes were compared. This first comparison suggests interactions between stress, reproduction and defence...
Tipo: Text
Palavras-chave: Genetic; Pathologie; Mortality; Crassostrea gigas; Pacific oyster; Reproduction; Nutrition; Physilogy.
Ano: 2006
URL: https://archimer.ifremer.fr/doc/2006/acte-3467.pdf

Les métiers du filet fixe en France (Régions 1, 2 et 3)
Provedor de dados: 5
Autores: 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
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00049/16036/13511.pdf

Conception et réalisation de bancs automatisés pour les mesures écophysiologiques des mollusques filtreurs en condition contrôlée à La Station Expérimentale d'Argenton
Provedor de dados: 5
Autores: Fagon, N.; Le Souchu, Pierrick; Lefebvre, Sebastien; Pouvreau, Stephane.
Force est de constater que, malgré un intérêt croissant depuis les 20 dernières années en matière d'écophysiologie des mollusques, il n'existe, à notre connaissance, aucun système réellement adapté à la mesure en continu et de façon concomitante des principales fonctions écophysiologies des mollusques filtreurs (notamment consommation et filtration). Faisant suite à la réalisation d'un cahier des charges et d'une version préliminaire d'un système, le but du présent projet est de doter la Station Expérimentale d'Argenton (entité expérimentale de l'UMR « Physiologie et Ecophysiologie des Mollusques Marins) de deux systèmes automatisés et opérationnels de mesures de l'écophysiologie des mollusques filtreurs. Après un bref rappel des principes de mesures des...
Tipo: Text
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00306/41769/40982.pdf

Observer, Analyser et Gérer la variabilité de la reproduction et du recrutement de l’huître creuse en France : Le Réseau Velyger. Rapport annuel 2015
Provedor de dados: 5
Autores: Pouvreau, Stephane.
La conchyliculture, et principalement l’élevage de l’huître creuse, Crassostrea gigas, constitue la principale activité aquacole française. Cette activité repose, en grande partie, sur le recrutement naturel de l’espèce qui assure 60 à 70% des besoins en jeunes huîtres (naissain) : cette activité de collecte s’appelle le captage.  Les deux principaux centres de captage en France sont les bassins d’Arcachon et de Marennes-Oléron. Or, depuis une dizaine d'années, sur le bassin d'Arcachon, le captage devient très variable: à des années de captage nul (par exemple 2002, 2005, 2007) ou faible (2009, 2010, 2011) succèdent des années excellentes voire pléthoriques (2003, 2006, 2008, 2012, 2014). A Marennes-Oléron, cette variabilité existe, mais s’avère beaucoup...
Tipo: Text
Palavras-chave: Huître creuse; Naissain; Recrutement; Captage; Larves; Cycle de reproduction; Changement climatique; Pacific oyster; Spat; Recruitment; Seed collecting; Larvae; Reproductive cycle; Climate change.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00334/44533/44240.pdf

Growth of the black-lip pearl oyster, Pinctada margaritifera, in suspended culture under hydrobiological conditions of Takapoto lagoon (French Polynesia)
Provedor de dados: 5
Autores: Pouvreau, Stephane; Tiapari, Jerome; Gangnery, Aline; Lagarde, Franck; Garnier, Matthieu; Teissier, Hinano; Haumani, G; Buestel, Dominique; Bodoy, Alain.
Growth of the black-lip pearl oyster, Pinctada margaritifera var. cumingi, was studied for an annual cycle, from March 1997 to April 1998, in the lagoon of Takapoto atoll (Tuamotu archipelago, French Polynesia). Growth in shell and in tissue were measured every 15 days on three successive age groups of cultivated pearl oysters. At the same time, hydrobiological parameters (temperature, salinity, oxygen concentration, suspended particulate matter), known to have influence on bivalve growth, were followed each week during culture. No seasonal trend was observed in hydrobiological parameters, except for temperature which varied between 26 degrees C and 31 degrees C. The potential food for pearl oysters (particulate organic matter, POM, mg l(-1)) was slightly...
Tipo: Text
Palavras-chave: Pearl culture; Matter in suspension; Biochemical composition; Length weight relations ship; Tropical lagoon; Growth; Pinctada margaritifera.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-381.pdf

In situ suspension feeding behaviour of the pearl oyster, Pinctada margaritifera: combined effects of body size and weather-related seston composition
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bodoy, Alain; Buestel, Dominique.
In situ clearance rate (CR) and biodeposition of the black pearl oyster, Pinctada margaritifera, were followed during several field experiments from 1996 to 1998 in the lagoon of Takapoto. Serial measurements of total particulate matter (TPM, mg l(-1)), particulate inorganic matter (PLM, mg l(-1)), and particulate organic matter (POM, mg l(-1)) were related to meteorological conditions, especially wind speed. As a general case, POM and PLM increased with wind speed. Nevertheless, PLM increased faster than POM so that the organic content (OC, %) of the TPM decreased progressively when wind speed increased. These TPM variations induced direct changes in feeding processes of P. margaritifera. CR (l h(-1)) averaged 22 l h(-1) for a pearl oyster of 1 g dry...
Tipo: Text
Palavras-chave: Biodeposition; Clearance rate; Seston; Filter feedings behaviour; Tropical lagoon; Tropical bivalve.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-382.pdf

Duality of trophic supply and hydrodynamic connectivity drives spatial patterns of Pacific oyster recruitment
Provedor de dados: 5
Autores: Lagarde, Franck; Fiandrino, Annie; Ubertini, Martin; Roque D'Orbcastel, Emmanuelle; Mortreux, Serge; Chiantella, Claude; Bec, Beatrice; Bonnet, Delphine; Roques, Cécile; Bernard, Ismael; Richard, Marion; Guyondet, Thomas; Pouvreau, Stephane; Lett, Christophe.
The recent discovery of Pacific oyster Crassostrea gigas (also known as Magallana gigas) spatfields in a Mediterranean lagoon intensely exploited for shellfish farming (Thau lagoon) revealed significant contrasts in spatial patterns of recruitment. We evaluated the processes that drive spatial patterns in oyster recruitment by comparing observed recruitment, simulated hydrodynamic connectivity and ecological variables. We hypothesized that spatial variability of recruitment depends on (1) hydrodynamic connectivity and (2) the ecology of the larval supply, settlement, metamorphosis, survival and biotic environmental parameters. We assessed recruitment at 6-8 experimental sites by larval sampling and spat collection inside and outside oyster farming areas...
Tipo: Text
Palavras-chave: Crassostrea gigas; Coastal lagoon; Larval ecology; Spatial patterns; Connectivity; Settlement; Recruitment; Oligotrophication.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00598/70981/69271.pdf

Association among growth, food consumption-related traits and amylase gene polymorphism in the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Huvet, Arnaud; Jeffroy, F; Fabioux, C; Daniel, Jean-yves; Quillien, Virgile; Van Wormhoudt, A; Moal, Jeanne; Samain, Jean-francois; Boudry, Pierre; Pouvreau, Stephane.
To examine further a previously reported association between amylase gene polymorphism and growth in the Pacific oyster Crassostrea gigas, ecophysiological parameters and biochemical and molecular expression levels of alpha-amylase were studied in Pacific oysters of different amylase genotypes. Genotypes that previously displayed significantly different growth were found to be significantly different for ingestion and absorption efficiency. These estimated parameters, used in a dynamic energy budget model, showed that observed ingestion rates (unlike absorption efficiencies) allowed an accurate prediction of growth potential in these genotypes. The observed association between growth and amylase gene polymorphism is therefore more likely to be related to...
Tipo: Text
Palavras-chave: Ingestion; Gene expression; Bivalve; Alpha amylase.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-5165.pdf

Ecophysiological model of growth and reproduction of the black pearl oyster, Pinctada margaritifera: potential applications for pearl farming in French Polynesia
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bacher, Cedric; Heral, Maurice.
A model of bioenergetics of the black pearl oyster (Pinctada margaritifera) was built to simulate growth, reproduction and spawning in suspended culture at field sites in Takapoto lagoon (French Polynesia). This model was based on allometric scaling of physiological functions and scope for growth (SFG) calculations. The input functions were clearance rate (CR, 1 day(-1)), retention efficiency (RE, %) for each kind of particle encountered in suspended matter, pseudofaeces and faeces productions (PF and F, mg C day(-1)), excretion and respiration rate (U and R, mg C day(-1)). The assimilated carbon (i.e., SFG, mg C day(-1)) was partitioned to the three internal state variables (somatic tissue, shell and gonad) according to the asymptotic increase of the...
Tipo: Text
Palavras-chave: Pearl farming; Food depletion; Scope for growth; Carrying capacity; Suspension feeding; Tropical lagoon.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-380.pdf

Spatial patterns in the condition index of the wild Pacific oyster Crassostrea gigas in a macrotidal coastal ecosystem: Influence of tidal processes and beyond
Provedor de dados: 5
Autores: Gasmi, Sonia; Bernard, Ismael; Pouvreau, Stephane; Maurer, Daniele; Schaal, Gauthier; Ganthy, Florian; Cominassi, Louise; Allain, Gwenhael; Sautour, Benoit; David, Valerie.
In macrotidal coastal ecosystems, spatial heterogeneity of the water column properties is induced by both oceanic and continental influences. Hydrodynamic processes generate a land-sea gradient of environmental conditions, affecting the biological performances of sedentary organisms. The aim of the present study is to establish an extensive spatial assessment in the reproductive investment of the wild Pacific oyster Crassostrea gigas in Arcachon Bay. This is done by looking for a relationship between the Lawrence and Scott condition index (LSCI) and two tidal processes: the immersion level (IL) and the local oceanic flushing time (LoFt). The LSCI of C. gigas was assessed, just before gamete release, at 68 sampling stations in Arcachon Bay. Oyster...
Tipo: Text
Palavras-chave: Reproductive investment; Crassostrea gigas; Macrotidal lagoon; Immersion level; Oceanic flushing; Environmental variability.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00357/46803/46670.pdf

A Dynamic Energy Budget (DEB) growth model for Pacific oyster larvae, Crassostrea gigas
Provedor de dados: 5
Autores: Rico-villa, Benjamin; Bernard, Ismael; Robert, Rene; Pouvreau, Stephane.
Tipo: Text
Palavras-chave: Dynamic Energy Budget; Crassostrea gigas; Bivalve larvae; Ecophysiology; Growth.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00009/11996/9040.pdf

Vers un retour de l'huître indigène en rade de Brest
Provedor de dados: 5
Autores: Duchene, Julie; Bernard, Ismael; Pouvreau, Stephane.
Fort appréciée du temps des Romains et très consommée jusqu’au XXème siècle, l’huître plate (Ostrea edulis), huître indigène de nos côtes européennes, ne tient plus aujourd’hui qu’une place anecdotique dans nos assiettes. En France, et plus précisément en Bretagne, des ostréiculteurs et des scientifiques se mobilisent afin d’envisager à nouveau une production durable de cette espèce fortement menacée.
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00270/38085/36220.pdf

The Native Oyster Restoration Alliance (NORA) and the Berlin Oyster Recommendation: bringing back a key ecosystem engineer by developing and supporting best practice in Europe
Provedor de dados: 5
Autores: Pogoda, Bernadette; Brown, Janet; Hancock, Boze; Preston, Joanne; Pouvreau, Stephane; Kamermans, Pauline; Sanderson, William; Von Nordheim, Henning.
Efforts to restore the native oyster Ostrea edulis and its associated habitats are gaining momentum across Europe. Several projects are currently running or being planned. To maximize the success of these, it is crucial to draw on existing knowledge and experience in order to design, plan and implement restoration activities in a sustainable and constructive approach. For the development of best practice recommendations and to promote multidimensional knowledge and technology exchange, the Native Oyster Restoration Alliance (NORA) was formed by partners from science, technology, nature conservation, consultancies, commercial producers and policy-makers. The NORA network will enhance scientific and practical progress in flat oyster restoration, such as in...
Tipo: Text
Palavras-chave: Ostrea edulis; Berlin Oyster Recommendation; Biogenic reef; Ecosystem service; Biodiversity.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00500/61192/64723.pdf

Molecular cloning and seasonal expression of oyster glycogen phosphorylase and glycogen synthase genes
Provedor de dados: 5
Autores: 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

Gametogenesis, reproductive investment, and spawning behavior of the Pacific giant oyster Crassostrea gigas: evidence of an environment-dependent strategy
Provedor de dados: 5
Autores: Enriquez-diaz, M.; Pouvreau, Stephane; Chavez-villalba, J.; Le Pennec, M.
The progress of gametogenesis was studied in oysters Crassostrea gigas having the same origin (Tremblade), but cultured during 1 year in two distinctive French marine areas, the Baie des Veys and Marennes-Ol,ron. We assessed seasonal changes in the reproduction cycle on the basis of stereological techniques to estimate reproductive investment and measurement of gonad evolution area by quantitative histology. From a qualitative point of view, both oyster groups presented typical reproductive stages, but showed differential timing, in particular during the sequence of spawning and duration of the re-absorption stage. Oysters in Baie des Veys had a single partial spawning in August and a re-absorption stage that extended until winter. Oysters in...
Tipo: Text
Palavras-chave: Stereology; Reproductive investment; Pacific oysters; Image analysis; Gametogenesis; Crassostrea gigas.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-7300.pdf

Metabolic adjustments in the oyster Crassostrea gigas according to oxygen level and temperature
Provedor de dados: 5
Autores: 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

Recruitment of the Pacific oyster Crassostrea gigas in a shellfish-exploited Mediterranean lagoon: discovery, driving factors and a favorable environmental window
Provedor de dados: 5
Autores: Lagarde, Franck; Roque D'Orbcastel, Emmanuelle; Ubertini, Martin; Mortreux, Serge; Bernard, Ismael; Fiandrino, Annie; Chiantella, Claude; Bec, Beatrice; Roques, Cecile; Bonnet, Delphine; Miron, Gilles; Richard, Marion; Pouvreau, Stephane; Lett, Christophe.
In the context of increasing demand for environmental recovery, aquatic systems may face the challenge of evolving under oligotrophication. This is the case in Mediterranean lagoons, in particular the shellfish-farmed Thau lagoon in France, where we studied recruitment of the Pacific oyster Crassostrea gigas. Oyster spat and environmental parameters were monitored at several sampling sites for 3 yr (2012 to 2014) using an original method with a temporal overlap deployment of collectors to study pre- and post-settlement processes and to identify the best conditions for recruitment. Contrary to the ‘no Pacific oyster reproduction’ paradigm in Mediterranean lagoons, our study showed that recruitment of this introduced species is possible in the Thau lagoon at...
Tipo: Text
Palavras-chave: Crassostrea gigas; Oyster spat; Pediveliger; Metamorphosis; Recruitment; Oligo trophication; Larval ecology.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00398/50899/51672.pdf

Growth of the black-lip pearl oyster, Pinctada margaritifera, at nine culture sites of French Polynesia: synthesis of several sampling designs conducted between 1994 and 1999
Provedor de dados: 5
Autores: Pouvreau, Stephane; Prasil, Vincent.
Between 1994 and 1999, several sampling designs were used to measure the growth of the black-lip pearl oyster, Pinctada margaritifera var. cumingi at different sites in French Polynesia. Using a common statistical method, growth data were analysed for nine sites and showed significant geographic variability. Parameters of the Von Bertalanffy model, fitted on the nine data sets, ranged from 147 to 186.5 mm for the H-infinity parameter and from 0.42 to 0.58 year(-1) for the k parameter. The phi parameter (combination of H-infinity and k) provided a ranking classification of growth in these nine sites: growth was low in closed atoll lagoons, such as Takapoto, whereas the island lagoons and ocean habitat supported a very promising shell growth. Calculated on...
Tipo: Text
Palavras-chave: Von Bertalanffy model; Tropical lagoon; Pinctada margaritifera; Pearl oyster; Growth; Modèle de Von Bertalanffy; Lagon tropical; Pinctada margaritifera; Huître perlière; Croissance.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-549.pdf

Déterminisme du recrutement larvaire de l’huître creuse (Crassostrea gigas) dans la lagune de Thau.
Provedor de dados: 5
Autores: Lagarde, Franck; Fiandrino, Annie; Richard, Marion; Bernard, Ismael; Mortreux, Serge; Ubertini, Martin; Chiantella, Claude; Boj, Marie; Meddah, Slem; Leurion, Axel; Soriano, Solenn; Fuhrmann, Marine; Le Gall, Patrik; Chiera, Caroline; Berteaux, Tom; Guillou, Jean-louis; Roque D'Orbcastel, Emmanuelle; Perignon, Adeline; Bonnet, Delphine; Roques, Cecile; Bec, Beatrice; Cochet, Helene; Gervasoni, Erika; Miron, Gilles; Pouvreau, Stephane.
Since spat mortality events that were firstly detected in 2008, Mediterranean shellfish industry seeks to exploit the Pacific oyster spat from lagoon natural recruitment. The CRCM, Cepralmar and Ifremer developed accordingly a research project named PRONAMED Phase 1 and 2 - 2010-2014, in order to define the economic potential of spatfall and improve knowledge of the reproductive cycle of Crassostrea gigas in this specific environmental context. The results of the past three year‘s study (2012, 2013, 2014) showed that broodstock have the ability to provide larvae after sexual maturation and spawning. A coincidence was noted between moon phase (new and full moon) and spawnings with an amplifying effect of storms on the intensity of spawning (Ubertini et al....
Tipo: Text
Palavras-chave: Lagune; Recrutement; Naissain; Huître creuse; Ecologie larvaire; Cycle de reproduction; Captage naturel.; Lagoon; Recruitment; Spat; Pacific oysters; Larval ecology; Reproduction Cycle; Natural spat collection.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00279/39054/37620.pdf

NMR relaxometry as a potential non-invasive routine sensor for characterization of phenotype in Crassostrea gigas
Provedor de dados: 5
Autores: 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

Influence of phytoplankton diversity and community structure on oyster reproduction (Arcachon Bay, France)
Provedor de dados: 5
Autores: Gonzales, Arriagada; Bernard, Ismael; Maurer, Daniele; Auby, Isabelle; Gasmi, Sonia; Pouvreau, Stephane; David, Valerie.
Arcachon Bay is one of the most important spat-supplying area for the French oyster production. During the last 16 years, the local economic activity of spat production has been threatened recurrently by a high interannual variability of seed harvesting. This threatened spat production was attributed to reproductive problems highlighted by both a delay in oyster spawning and a decrease of small larvae abundances since 1995. Recent works showed that these two reproduction indices seem closely related to climate change that might controls the phytoplankton communities of the Bay. Food availability in term of quantity and quality appears thus as a serious track to understand the reproductive problems of oyster in the Arcachon Bay. The aim of this work was...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00257/36828/35454.pdf