|
|
|
Registros recuperados: 115 | |
|
|
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 |
| |
|
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
|
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
|
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
|
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
|
|
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 |
| |
Registros recuperados: 115 | |
|
|
|