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Registros recuperados: 26 | |
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Bouilly, Karine; Leitao, Alexandra; Mccombie, Helen; Chaves, R.; Guedes Pinto, H; Boudry, Pierre; Lapegue, Sylvie. |
In the Pacific oyster, Crassostrea gigas hypodiploid aneuploid cells with 2n=19, 18 or 17 chromosomes have regularly been reported. There is a negative correlation between somatic aneuploidy and growth rate in oysters (Leitão et al., 2001a) as well as evidence for a genetic basis (Leitão et al., 2001b). Furthermore, non-random chromosome loss has been demonstrated in aneuploid karyotypes of C. gigas using the G-banding technique (Leitão et al., 2001c). This poster summarises different studies used to investigate the effects of the herbicide atrazine on the level of aneuploidy in this species |
Tipo: Text |
Palavras-chave: Genetic; Aneuploidy; Toxicology; Impact; Atrazine; Crassostrea gigas; Pacific oysters. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-3489.pdf |
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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 |
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Leprêtre, Maxime; Faury, Nicole; Segarra, Amelie; Claverol, Stéphane; Degremont, Lionel; Palos-ladeiro, Mélissa; Armengaud, Jean; Renault, Tristan; Morga, Benjamin. |
Massive mortality outbreaks affecting Pacific oysters (Crassostrea gigas) spat/juveniles are often associated with the detection of a herpesvirus called ostreid herpesvirus type 1 (OsHV-1). In this work, experimental infection trials of C. gigas spat with OsHV-1 were conducted using two contrasted Pacific oyster families for their susceptibility to viral infection. Live oysters were sampled at 12, 26, and 144 h post infection (hpi) to analyze host-pathogen interactions using comparative proteomics. Shotgun proteomics allowed the detection of seven viral proteins in infected oysters, some of them with potential immunomodulatoy functions. Viral proteins were mainly detected in susceptible oysters sampled at 26 hpi, which correlates with the mortality and... |
Tipo: Text |
Palavras-chave: Proteomics; Interactions; Antiviral response; OsHV-1; Pacific oysters. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00669/78075/80307.pdf |
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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 |
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Boudry, Pierre; Leitao, Alexandra; Mccombie, Helen; Thiriot-quievreux, Catherine. |
Cytogenetic abnormalities arising both in mitosis and meiosis are known to be common in bivalves. Here we review result obtained from the observations of somatic aneuploidy in different populations of the commercially important Pacific oyster, Crassostrea gigas. The oysters studied were either (1) produced in IFREMER hatcheries between 1986 and 1999, (some of these were part of the EU funded programme GENEPHYS); or (2) collected from wild populations along the French Atlantic coast. Chromosome numbers were scored from 30 mitotic metaphases in gill tissue per individual studied. Aneuploid cells (2n - X) were observed in all the 13 populations studied. A highly significant negative correlation was observed between the level of aneuploidy and growth, i.e.... |
Tipo: Text |
Palavras-chave: Growth; Genetic; Aneuploidy; Crassostrea gigas; Pacific oysters. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/acte-3446.pdf |
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Huvet, Arnaud; Degremont, Lionel; Labreuche, Yannick; Daniel, Jean-yves; Dubrunfaut, Thomas; Boudry, Pierre; Haure, Joel; Bedier, Edouard; Ropert, Michel; Herpin, Amaury; Cunningham, Charles; Moal, Jeanne; Samain, Jean-francois. |
Summer mortality associated with juveniles of the oyster Crassostrea gigas is the result of a complex interaction between the host, pathogens and environment. Divergent selection based on summer survival have been applied to produce families with resistant and susceptible progeny. Here, we describe the use of suppression subtractive hybridization to generate 150 clones that were differentially regulated between resistant and susceptible F2 progeny. The nucleotide sequence of these 150 clones was determined. Among the 25 unique sequences that matched with the products of known genes, those putatively implicated in energy generation (12%) and immune function (16%), systems suspected to be implicated in summer mortality, were extended and analyzed by real... |
Tipo: Text |
Palavras-chave: Selection; Gene; Genetic; Summer mortality; Crassostrea gigas; Pacific oysters. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3447.pdf |
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Boudry, Pierre; Haffray, Pierrick. |
The most significant genetic improvement for the production of Pacific oyster (Crassostrea gigas) in France to date has been through the breeding of triploids, especially since the development of tetraploids. Triploid oysters commonly resist summer mortality better than diploids. This is most probably because reproductive allocation is so important in this phenomenon. Quantitative genetics studies strongly suggest that a significant gain in resistance to summer mortality, or other traits of interest, could be obtained by selective breeding. Practical difficulties however, and the high cost of breeding large numbers of families under common conditions over many generations remain major constraints to family-based selective breeding in oysters. In the last... |
Tipo: Text |
Palavras-chave: Polyploidization; Selective breeding; Genetic; Crassostrea gigas; Pacific oysters. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-3438.pdf |
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Taris, Nicolas; Sauvage, Christopher; Boudry, Pierre. |
Oysters, like many marine bivalves, are characterized by very high fecundity and low survival rate at early stages of life. Rearing conditions in hatcheries (i.e. density, feeding, temperature...) are different from those observed in the wild. Additionally, slow growing larvae are culled by sieving. As previous studies have shown that genetic variability exists for several early development traits, we aimed to assess if common hatchery rearing practices exert specific selective processes at the larval stage. In order to avoid possible bias and to increase the number of families studied, we used a mixed-family approach with subsequent parentage analysis using a recently developed set of three multiplexed microsatellite markers. We studied the variance in... |
Tipo: Text |
Palavras-chave: Hatcheries; Selection; Genetic drift; Genetic; Crassotrea gigas; Pacific oysters. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-3483.pdf |
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Ernande, Bruno; Haure, Joel; Degremont, Lionel; Bedier, Edouard; Boudry, Pierre. |
Phenotypic and genetic correlations between fitness-related life-history traits - such as survival, growth and reproductive allocation - have to be considered to better understand selective processes, both in the wild and in breeding programs. Quantitative genetic experiments, based on nested half-sib mating designs, were perfomed in the Pacific oyster C. gigas (1) to estimate genetic variance and the response to selection and (2) to document phenotypic and genetic trade-offs between life history traits. Physiological trade-offs, i.e. plastcity of resource allocation, were shown to vary among genotypes. Genetic polymorphism was primarily observed for the the plasticity of reproductive effort. In addition, the degree of plasticity in reproductive effort... |
Tipo: Text |
Palavras-chave: Genetic polymorphism; Genetic; Plasticity; Genetical basis; Crassostrea gigas; Pacific oysters. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/acte-3443.pdf |
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Burge, Colleen; Judah, Linda; Conquest, Loveday; Griffin, Frederick; Cheney, Daniel; Suhrbier, Andrew; Vadopalas, Brent; Olin, Paul G.; Renault, Tristan; Friedman, Carolyn S.. |
Summer seed mortality (SSM) has occurred yearly in Tomales Bay, California since 1993. SSM has resulted in up to 90% cumulative losses, and has been associated with extreme temperature, phytoplankton blooms, and an oyster herpesvirus. In this study, three stocks of Pacific oysters were planted at three sites in California (Inner Tomales Bay, Outer Tomales Bay, and Bodega Harbor) in October of 2000 (Fall) and April of 2001 (Spring) and monitored for mortality, growth, and health status. In April of 2001, a similar study was conducted in Totten Inlet, WA state using cohorts of oysters planted in California; animals were monitored for mortality and growth. Temperature data were collected at all sites; phytoplankton abundance data were collected at the... |
Tipo: Text |
Palavras-chave: California; Tomales Bay; Oyster herpesvirus; Temperature; Mortality; Crassostrea gigas; Pacific oysters. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2976.pdf |
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Degremont, Lionel; Boudry, Pierre; Soletchnik, Patrick; Bedier, Edouard; Ropert, Michel; Samain, Jean-francois. |
Three successive generations were produced between 2001 and 2003 to assess to what extent genetic variability exists for this trait in juvenile oysters Crassostrea gigas. For each generation, two groups were selected for their high ("R" for resistant) and low ("S" for susceptible) survival. Significant differences of mortality were observed during the first year in Rivière d'Auray (RA) (Brittany-France). However, low and similar mortality were observed for both groups, with no significant difference between groups in the first and second generation in this site, where the first summer is the critical sensitive period with a clear age effect. In Baie des Veys (BDV) (Normandie-France), where mortalities usually mainly affect adults, mortality between... |
Tipo: Text |
Palavras-chave: Genetic variability; Genetic; Summer mortality; Crassostrea gigas; Pacific oysters. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3442.pdf |
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Hubert, Francoise; Morga, Benjamin; Renault, Tristan; Le Guyader, Soizick. |
Aims This study was performed to develop passive sampling methodology for the detection of two viruses in seawater in the area of shellfish production, The Norovirus (NoV), a human pathogen implicated in gastroenteritis outbreaks linked to oyster consumption and the ostreid herpesvirus type 1 (OsHV-1) a virus associated with mass mortalities of Pacific oysters. Methods and Results Commercially membranes were tested for their capacity to adsorb virus: Zetapor, gauze, nylon, low density polyethylene (LDPE) and Polyvinylidene difluoride (PVDF). Laboratory exposures of membranes to contaminated water samples (stool, sewage, seawater) were performed. Our data shown that the amount of NoV GII genome per membrane measured with qRT-PCR increased with the time of... |
Tipo: Text |
Palavras-chave: Norovirus; OsHV-1; Pacific oysters; Passive samplers; Seawater; Sewage. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00365/47646/47670.pdf |
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Boudry, Pierre. |
The most significant genetic improvement for the production of Pacific oyster (Crassostrea gigas) up until now has been obtained through the production of triploids, particularly since the development of tetraploids in the mid 90s. Alternatively, quantitative genetics studies suggest that significant gains could be obtained in traits of aquacultural interest. However, the limited extent of hatchery propagation (compared with natural recruitment) in some countries and/or technical difficulties and biological characteristics of this species have retarded the development of selective breeding programs for C. gigas. Individual selection can however be performed easily in such a highly fecund species, though it often leads to small effective population sizes... |
Tipo: Text |
Palavras-chave: Selective breeding; Genetic; Crassostrea gigas; Pacific oysters. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/acte-3462.pdf |
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Taris, Nicolas; Sauvage, Christopher; Ernande, Bruno; Boudry, Pierre. |
Among bivalve species, the Pacific oyster, Crassostrea gigas, is the most economically important bivalve production over the world. Today, C. gigas is subject to an important production effort that leads to an intensive artificial selection. Larval stage is relatively unknown, specifically in a domestication context. Genetic consequence of artificial selection is still at a preliminary study. We aimed to tackle the consequence of inconscient domestication on the variance reproductive success focusing on larval stage, keystone of the life cycle. We studied two kinds of specific selective processes that common hatchery rearing practices exert : the effect of discarding the smallest larvae on genetic diversity and the artificial environment rearing effect via... |
Tipo: Text |
Palavras-chave: Selection; Genetic correlations; Genetic variability; Genetic; Domestication selective; Crassostrea gigas; Pacific oysters. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3441.pdf |
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Boudry, Pierre; Degremont, Lionel; Taris, Nicolas; Mccombie, Helen; Haffray, Pierrick; Ernande, Bruno. |
To date, the most significant genetic improvement for the production of Pacific oyster (Crassostrea gigas) has been obtained through the breeding of triploids, especially since the development of tetraploids. Quantitative genetics studies suggest that significant gains, for disease resistance or for other traits of aquacultural interest, could be obtained in diploids using this approach. However, the limited extent of hatchery-propagation (versus natural recruitment) and/or various technical difficulties and biological characteristics of the species have retarded the development of selective breeding programs. Recently, in the U.S.A., Australia and New Zealand, countries where hatcheries are a major source of C. gigas juveniles, family-based selective... |
Tipo: Text |
Palavras-chave: Microsatellite markers; Selective breeding; Genetic; Genetic variability; Crassostrea gigas; Pacific oysters. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-3449.pdf |
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Boudry, Pierre; Collet, Bertrand; Cornette, Florence; Hervouet, Veronique; Bonhomme, Francois. |
Oysters, like many marine species have a very high fecundity. Previous studies have shown that populations, from both hatcheries and the natural environment, have very low Ne/N ratios. These observations reveal high variation in reproductive success. In order to study individual reproductive success under controlled conditions, we used microsatellite markers to quantify parental contributions in in vitro crosses (5 males and 5 females) of Crassostrea gigas, the Pacific oyster. High polymorphism of the microsatellites (more that 50 alleles per locus) eased the parentage identifications. The results of a cross allowing gametic competition were compared with the results from a second cross where the gametes of the same parents were kept separate for each... |
Tipo: Text |
Palavras-chave: Genetic; Hatchery; Microsatellite markers; Crassostrea gigas; Pacific oysters. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/acte-3457.pdf |
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Registros recuperados: 26 | |
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