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Plouzane, France

The Institut français de recherche pour l'exploitation de la mer is an oceanographic institution in France. Wikipedia.

Agency: Cordis | Branch: H2020 | Program: CSA | Phase: BG-16-2015 | Award Amount: 2.02M | Year: 2016

CSA Oceans 2 is a 36 month project with the general aim to facilitate and support the implementation of the Strategic Research and Innovation Agenda (SRIA) of JPI Oceans. CSA Oceans 2 will build further on the outcomes of the FP7 CSA Oceans project. To achieve the objective above the project has been organised in five work packages: - WP1 will allow to link closely the project with the JPI Oceans structures namely the Management Board, the Executive Committee, Strategic Advisory Board and the JPI Oceans Secretariat and involve them in the CSA activities - WP2 will deal with the implementation of joint transnational activities and will facilitate the organisation of the activities, it will guide the member countries in identifying and selecting the best fit for purpose (new) tools and provide a framework for evaluating, assessing and monitoring of the actions - WP3 aims at maintaining and further developing the relationships between JPI Oceans with different relevant actors (research funding organisations (RFOs), Ministries, research performing organisations (RPOs), industry and partners outside of the EU) in the field of marine and maritime sciences in supporting the implementation of JPI Oceans agreed actions - WP4 will support the implementation of the SRIA through thematic foresight mechanisms and will design a process for JPI Oceans to update its SRIA, Implementation Plan and Operational plan. - WP5 will deliver the necessary tools for the information management as well as outreach and dissemination of CSA Oceans 2 project and JPI Oceans activities. The CSA Oceans 2 project will be performed by a consortium of a mix of funding, coordinating and research performing organisations. All are members of the JPI Oceans Management Board or have a close connection to their national Management Board member.

Degremont L.,French Research Institute for Exploitation of the Sea
Aquaculture | Year: 2011

During the MOREST project (2001-2006), oyster summer mortality was extensively investigated in Crassostrea gigas in France. However, significant increases in magnitude and geographic distribution of summer mortality episodes have been reported since 2008. This paper investigates the response to selection for survival, which was successfully performed between 2001 and 2003, in this new context. It also examines the relationship between the mortality and the three pathogens Vibrio aestuarianus, V. splendidus and the Ostreid herpesvirus 1 (OsHV-1). Three batches of juvenile (6-month-old) Crassostrea gigas were produced in February 2009 and tested in the field in the Marennes-Oléron Bay during summer (August and September) 2009: one control batch, one batch descended from one family selected to be resistant (R) to the summer mortality phenomenon and one descended from one family selected to be susceptible (S). For each batch, mortality was monitored and oysters were diagnosed for the presence and intensity of the three pathogens. A mortality episode started 11. days post deployment and had finished by day 17. A significant difference in mortality was found among the batches, with 5, 53 and 94% for the R, control and S batches, respectively. This finding indicates that the selection previously made for resistance to summer mortality still confers an advantage for the survival of juvenile C. gigas to descendant batches in the context of the recent massive oyster mortality that has occurred in France since 2008. Disease diagnoses revealed V. splendidus at all sampling dates but never V. aestuarianus, showing that only the first of these bacteria could have been involved in this mortality event. However correlations between the mortality and the presence or the bacterial load of V. splendidus were weak, negative and not significant. In contrast, high and significant correlations were found between the mortality and the prevalence of OsHV-1, as well as between the mortality and OsHV-1 viral load. This study clearly revealed the suddenness of the infection in juvenile C. gigas in field conditions, as no OsHV-1 was detected in seed at deployment, while all juvenile oysters tested 7. days post-deployment were infected and the peak of the viral load was observed 11. days post-deployment. Finally, this study is the first report of herpesvirus resistance in the R oysters. Even if all R oysters had been infected by the OsHV-1, they were able, first, to limit the amount of the viral load in their tissues, and, second, either to eliminate the virus from their tissue or to decrease the quantity of viral DNA to a level below the threshold of the real-time PCR technique, as OsHV-1 prevalence decreased from 100% to 33% for the R oysters screened at 7 and 17. days post-deployment, respectively. © 2011 Elsevier B.V.

Degremont L.,French Research Institute for Exploitation of the Sea
Aquaculture | Year: 2013

As with summer mortalities reported in France between 2001 and 2006, mortality caused by the Ostreid herpesvirus 1 (OsHV-1) in Crassostrea gigas affects mostly juveniles, although adults can also be impacted to a small extent. This could suggest that both mortalities have similar causes and that establishment of resistance, in particular to the Ostreid herpesvirus 1 (OsHV-1), depends on either the size or the age of oysters. The present study reports an investigation of both size and age using three cohorts produced during winter and three produced during summer. Each cohort contained oysters genetically selected to be resistant or susceptible to the summer mortality phenomenon, as well as unselected control oysters. Any abnormal mortality was recorded between production and placement in the field. Transfer to field conditions was then made over thirty deployments between July 2009 and September 2011. All mortalities occurred when seawater temperature was above 16°C, which was termed the 'risk' period. For all deployments made during the risk period, mortality was observed within two weeks post-deployment and most episodes lasted over a week. For deployments made outside of the risk period, mortality occurred as soon as the next risk period began. The absence of detection of OsHV-1 at deployment, the presence of a high viral load of OsHV-1 (>10+6 DNA copies per mg of fresh tissue) on moribund oysters sampled during peak mortality, and the mortality kinetic all suggest that the mortalities can be attributed to this pathogen alone. The major finding of this study was that the resistance to mortality caused by OsHV-1 increased with both age and size, suggesting a maturation of the immune system against the virus. In field conditions, the relationship between mortality and size was stronger than the relationship between mortality and age. Regression equations of oyster size or age at the onset of the mortality event were derived to estimate the mortality due to OsHV-1. Although larger animals always tended to be more resistant to OsHV-1 than smaller ones, mortality in unselected oysters remained high (>70%) for the size range 0-10g. Selective breeding to improve resistance to OsHV-1 remains the best way to significantly reduce mortality; however, prudent management strategies for oyster growers could also potentially offer viable solutions. For example, deploying juveniles at a site favouring the growth of oysters after the threat of exposure to OsHV-1 has passed (i.e. at the end of the risk period), and by using cultural practices favouring high growth and/or a site for which the risk period is short due to the seawater temperature. Use of triploid oysters or lines selected for higher growth is also discussed. © 2013 Elsevier B.V.

Francoise L.,French Research Institute for Exploitation of the Sea
Food Microbiology | Year: 2010

Lactic acid bacteria (LAB) in fish flesh has long been disregarded because the high post-mortem pH, the low percentage of sugars, the high content of low molecular weight nitrogenous molecules and the low temperature of temperate waters favor the rapid growth of pH-sensitive psychrotolerant marine Gram-negative bacteria like Pseudomonas, Shewanella and Photobacterium. In seafood packed in both vacuum (VP) and modified atmosphere (MAP) packaging commonly CO2 enriched, the growth of the Gram-negative aerobic bacteria group (predominantly pseudomonads) is effectively inhibited and the number reached by LAB during storage is higher than that achieved in air but always several log units lower than the trimethylamine oxide (TMA-O) reducing and CO2-resistant organisms (Shewanella putrefaciens and Photobacterium phosphoreum). Accordingly, LAB are not of much concern in seafood neither aerobically stored nor VP and MAP. However, they may acquire great relevance in lightly preserved fish products (LPFP), including those VP or MAP. Fresh fish presents a very high water activity (aw) value (0.99). However, aw is reduced to about 0.96 when salt (typically 6% WP) is added to the product. As a result, aerobic Gram-negative bacteria are inhibited, which allows the growth of other organisms more resistant to reduced aw, i.e. LAB, and then they may acquire a central role in the microbial events occurring in the product. Changes in consumers' habits have led to an increase of convenient LPFP with a relative long shelf-life (at least 3 weeks) which, on the other hand, may constitute a serious problem from a safety perspective since Listeria monocytogenes and sometimes Clostridium botulinum (mainly type E) may able to grow. In any case the LAB function in marine products is complex, depending on species, strains, interaction with other bacteria and the food matrix. They may have no particular effect or they may be responsible for spoilage and, in certain cases, they may even exert a bioprotective effect in relation to undesirable bacteria. The bioprotective potential of endogenous LAB in relation to pathogens and spoiling bacteria has often been highlighted. However, the technology is still in its infancy compared with foods dairy and meat products in which either the carbohydrate content (dairy products) or sugar and salt added (meat products) favor the acidification by LAB that enable a natural preservation of the product. Successful studies on LAB as probiotic for fish intensify, but this potential is still to be explored for human. Although not usual, some applications of LAB for fermentation of marine products and by-products are described. © 2010 Elsevier Ltd.

Marine bivalves show among the greatest allozyme diversity ever reported in Eukaryotes, putting them historically at the heart of the neutralist-selectionist controversy on the maintenance of genetic variation. Although it is now acknowledged that this high diversity is most probably a simple consequence of a large population size, convincing support for this explanation would require a rigorous assessment of the silent nucleotide diversity in natural populations of marine bivalves, which has not yet been done. This study investigated DNA sequence polymorphism in a set of 37 nuclear loci in wild samples of the flat oyster Ostrea edulis. Silent diversity was found to be only moderate (0.7%), and there was no departure from demographic equilibrium under the Wright-Fisher model, suggesting that the effective population size might not be as large as might have been expected. In accordance with allozyme heterozygosity, nonsynonymous diversity was comparatively very high (0.3%), so that the nonsynonymous to silent diversity ratio reached a value rarely observed in any other organism. We estimated that one-quarter of amino acid-changing mutations behave as neutral in O. edulis, and as many as one-third are sufficiently weakly selected to segregate at low frequency in the polymorphism. Finally, we inferred that one oyster is expected to carry more than 4800 non-neutral alleles (or 4.2 cM(-1)). We conclude that a high load of segregating non-neutral amino-acid polymorphisms contributes to high protein diversity in O. edulis. The high fecundity of marine bivalves together with an unpredictable and highly variable success of reproduction and recruitment (sweepstakes reproduction) might produce a greater decoupling between Ne and N than in other organisms with lower fecundities, and we suggest this could explain why a higher segregating load could be maintained for a given silent mutation effective size.

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