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| Registros recuperados: 170 | |
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| Renault, Tristan; Arzul, Isabelle. |
| Crassostrea gigas is increasingly being cultured in a great number of countries from animaIs originally introduced from Japan, and is one of the most exploited bivalve species in the EU (FAO, 1989). Although no serious pathogen was detected previously in Japanese oysters in Europe, mortalities have been observed since the introduction of this bivalve species into the EU. Thus, oyster cultivation may be endangered by the occurrence of epizootics, especially virus diseases, which are considered one of the maj or risks to production. Indeed, mortalities have been described among different species of ostreids and are associated with the presence of viruses belonging to various families. The first description of a virus was reported in adult Eastern oyters,... |
| Tipo: Text |
Palavras-chave: Pathology; Virology; Herpes-like infection; Detection; Diagnosis; Herpesviridae; Oyster; Crassostrea gigas; Mortality. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00044/15536/12915.pdf |
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| Akcha, Farida; Barranger, Audrey; Bachere, Evelyne; Berthelin, C. Heude; Piquemal, D.; Alonso, P.; Sallan, R. Rondon; Dimastrogiovanni, G.; Porte, C.; Menard, Dominique; Szczybelski, A.; Benabdelmouna, Abdellah; Auffret, M.; Rouxel, Julien; Burgeot, Thierry. |
| Genitors of the Pacific oyster Crassostrea gigas were submitted during gametogenesis to a short pulse exposure to the herbicide diuron at a realistic environmental concentration. Histological analysis showed no effect of diuron on gametogenesis course, sex ratio and reproductive effort. A non-significant increase in testosterone and progesterone levels was observed in genitors exposed to the herbicide. At cell level, diuron exposure was shown to modulate the phagocytic activity of circulating hemocytes. The results of a transcriptional analysis showed that diuron affected the expression of genes belonging to functions known to play a major role during oyster gametogenesis such as gene transcription regulation, DNA replication and repair, DNA methylation... |
| Tipo: Text |
Palavras-chave: Oyster; Pesticide; Reproduction; Histology; Gene expression; RT-qPCR; Steroid; Immunity. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00309/41983/83232.pdf |
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| Baud, Jean-pierre; Goyard, Emmanuel. |
| Variability of oyster quality at marketable size in winter was assesed by using a proportional sampling strategy based upon the yearly production of the oyster packing house. Landings per unit of production were estimated using the number of commercialized sanitary certification labels or/and the annual landings declared to the Veterinary Services. The range of variability for 15 parameters was estimated using the national monitoring network (REMORA) data outputs and a regional questionnaire. Both data sources showed similar results. Condition indices and morphological factors led to the highest variability. However, these conclusions should be confirmed by additional studies considering seasonal trends to assess the described quantitative relationships. |
| Tipo: Text |
Palavras-chave: Programme qualité; Huître creuses; Crassostrea gigas; Quality monitoring network; Oyster; Crasssotrea gigas. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00047/15871/13290.pdf |
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| Hatt, Philippe-jacques; Davenel, Armel; Eliat, Pierre-antoine; Quellec, Stephane. |
| To make a preliminary exploration of the possibilities and limits of magnetic resonance imaging (MRI) for assessing body growth and gonad development of the Pacific oyster, Crassostrea gigas, individual monitoring was conducted on diploid and triploid oysters in their second year, maintained from February to October in a pond on the French Atlantic coast. Magnetic resonance imaging was done on each oyster on five dates during the study period. From these images, variations in the volumes of the flesh, digestive gland-gonad and adductor muscle, and the surface of the gills were measured over time. Apart from the well known differences between diploids and triploids related to maturation of gametes, other original observations of assessing growth were made... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Oyster; Gonad development; Growth; Magnetic resonance imaging; MRI. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6872.pdf |
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| Dupuy, Christine; Vaquer, André; Lam Hoai, Thong; Rougier, Claude; Mazouni, Nabila; Lautier, Jacques; Collos, Yves; Le Gall, Solange. |
| The Mediterranean Thau Lagoon is an important oyster farming area in Europe. Oyster growth rates are among the highest in France, although chlorophyll a concentration is low. Previous studies have demonstrated that picophytoplankton, nano-microphytoplankton, dinoflagellates and loricate ciliates such as tintinnids are abundant. However, heterotrophic flagellates and aloricate ciliates have not been investigated. The aim of this study was to assess picophytoplankton, protist and zooplankton abundances in the Lagoon and to investigate the particular structure of the microbial food web, which may explain such paradoxical oyster growth. In oligotrophic waters in the Thau Lagoon, the picoeukaryote Ostreococcus tauri is the dominant autotrophic picoplankter,... |
| Tipo: Text |
Palavras-chave: Trophic link; Picophytoplankton; Heterotrophic protist; Microbial food web; Thau Lagoon; Food source; Oyster; Bivalve. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-812.pdf |
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| Royer, J; Ropert, Michel; Costil, K. |
| Summer mortalities have been observed in French shellfish areas (including Normandy) since 1994, but origin of this syndrome remains unclear and is suspected to be caused by a combination of several interacting extrinsic (biotic and abiotic) and intrinsic (genetic, physiological, immunological) factors. The French research program, MOREST aimed to identify the origin of oyster summer mortality along the French coast, focusing on the interactions between oysters, their pathogens, and the environment. The present study analyzed spatio-temporal variation in growth, condition and mortality in spat, and half-grown and market-sized oysters reared from February 2000 to October 2003 at six stations within two different areas in the Bay of Veys, Normandy: Grandcamp... |
| Tipo: Text |
Palavras-chave: France English Channel; Growth; Summer mortality; Crassostrea gigas; Oyster. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-4733.pdf |
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| Arzul, Isabelle; Miossec, Laurence; Blanchet, Estelle; Garcia, Celine; Francois, Cyrille; Joly, Jean-pierre. |
| Bonamiosis due to the intrahaemocytic protistan parasite Bonamia ostreae is a European endemic disease affecting flat oysters Ostrea edulis. After its first description in June 1979 in L'Ile Tudy, Brittany, the parasite rapidly spread to all French oyster farming areas and in other European countries through transfers of live molluscs. Bonamiosis and marteiliosis, another protozoan disease appeared in the seventies, drastically reduced the French flat oyster production from 20 000 tonnes in 1970 to less than 2000 tonnes after 1981. In 2001, about 1650 t of flat oysters were marketed in France. The production is restricted to several areas specialised in reproduction, growth and/or marketing, and depends on transfers of animals. Most important production... |
| Tipo: Text |
Palavras-chave: Bonamia ostreae; Parasitology; Pathology; Ostrea edulis; Oyster. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-6381.pdf |
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| Lanceleur, Laurent; Schaefer, Joerg; Chiffoleau, Jean-francois; Blanc, Gerard; Auger, Dominique; Renault, Sophie; Baudrimont, Magalie; Audry, Stephane. |
| The Gironde fluvial estuarine system is impacted by historic metal pollution (e.g. Cd, Zn, Hg) and oysters (Crassostrea gigas) from the estuary mouth have shown extremely high Cd concentrations for decades. Based on recent work (Chiffoleau et al., 2005) revealing anomalously high Ag concentrations (up to 65 mg kg(-1); dry weight) in Gironde oysters, we compared long-term (similar to 1955-2001) records of Ag and Cd concentrations in reservoir sediment with the respective concentrations in oysters collected between 1979 and 2010 to identify the origin and historical trend of the recently discovered Ag anomaly. Sediment cores from two reservoirs upstream and downstream from the main metal pollution source provided information on (i) geochemical background... |
| Tipo: Text |
Palavras-chave: Silver; Cadmium; Estuary; Oyster; Biomonitoring. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00060/17109/15071.pdf |
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| Lallias, Delphine; Taris, Nicolas; Boudry, Pierre; Bonhomme, Francois; Lapegue, Sylvie. |
| he European flat oyster (Ostrea edulis L.) is a marine bivalve whose natural geographical distribution ranges along the European Atlantic coast from Norway to Morocco, in addition to the Mediterranean and Black Sea. Previous studies of allozymes, microsat-ellites and mitochondrial differentiation over the whole range concluded that a significant divergence existed between Mediterranean and Atlantic populations, together with an isolation-by-distance pattern. However, the average mitochondrial haplotypic diversity displayed a high among populations variance, reflecting smaller effective population size in some locations. Additionally, a ten-fold quantitative difference was observed in the same study in Fst between the mitochondrial and the nuclear genomes,... |
| Tipo: Text |
Palavras-chave: Genotypes; Genetic diversity; Breeding success; Allozymes; Population genetics; Parentage analyses; Natural population; Ostrea edulis; Oyster. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-3334.pdf |
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| Frechette, Marcel; Goulletquer, Philippe; Daigle, Gaétan. |
| Japanese cupped oysters suffer summer mortality in many culture sites along the French Atlantic coast. To ascertain whether mortality might be associated with morphological features of the shells, we estimated fluctuating asymmetry (FA) of hatchery/nursery-produced oysters kept in culture bags in the intertidal. FA is defined as random variations from a perfect symmetry plane (bilateral or radial) in some morphological trait. FA increases with disruption of homeostasy during ontogeny and has both genetic and environmental determinants. We found significant differences in FA between dead and live oysters in two of our three study groups. Therefore, lack of developmental stability may be involved in the summer mortality syndrome of oysters. We also found... |
| Tipo: Text |
Palavras-chave: Oyster; Mortality; Fluctuating asymmetry; Aquaculture. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-575.pdf |
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| Arzul, Isabelle; Bond, Celine; Gagnaire, Beatrice; Chollet, Bruno; Morga, Benjamin; Ferrand, Sylvie; Robert, Maeva; Renault, Tristan. |
| Bonamiosis due to the intrahaemocytic protistan parasite Bonamia ostreae is a European endemic disease affecting flat oysters Ostrea edulis. The parasite has been described in different ecosystems from estuaries to open sea and no clear correlations could be demonstrated between the development of the disease and environmental parameters such as temperature or salinity. The parasite life cycle, including its survival outside the host is not completely known. Nevertheless, the infection can be directly transmitted by cohabitation between infected and non infected oysters suggesting that the parasite does not need intermediate host to complete its cycle. In the present study, the impact of temperature and salinity on the survival of purified parasites... |
| Tipo: Text |
Palavras-chave: Effects; Temperarature; Salinity; Bonamia ostreae; Parasite; Pathology; Flat oyster; Ostrea edulis; Oyster. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/acte-3375.pdf |
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| Haure, Joel; Baud, Jean-pierre. |
| A study on mortalities, growth and fattening of the oyster Crassostrea gigas was carried out spring with the autumn 1987 in four sites of bay of Bourgneuf. Mortalities, more important in spring, prove to be higher in the sectors North compared to the Southern sectors of bay of Bourgneuf. The performances of growth are rather weak when they are compared with other French oyster sectors. They however present a better production in the cattle-breeding areas located at the South of bay. The spring phase is marked by the formation of glucidic reserves, at the moment of the reheating of water, which is quickly transformed, in the majority of the sites, in lipids of reserves of the ovocytes, during the gamétogenèse. The state of fattening of Crassostrea gigas... |
| Tipo: Text |
Palavras-chave: Fattening; Oyster; Mortality; Growth; Bay of Bourgneuf; Crassostrea gigas; Engraissement; Huitre; Mortalité; Croissance; Baie de Bourgneuf; Crassostrea gigas. |
| Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/1990/rapport-1646.pdf |
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| Leitao, Alexandra; Boudry, Pierre; Thiriot Quievreux, Catherine. |
| The G-banding technique was performed on aneuploid karyotypes from gill tissue of the Pacific oyster, Crassostrea gigas, to assess whether chromosome losses could be explained by differential chromosomal susceptibility and to clarify the negative correlation between aneuploidy and growth rate previously reported in different populations of this oyster. The study of 95 G-banded aneuploid karyotypes showed that only 4 of the 10 chromosome pairs (viz. 1, 5, 9, and 10) of C. gigas were affected by the loss of one homologous chromosome. Pairs 1, 9, and 10, which were lost in 56, 33, and 44% of cases, respectively, may be considered to be differentially affected. Hypotheses on this differential chromosomal susceptibility are discussed. |
| Tipo: Text |
Palavras-chave: Oyster; Karyotype; G banding; Growth; Aneuploidy; Huître; Caryotype; Bandes G; Croissance; Aneuploïdie. |
| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-742.pdf |
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| Normand, Julien; Ernande, Bruno; Boudry, Pierre. |
| Today, triploidy is the most common method used to genetically improve marine bivalve aquaculture production. In the Pacific oyster Crassostrea gigas, triploidy affects many traits. The most proeminent one is reproductive effort, which is greatly reduced compared to diploids. The combined effects of physiological trade-offs between survival, growth and reproduction together with the reduction of reproductive effort in triploids explains the global enhancement of yield observed. However, the sterility of triploid oysters is only partial and some triploid individuals can show normal gametogenesis (i.e. similar to diploids), especially under warm conditions. In diploid oysters, the heritability of reproductive effort has been shown to be relatively low, but a... |
| Tipo: Text |
Palavras-chave: Parentage analysis; Triploidy; Oyster; Quantitative genetics; Gametogenesis. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/acte-4525.pdf |
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| Gueguen, Yannick; Herpin, Amaury; Aumelas, André; Garnier, Julien; Fievet, Julie; Escoubas, Jean-michel; Bulet, Philippe; Gonzalez, Marcelo; Lelong, Christophe; Favrel, Pascal; Bachere, Evelyne. |
| In invertebrates, defensins were found in arthropods and in the mussels. Here, we report for the first time the identification and characterization of a defensin (Cg-Def) from an oyster. Cg-def mRNA was isolated from Crassostrea gigas mantle using an expressed sequence tag approach. To gain insight into potential roles of Cg-Def in oyster immunity, we produced the recombinant peptide in Escherichia coli, characterized its antimicrobial activities, determined its solution structure by NMR spectroscopy, and quantified its gene expression in vivo following bacterial challenge of oysters. Recombinant Cg-Def was active in vitro against Gram-positive bacteria but showed no or limited activities against Gram-negative bacteria and fungi. The activity of Cg-Def was... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Genomic library; Microbiology; Defensin; Oyster. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2127.pdf |
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| Beiras, Ricardo; His, Edouard. |
| The effects of mercury (Hg) concentrations ranging from 0 (control) to 1024 µg 1-1 upon embryogenesis, survival, growth and metamorphosis of Crassostrea gigas (Thunberg) oyster larvae were investigated. Embryogenesis was abnormal in 50 % of the individuals at 11 µg 1-1 . The 48 h LD50 for D·shaped, umbonate and pediveliger larvae were 33, 115 and 200 µg 1-1 respectively. The increase in LD50 was partially explained by the larval weight increase, although weight-specific tolerance to Hg was higher in smaller larvae. Growth, the most sensitive physiological process studied, was significantly retarded at 4 µg 1-1. The metamorphosis rate was significantly reduced when competent pediveligers were exposed to 64 µg 1-1 for 48 h prior to the addition of the... |
| Tipo: Text |
Palavras-chave: Mercury; Oyster; Larvae; Embryo; Bioassay; Ecotoxicology; Crassostrea gigas. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00037/14867/12191.pdf |
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| Pernet, Fabrice; Tamayo, David; Petton, Bruno. |
| Mortalities of oyster seed of Crassostrea gigas associated with ostreid herpes virus OsHV-1 μVar have been observed in many oyster producing countries since 2008. The objective of this study was to further investigate whether low temperature treatments can offer a viable option to mitigate oyster mortalities. An experiment was set-up to further evaluate the effect of low temperature treatments (10 and 13°C vs. 21°C) and their duration (6 d to 83 d) on the survival of oysters previously infected with OsHV-1 μVar by means of exposure to field conditions in areas where mortalities were occurring. Average survival of oysters infected with OsHV-1μVar was 71% after 83 d at low temperatures compared to only 23% in controls maintained at 21°C. During... |
| Tipo: Text |
Palavras-chave: Bivalve; Disease; OsHV-1; Oyster; Temperature; Virus. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00259/37047/35555.pdf |
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| Buchet, Vincent; Bluteau, A. |
| Whatever the hydraulic gestion, an épuration of the fishes sewages is possible with the integrated system studied. The main action is situed in the intermediary pond with a significant decrease of nutrients, especially ammonia, and particulate mineral matters. The oyster's pond have no significant action on nutrients, but their action is real on chlorophyll which become limiting factor in 20% renewal system. One of the effluent, system 1 (renewal 10%) had high suspended matter and low nutrient concentrations. The other (renewal 20%) was poor in supcnded matters (chlorophyll). The system 2 give best oyster's growth, close to traditional nursery performances, with an highest mortality (32%). In the first system, suspended matter concentrations are too high... |
| Tipo: Text |
Palavras-chave: Valorization; Oyster; Pre ongrowing; Seabass; Integrated rearing; Valorisation; Huître; Prégrossissement; Bar; Elevage intégré. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/1996/rapport-1917.pdf |
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| Degremont, Lionel; Bedier, Edouard; Soletchnik, Patrick; Ropert, Michel; Samain, Jean-francois; Boudry, Pierre. |
| The French project "Morest", coordinated by IFREMER, aims to a better understanding of the causes of summer mortalities in juvenile oysters by a multidisciplinary approach. Within this program, a first generation (G1) was bred in 2001 to assess to what extent genetic variability exists for this trait in French populations. 17 half-sib families (HSF) including 44 full-sib families (FSF) were obtained in the G1, and each FSF was reared in three sites along the French coast during the summer period. Significant differences in survival were observed among HSF, clearly indicating a genetic basis for survival. Estimation of heritability for survival was very high: 0.81  0.29. In 2002, 3 "good" HSF and 3 "bad" HSF were selected on their survival... |
| Tipo: Text |
Palavras-chave: Selection; Genetic; Mortalities; Crassostrea gigas; Oyster. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/acte-3439.pdf |
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| Registros recuperados: 170 | |
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