Consulta: creatorFacets:"Samain, Jean-francois"
Registros recuperados: 65
Data/hora: 10/06/2024 05:48:57

Responses and adaptations of the adenylate energy charge and digestive enzyme activities to tidal emersion of Crassostrea gigas populations in Marennes-Oleron Bay
Provedor de dados: 5
Autores: Moal, Jeanne; Samain, Jean-francois; Le Coz, Jean-rene; Daniel, Jean-yves.
Crassostrea gigas oysters cultivated in Marennes-Oleron Bay (France), face seasonal variations in the environment: salinity, turbidity, phytoplanktonic production, and the tidal rhythm of emersion. The oysters are maintained at different depths to reduce competition for space (e.g. by settlement of mussel spat). The physiological responses of two groups of oysters to different periods of emersion were studied using a seasonal sampling strategy: one group was on a flat part of the area, and the effect of emersion was studied in a short time survey (less than three hours emersion at low tide); the other was located in a very narrow place with a steep slope. This group was subdivided into three, according to bathymetric position, to study the long term effect...
Tipo: Text
Palavras-chave: Crassostrea gigas; Physiology; Emersion; AEC; Digestive enzimes; Marennes-Oleron Bay.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00038/14885/12208.pdf

Effects of age and environment on the summer mortality in cupped oyster Crassostrea gigas during the first two years
Provedor de dados: 5
Autores: 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 survival 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 in mortality were observed during the first year in Riviere 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 groups,...
Tipo: Text
Palavras-chave: Crassostrea gigas; Spat; Spatial variations; Survival; Rearing; Mollusc culture; Marine molluscs; Environmental factors; Nursery grounds; Mortality causes; Biological age; Aquaculture techniques.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/acte-3385.pdf

Selective breeding to improve resistance against summer mortality in the Pacific oyster Crassostrea gigas : results after 3 generations
Provedor de dados: 5
Autores: Boudry, Pierre; Degremont, Lionel; Bedier, Edouard; Samain, Jean-francois.
Summer mortality of adults and juveniles has been reported in the Pacific oyster, Crassostrea gigas, for many years and in several countries. The French multidisciplinary program "Morest" aims to investigate the causes of the summer mortality in Crassostrea gigas. Within this program, we designed multi-site field experiments to assess to what extent genetic variability exists for summer mortality in French populations of C. gigas and to determine whether selective breeding could improve survival.
Tipo: Text
Palavras-chave: Growth; Resistance; Selective breeding; Genetic; Crassostrea gigas; Pacific oyster; Summer mortality.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/acte-3448.pdf

The identification of genes from the oyster Crassostrea gigas that are differentially expressed between progeny exhibiting opposed susceptibility to summer mortality
Provedor de dados: 5
Autores: 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

Genetic basis of summer mortality in juvenile cupped oysters
Provedor de dados: 5
Autores: Degremont, Lionel; Boudry, Pierre; Bedier, Edouard; Ropert, Michel; Soletchnik, Patrick; Huvet, Arnaud; Moal, Jeanne; Samain, Jean-francois.
The French project "Morest", coordinated by IFREMER, aims to understand the causes of the summer mortalities in Crassostrea gigas. In 2001, three sets of families were bred following a nested half-sib mating design. 17 half-sib families (HSF) were obtained in this first generation (G1) and reared in 3 sites. Significant differences in survival were observed among HSF, and some HSF showed high levels of mortality in all sites, clearly indicating a genetic basis for survival. In 2002, a second generation (G2), including divergent selection and inbred lines, was constituted. Monitoring of survival and growth of G2s were the same as in 2001. Significant differences in survival were found between the offspring of the "high" and "low" selected groups and between...
Tipo: Text
Palavras-chave: Summer; Oyster culture; Juveniles mortality; Genetics; Commercial species; Breeding.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3346.pdf

Effect of age and environment on the summer mortality in cupped oyster Crassostrea gigas during the first two years
Provedor de dados: 5
Autores: 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

Lipid requirements of the scallop Pecten maximus (L.) during larval and post-larval development in relation to addition of Rhodomonas sauna in diet
Provedor de dados: 5
Autores: Gagne, Renee; Tremblay, Rejean; Pernet, Fabrice; Miner, Philippe; Samain, Jean-francois; Olivier, Frederic.
The main objective of this study was to evaluate the effect of the addition of Rhodomonas salina in the diet of Pecten maximus on growth, survival and metamorphosis success in relation to biochemical content. Food quality is an essential factor in the success of larval, post-larval and juvenile development. A diet rich in polyunsaturated fatty acids present an advantage for growth, survival and metamorphosis success. Larvae and post-larvae fed with the diet containing R. sauna showed a higher accumulation of arachidonic acid (20:4n-6) and generally a lower concentration of docosahexaenoic acid (22:6n-3). Addition of R. sauna in diet was related with higher level of eicosapentaenoic acid (20:5n-3) in larval stages, but lower level in post-larvae. Addition...
Tipo: Text
Palavras-chave: Nutrition; Biochemical characteristics; Fatty acids; Sterol profiles.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00019/13045/10205.pdf

Starch supplementation modulates amylase enzymatic properties and amylase B mRNA level in the digestive gland of the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Huvet, Arnaud; Jeffroy, Fanny; Daniel, Jean-yves; Quere, Claudie; Le Souchu, Pierrick; Van Wormhoudt, A.; Boudry, Pierre; Moal, Jeanne; Samain, Jean-francois.
In the oyster Crassostrea gigas consumption-related traits, amylase properties and growth were found to be linked through genotypes that differed for polymorphism in the two amylase genes AMYA and AMYB. Modulation of AMYA mRNA level had already been observed in response to food availability, whereas the functional role of AMYB was still unknown. To improve knowledge about the regulation of amylase expression in C. gigas and the respective roles of the two genes, we made an assay of amylase expression at mRNA and enzymatic levels in the digestive gland of oysters that had received dietary supplements of starch. After 18 days, a significant increase of translatable mRNA for AMYB was observed, with a correlated increase in Michaelis-Menten constant Km values...
Tipo: Text
Palavras-chave: Alpha-amylase; Crassostrea gigas; Digestive enzyme; Michaelis-Menten constant; Regulation.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00087/19869/17521.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

Characterization of summer mortalities of C. gigas oyster in France in relation to environmental parameters
Provedor de dados: 5
Autores: Soletchnik, Patrick; Ropert, Michel; Bedier, Edouard; Costil, K. S.; Dubois, Brice; Degremont, Lionel; Bouget, Jean-francois; Martin, Jean-louis; Enriquez-diaz, M.; Faury, Nicole; Le Moine, Olivier; Renault, Tristan; Gagnaire, Beatrice; Huvet, Arnaud; Moal, Jeanne; Samain, Jean-francois.
Field characterization of summer mortality was performed in France in the frame of the Morest project. Natural and hatchery spat were compared between three oyster production areas in France. Regardless of the natural or hatchery origin, oysters died during the reproduction period after temperature reaches 19 degree C. Thus, in southern areas, temperature accelerated gametogenesis of small spat (10mm) as well as adults, and mortality appeared for the two age classes. In contrast, sexual maturation proceeded more slowly in northern where spat mortality was lower compared to 18 months old oysters. However, critical gametogenesis and temperature were not sufficient to induce mortalities, as observed in examples with stable environment. Alternatively sediment...
Tipo: Text
Palavras-chave: Seasonal variation; Oyster culture; Mortality causes; Hatcheries; Gametogenesis; Environmental factors; Crassostrea gigas; Oysters.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3348.pdf

Techniques for delivery of arachidonic acid to Pacific oyster, Crassostrea gigas, spat
Provedor de dados: 5
Autores: Seguineau, Catherine; Soudant, P; Moal, Jeanne; Delaporte, Maryse; Miner, Philippe; Quere, Claudie; Samain, Jean-francois.
The present study tested two techniques for dietary supplementation of Crassostrea gigas spat with PUFA, such as arachidonic acid (AA). The first technique consisted of a preliminary enrichment and growth of an algal concentrate (T-ISO, Isochrysis sp.) with AA dissolved in an ethanol solution, the whole culture then being fed to the spat. This enrichment increased the AA weight percentage in T-ISO neutral and polar lipids from 0.6 to 22.4% and from 0.4 to 6.8%, respectively. The second delivery technique was direct addition separately of free AA dissolved in ethanol solution and algal concentrate (T-ISO + AA) to the spat-rearing tank. To test the efficiency of these delivery techniques, oyster spat were supplemented with AA-enriched T-ISO, T-ISO + AA, and...
Tipo: Text
Palavras-chave: Food supply; Arachidonic acid; Spat; Crassostrea gigas; Dietary.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-1094.pdf

Modèle de détection rapide des effets sublétaux des polluants. II. Un exemple in situ : anomalie métabolique de copépode hyponeustonique Anomalocera patersoni en coïncidence avec une marée noire
Provedor de dados: 5
Autores: Samain, Jean-francois; Moal, Jeanne; Alayse-danet, Anne-marie; Daniel, Jean-yves; Le Coz, Jean-rene.
Model for Rapid Detection of Sublethal Effects of Pollutants. II. An in situ Example: Anomalous Metabolism of the Hyponeustonic Copepod Anomalocera patersoni Coinciding with an Oil Spill An unusual correlation has been obsemed between the amylase and trypsin content of a natural zooplankton population and of the hyponeustonic copepod Anomalocera patersoni and the oil spill of the "Amoco Cadiz" in 1978.  This anomaly has also been obsewed in Artemia sp. cultures (San Francisco Bay strain) poisoned by copper. This phenomenon could originate from a general physiological perturbation.  Such a non-specific perturbation could explain the anormal correlation between parameters which are usually independent and specifically regulated.  The determination of such...
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-5362.pdf

Ecologie bacterienne dans les bacs d'elevage larvaire de coquilles Saint-Jacques (Pecten maximus )
Provedor de dados: 5
Autores: Jacq, E; Moal, Jeanne; Samain, Jean-francois; Corre, S; Daniel, J; Nicolas, Jean-louis; Cochard, Jean-claude; Fera, P.
Larval rearings were performed with seawater either freshly pumped or after storage in a pond. Concerning bacterial populations these waters were characterized by a high diversity, little sized bacteria whose few of them (1%) were cultivable on Zobell medium. In the tanks, the bacterial ecosystem was modified by the presence of antibiotics, larvae and algae: the diversity was lowered, the cellular volume was increased by a factor 2 to 5, 100% bacteria were cultivable and chloramphenicol resistant, and their metabolism changed. Taxonomic screening showed no differences among the two waters neither at the beginning nor at the end of the rearings. However, depending on the water (stored or not) differences were identified for bacterial physiology and...
Tipo: Text
Palavras-chave: Marine aquaculture; Pond culture; Scallop culture; Ecology; Antibiotics; Organic matter; Grazing; Carbohydrates; Mathematical models; Modelling; Growth; Bacterial diseases; Biological production; Culture tanks; Larvae; Rearing.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/1992/acte-914.pdf

Lipid composition of the giant lion's-paw scallop (Nodipecten subnodosus) in relation to gametogenesis - I. Fatty acids
Provedor de dados: 5
Autores: Palacios, Elena; Racotta, I; Kraffe, E; Marty, Y; Moal, Jeanne; Samain, Jean-francois.
Seasonal variations in fatty acid composition in several tissues of a 1-year-old population of giant lion's-paw scallop Nodipecten subnodosus were analyzed during gonad development. Samples were taken bimonthly from December 1999 to June 2000, a period in which gonad development was occurring. Fatty acid accumulation in neutral and polar lipids of the female gonad was concomitant to the gonad development and presented a maximum in June. Among essential fatty acids, a specific accumulation was observed only for 20:5n - 3 in the female gonad, as suggested by an increase in its proportion in the neutral and the polar fractions. However, no specific accumulation was observed for 22:6n - 3, as its proportion remained relatively constant in both fractions. We...
Tipo: Text
Palavras-chave: Reproduction; Pectinidae; HUFA; EPA; DHA; Arachidonic acid.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-767.pdf

Hemocyte characteristics in families of oysters, Crassostrea gigas, selected for differential survival during summer and reared in three sites
Provedor de dados: 5
Autores: Lambert, Christophe; Soudant, Phillippe; Degremont, Lionel; Delaporte, Maryse; Moal, Jeanne; Boudry, Pierre; Jean, Frédéric; Huvet, Arnaud; Samain, Jean-francois.
High variability among individuals is often encountered when hemocyte characteristics are measured in bivalves. Such variability is suspected to result partly from genetic factors. In this study, hemocyte characteristics of six families of Crassostrea gigas were compared by flow cytometry at one sampling date in October 2001. These families were obtained from a nested, half-sibling cross design, and reared from July to October 2001 at three sites distributed along the French Atlantic coast from north to south: Baie des Veys (Normandy), Riviere d'Auray (Brittany) and Ronce (Marennes-oleron Basin, Poitou Charentes).   Among the 15 measured hemocyte characteristics, production of reactive oxygen species (ROS) of untreated hemocytes (maintained in filtered...
Tipo: Text
Palavras-chave: Genetic; Flow cytometry; Reactive oxygen species ROS; Adhesion; Hemocyte; Crassostrea gigas; Summer mortality.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3054.pdf

Effect of sediment nearness on the metabolic enzyme activity and energy state of the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Le Moullac, Gilles; Fleury, Pierre-gildas; Le Coz, Jean-rene; Moal, Jeanne; Samain, Jean-francois.
This study was designed to assess in situ the effects of sediment nearness on Crassostrea gigas metabolism. One year-old oysters were reared for 5 months (April-August) in plastic bags on metallic frames at 10 and 60 cm off the sediment at the beginning of April. The management of the energetic resources (storage, consumption) was estimated with respect to biochemical changes of proteins, lipids and carbohydrates. In order to evaluate the  effect of the sediment nearness at cellular level, the metabolic rate was evaluated by assessing pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK) enzyme activities and electron transport system (ETS) activity. The metabolic pathways were assessed by measuring ATP and intermediary metabolites such as...
Tipo: Text
Palavras-chave: Aspartate; Succinate; Alanine; ETS; PEPCK; PK; Carbohydrate; Lipids; Proteins; Sediment; Oyster; Aspartate; Succinate; Alanine; ETS; PEPCK; PK; Glucides; Lipides; Proteines; Sédiment; Huître.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2803.pdf

Etude du polymorphisme des gènes de l'amylase chez Crassostrea gigas : relation avec les paramètres physiologiques de l'assimilation et croissance
Provedor de dados: 5
Autores: Degremont, Lionel; Moal, Jeanne; Daniel, Jean-yves; Boudry, Pierre; Van Vormhoudt, A.; Sellos, D.; Samain, Jean-francois.
In the scope of the European program GENEPHYS, which aims to establish the relationship between the genetic base and the physiological characters in relation to the growth in Crassostrea gigas, it has been demonstrated that the most explanatory factors for the growth variability are assimilation performance and aneuploidy. A model linking the assimilation performances and the digestive equipment has been set up and more than 70% of the variability can be explained by two digestive enzymes: laminarinase and amylase. A number of laboratories have decided to focus on the latter.
Tipo: Text
Palavras-chave: Croissance; Génétique; Polymorphisme; Crassostrea gigas.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3269.pdf

Possible processes of nutritive adaptations for zooplankton : a demonstration on Artemia
Provedor de dados: 5
Autores: Samain, Jean-francois; Moal, Jeanne; Daniel, Jean-yves; Le Coz, Jean-rene.
The ingestion rate and the resulting assimilation calculated by means of a law taking into account activities of the digestive enzymes (amylase and trypsin) on the carbohydrates and proteins ingested, are determined in two experiments on Artemia. They are fed the same species of phytoplankton (Tetraselmis suecica), at the same concentration but with two chemical compositions. In one experiment, the cells are rich in carbohydrates and poor in proteins, and in the second one they are poor in carbohydrates, rich in proteins.  Different observed ingestion rates induce a balance in proteins, and a large difference in the carbohydrates ingested. When digestive enzymes are taken into account, the assimilated carbohydrates and proteins are similar (explaining the...
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-5360.pdf

Signification biologique des teneurs protéiques et des activités de l'amylase et des protéases chez Artemia salina L. aspects d'application a l'étude de la nutrition
Provedor de dados: 5
Autores: Samain, Jean-francois; Boucher, Jean; Buestel, Dominique; Borne, M.; Le Coz, Jean-rene.
The relations between the activity of the digestive enzymes amylase and proteases were studied on Artemia salina L. For this purpose, a method for measuring the ingestion was developed compatible with the speed of response of the digestive enzymes. It is demonstrated that the proteic density variations in Artemia of the same size are in relation to the food content of their digestive tract. Therefore the measurement of the size and weight of proteins (proteic density) allows the evaluation of the ingestion. With the aid of this method, a daily ingestion rhythm, with bimodal character, could be demonstrated. The influence on the ingestion, of the concentration of food available (Tetraselmis suecica Butcher) was studied in function of the size of the...
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1975
URL: http://archimer.ifremer.fr/doc/1975/publication-5104.pdf

Oyster adenytate energy charge: response to levels of food
Provedor de dados: 5
Autores: Moal, Jeanne; Le Coz, Jean-rene; Samain, Jean-francois; Daniel, Jean-yves; Bodoy, Alain.
Adenylatc Encrgy Charge (AEC) values of Crassostrea gigas (9 and 18 months old) cultured in ponds in Marennes-Oléron Bay (Atlantic coast, France) are reported. Two ponds were loaded with two different initial oyster biomasses in order to obtain different food conditions. The growth of oysters was different in the two ponds which corroborated the effectivences of attaining different food conditions. AEC level was different depending on the pond and was therefore related to food availability per unit oyster biomass. Well-fed oysters exhibited greater AEC values than poorly-fed oysters, throughout thc study. Information on nutritional situations for wild or cultured populations can therefore be obtained by AEC. In cach pond, the seasonal AEC variations were...
Tipo: Text
Palavras-chave: Charge énergétique adénylique; Crassostrea gigas; Nutrition; Nucléotides; Adenylate energy charge; Crassostrea gigas; Food; Nucleotides.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00038/14882/12202.pdf

Dosage automatique et simultané de l'amylase et des protéines du zooplancton
Provedor de dados: 5
Autores: Samain, Jean-francois; Boucher, Jean.
A method for nutrition, production and ecological studies by calculation of amylase specific activity of zooplankton is described. The method's adjustment is based on the biochemical properties of the enzyme. The activity measurement of a single Artemia salina, a few Copepods, or of the whole contents of a net is possible with 5 % accuracy. Up to 15 samples can be analysed within one hour with good reproducible results. The method is well suited to in situ studies aboard oceanographic vessels. [NOT CONTROLLED OCR]
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1974
URL: http://archimer.ifremer.fr/doc/1974/publication-5424.pdf

Changes in biochemical and hemocyte parameters of the pacific oysters Crassostrea gigas fed T-Iso supplemented with lipid emulsions rich in eicosapentaenoic acid
Provedor de dados: 5
Autores: Delaporte, Maryse; Chu, Fu-lin; Langdon, Chris; Moal, Jeanne; Lambert, Christophe; Samain, Jean-francois; Soudant, Philippe.
The aim of this study was to assess the effect of dietary eicosapentaenoic acid (20:5n-3) on hemocyte parameters such as hemocyte concentration, phagocytosis, and non-stimulated reactive oxygen species (ROS) production in Pacific oysters Crassostrea gigas, as well on proximate biochemical and fatty acid compositions. One-year-old oysters (C. gigas) were fed T-Isochrysis aff. galbana(T-Iso), which is low in 20:5n-3, either alone or with supplements of a lipid emulsion rich in 20:5n-3 at 1%, 10% or 50% (dry weight of the algal ration) for up to 7 weeks. Changes in gill fatty acid composition demonstrated that the lipid emulsion was well ingested by oysters during the dietary conditioning. Biochemical analysis indicated that oysters fed supplements of 50%...
Tipo: Text
Palavras-chave: Polyunsaturated fatty acids; Immunology; Hemocytes; Eicosapentaenoic acid 20 : 5n 3; Crassostrea gigas; Bivalves.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2604.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

Genetic bases and variability of physiological traits involved in growth in Crassostrea gigas - Third Progress Report 1st January-31st December 1998 - Contract N°FAIR 95-421 Commission of the European Communities
Provedor de dados: 5
Autores: Gerard, Andre; Boudry, Pierre; Bougrier, Serge; Buestel, Dominique; Samain, Jean-francois; Hawkins, A. J. S.; Wilins, N.; Zouros, Eleftherios; Bonhomme, Francois; Thiriot Quievreux, Catherine.
The EU project "GENEPHYS", initiated by the IFREMER laboratory GAP-La Tremblade (Génétique Aquaculture et Pathologie) and CREMA-l'Houmeau (Centre de Recherche en Ecologie Marine et Aquaculture), aims to establish the relationships between physiological traits involved in growth (oxygen consumption, absorption efficiency, scope for growth) and their genetic bases (determinism, variability within and among populations) in cupped oyster Crassostrea gigas. The main bjectives are : 1. To express the maximum variability of growth, both at the larval stage and at the adult stage, in a oyster population originating from parents of various origins. 2. To check the persistence over the time, of growth performance and related physiological functions. 3. To explain...
Tipo: Text
Palavras-chave: Genetic; Determinism; Variability; Physilogy; Oxygen consumption; Growth; Absorption efficiency; Oysters; Crassostrea gigas.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00050/16151/13634.pdf

Etude de la nutrition, du régime et du rythme alimentaire du zooplancton dans les conditions naturelles, par la mesure des activités enzymatiques digestives
Provedor de dados: 5
Autores: Boucher, Jean; Laurec, Alain; Samain, Jean-francois; Smith, S. L.
The amylase and trypsin activity of the most important zooplankton species has been measured in the upwelling zone of the Spanish Sahara during the "Gibraltar ecophysiological cruise" of the oceanographic vessel Jean Charcot. The analysis of the results was carried out for the double purpose of demonstrating the regulation by the nutrition of the activities of digestive enzymes and utilizing these results to study the feeding behavior under the natural environmental conditions of an ecosystem.  With regard to its biological significance, the influence of the quality and quantity of food available has been demonstrated by a bouble experimental approach followed by a statistical one. Significant correlations were found between the specific amylase activity...
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1975
URL: http://archimer.ifremer.fr/doc/1975/publication-5105.pdf

Activités amylasique et trypsique du zooplancton-indices de nutrition ? perspectives et limites
Provedor de dados: 5
Autores: Samain, Jean-francois; Moal, Jeanne.
The regulation of the synthesis of the digestive enzymes of the zooplankton and the brine shrimp (amylase and trypsine activity) has been studied to find some nutrition indexes enabling the description of the zooplankton's nutritive activity in situ. These regulations lead us to tackle three domains of pelagic ecology:- The evaluation of the organisms' nutrive needs and the capacity of the environment to satisfy them.- The monitoring of the pelagic ecosystem- The disturbance of the ecosystems.
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-5972.pdf

Mortalités estivales et croissance du naissain de l'huître creuse Crassostrea gigas : étude de familles sélectionnées
Provedor de dados: 5
Autores: Degremont, Lionel; Boudry, Pierre; Bedier, Edouard; Ropert, Michel; Soletchnik, Patrick; Huvet, Arnaud; Moal, Jeanne; Samain, Jean-francois.
In the scope of the Morest program, 3 series of bi-parental families of cupped oyster consisting of full and half-sib have been created in 2001, and then studied on a regular basis on several sites over the summer period. In October, major survival differences had been demonstrated between the 3 families. The average survival rate for the half-sib families monitored on the three sites varies from 17 to 97 %. Some of them showed high mortality for the three sites, indicating a strong genetic basis (h2 = 0.81 - 0.29) to the variations observed regarding survival. To a lesser extent, growth differences between the studied half-sib families indicate a weaker heritability for this character. ....
Tipo: Text
Palavras-chave: Physiologie; Génétique; Naissain; Sélection; Croissance; Survie; Huîtres; Crassostrea gigas.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3490.pdf

Summer mortality in juvenile cupped oysters : response to selection in the field and in laboratory
Provedor de dados: 5
Autores: 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 &amp;#61617; 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

Review and perspectives of physiological mechanisms underlying genetically-based resistance of the Pacific oyster Crassostrea gigas to summer mortality
Provedor de dados: 5
Autores: Samain, Jean-francois.
French oyster farming has been subject to severe mortalities during the summer months. Results from the research program "Morest", which ran from 2000 to 2006 and examined the possible causes of these mortalities, led to the construction of a model to explain the interaction between environmental factors, oyster physiology and different opportunistic pathogens underlying oyster summer mortality. Temperature, food, reproduction and stress were the main factors required for oyster mortality. Genetically-based resistance ("R" oysters) or susceptibility ("S" oysters) to summer mortality was revealed by divergent selection. Building on these results, a literature search was made in 2007 on the molecular origin of genetic resistance to such a complex mortality...
Tipo: Text
Palavras-chave: Immunity; Antibacterial activity; Host defence; Environmental stress; Crassostrea gigas.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00051/16229/13752.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

C/N et contrôle de la physiologie des cultures de phytoplancton
Provedor de dados: 5
Autores: Moal, Jeanne; Samain, Jean-francois; Le Coz, Jean-rene.
Nutrients can be used for induction of carbohydrate or protein metabolism of three unicellular algae, their chemical variations measured by c/N ratio. The C/N determination and evolution can be used as a control for growth phase and satured conditions. Cultures of routine production have been tested by such a method. The results are discussed. [NOT CONTROLLED OCR]
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/1979/publication-5221.pdf

In vitro modulation of reactive oxygen and nitrogen intermediate (ROI/RNI) production in Crassostrea gigas hemocytes
Provedor de dados: 5
Autores: Lambert, Christophe; Soudant, Philippe; Jegaden, Marine; Delaporte, Maryse; Labreuche, Yannick; Moal, Jeanne; Samain, Jean-francois.
Bivalve hemocyte competence has been measured by quantifying functional characteristics, including reactive oxygen intermediate (ROI) production after activation with zymosan or phorbol myristate acetate (PMA). However, untreated oyster hemocytes also produce ROI and RNI (reactive nitrogen intermediates) after bleeding even if not stimulated by Zymosan or PMA. Extensive investigation of this parameter by flow cytometry showed that, in vitro, ROI/RNI production by untreated hemocytes maintained in seawater appeared to be independent of both bacterial burden in the serum and non-self particle phagocytosis. ROI/ RNI production in granulocytes was higher than in hyalinocytes and could be intensified when activated by zymosan but not by PMA. Both cell types...
Tipo: Text
Palavras-chave: NO synthase; NADPH oxidase; Flow cytometry; Reactive nitrogen intermediate RNI; Reactive oxygen intermediate ROI; Hemocytes; Crassostrea gigas.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3057.pdf

Effet de la qualité de l'eau sur la croissance larvaire de Pecten maximus en écloserie : observations préliminaires
Provedor de dados: 5
Autores: Samain, Jean-francois; Cochard, Jean-claude; Chevolot, Lionel; Daniel, Jean-yves; Jeanthon, C.; Le Coz, Jean-rene; Marty, Y.; Moal, Jeanne; Prieur, D.; Salaun, Michele.
Some positive growth differences can be observed, all year long, in Pecten maximus larvae cultivated in an old fishpond, compared with the water which flows into it periodically. These waters are filtered at 1 µm through CUNO cartridges. Moreover, the larvae are cultivated in the same light, temperature and food (cultured phytoplankton) conditions. This difference is significant in terms of larvae size, dry weight, organic matter, ashes, total proteins, glycogen, and lipids. A series of preliminary observations on the chemical composition of these two waters after filtration (amino acids, fatty acids, organic mater, nutritive salts), on the bacterial flora (total, heterotrophic organisms, vibrio), on the particular material using electron microscopy, on...
Tipo: Text
Palavras-chave: Larve; Ecloserie; Pecten maximus; Facteur croissance; Qualité eau.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/acte-6185.PDF

Genetic bases and variability of physiological traits involved in growth in Crassostrea gigas - Second Progress Report 1st January-31st December 1997 - Contract n° FAIR 95-421 Commission of the European Communities
Provedor de dados: 5
Autores: Gerard, Andre; Boudry, Pierre; Bougrier, Serge; Hawkins, A. J. S.; Thiriot Quievreux, Catherine; Wilkins, N. P.; Zouros, Eleftherios; Bonhomme, Francois; Buestel, Dominique; Samain, Jean-francois.
The UE project "GENEPHYS", initiated by the IFREMER laboratory GAP-La Tremblade (Génétique Aquaculture et Pathologie) and CREMA-L'Houmeau (Centre de Recherche en Ecologie marine et Aquaculture), aims to establish the relationships between physiological traits involved in growth (oxygen consumption, absorption efficiency, scope for growth) and their genetic bases (determinism, variability within and among populations) in cupped oyster Crassostrea gigas. The main objectives are : 1. To express the maximum variability of growth, both at the larval stage and at the adult stage, in a oyster population originating from parents of various origins. 2. To check the persistence over the time, of growth performance and related physiological functions. 3. To explain...
Tipo: Text
Palavras-chave: Genetic; Determinism; Variability; Physilogy; Oxygen consumption; Absorption efficiency; Growth; Oysters; Crassostrea gigas.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00050/16150/13633.pdf

Etude de la nutrition du zooplancton en zone d'upwelling par la mesure des activités enzymatiques digestives
Provedor de dados: 5
Autores: Boucher, Jean; Samain, Jean-francois.
The feeding of the zooplankton has been studied in the natural environment of an upwelling ecosystem by measurements of amylase and protease activities. The hypothesis of enzymatic specific activity as a nutritional index is extended by a correlation with Lorenzen's grazing index. There is no correlation between amylase and protease activity so the diet of the populations is described by the ratio of these two enzymatic activities. Variations of relative feeding rate for Calanus, Temora, Acartia, Podon, and for the total sample are discussed in relation to the ecological and trophic characteristics of the environment.
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1975
URL: http://archimer.ifremer.fr/doc/1975/publication-5463.pdf

Effects of age and environment on survival of summer mortality by two selected groups of the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Degremont, Lionel; Boudry, Pierre; Ropert, Michel; Samain, Jean-francois; Bedier, Edouard; Soletchnik, Patrick.
This study investigated the effects of age (first or second summer of life) and environment (three study sites on French coasts) on summer mortality in Crassostrea gigas, using three generations of oysters produced during the Morest project. For each generation, two groups of oysters, selected either as 'resistant' (R) or 'susceptible' (S) to summer mortality at the age of 6 months in Rivière d'Auray (RA, South Brittany), were evaluated. In Ronce (Marennes-Oléron Bay) and RA, R oysters had low mortality during their first and second summers, while mortality was higher during the second summer in Baie des Veys (BDV, Normandy). In RA, S oysters exhibited higher mortality during their first summer than during their second, while the opposite result was found...
Tipo: Text
Palavras-chave: Summer mortality; Age; Environment; Genetic; Crassostrea gigas.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/2009/publication-6972.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

Activités amylasique et trypsique des principales espèces de poissons de l'estuaire interne de la Loire en relation avec l'environnement trophique
Provedor de dados: 5
Autores: Marchand, J.; Samain, Jean-francois.
Quantitative and qualitative relations between the activity of the digestive enzymes (amylase and trypsin) and the nutrition of young fishes of five species (bass, whiting pout, sole, flounder and mugil) of the Loire estuary are analyzed.
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-5973.pdf

L'activité amylasique indice de la nutrition de zooplancton ; mise en évidence d'un rythme quotidien en zone d'upwelling
Provedor de dados: 5
Autores: Boucher, Jean; Samain, Jean-francois.
Specific amylase activity was measured during the CINECA III cruise in the moroccan upwelling area. In this region the population is homogeneous and in a steady state during the study.  The hypothesis of enzymatic activity rate as a nutrition index is enlarged by a relation with diet, fast and feeding stock. A mathematical expression is given of the relationship between zooplankton digestive activity and phytoplankton biomass. Analysis of this equation shows a daily physiological rhythm of the amylase activity. [NOT CONTROLLED OCR]
Tipo: Text
Palavras-chave: Histoire Ifremer.
Ano: 1974
URL: http://archimer.ifremer.fr/doc/1974/publication-5149.pdf

Réponses et adaptations de la charge énergétique adénylique et l'activité enzymatique digestive à l'emersion chez Crassostrea gigas
Provedor de dados: 5
Autores: Moal, Jeanne; Samain, Jean-francois.
The effect of tidal emergence on the adenylate energy charge value was studied in Crassostrea gigas oysters in Marennes-Oleron Bay. The shot-term AEC responses to aerial exposure differed according to the period of the year. However, on a long-term basis, osters from three bathymetric positions exhibited the same AEC value, but had a different growth rate. The amylase increase observed for the most emerged oysters may play a role in the maintenance of energy equilibrium.
Tipo: Text
Palavras-chave: Charge énergétique; Amylase; Emersion; Huîtres; Crassostrea gigas; Cycle de marée; ATP; Adenylic energy charge; Amylase; Emersion; Oysters; Crassostrea gigas; Tidal cycle.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/00022/13285/10331.pdf

Recent advances in EST sequencing in Crassostrea gigas: towards the sequencing of the Pacific oyster genome
Provedor de dados: 5
Autores: Boudry, Pierre; Huvet, Arnaud; Lapegue, Sylvie; Sauvage, Christopher; Tanguy, A.; Moraga, D.; Goostrey, A.; Prunet, P.; Boulo, Viviane; Gueguen, Y.; Moal, Jeanne; Fleury, Elodie; Samain, Jean-francois; Mathieu, M.; Favrel, P.
Rationale for EST and genome sequencing of the Pacific oyster: • its membership of the Lophotrochozoa, an little studied branch of the Eukaryotes, • its worldwide aquacultural importance (4.2 million metric tons, worth 3.5 billion US dollars), • its high fecundity, with concomitantly high DNA polymorphism, • its use as a biosensor of coastal pollution. In 2004, an international community of biologists, the Oyster Genome Consortium (OGC) led by D. Hedgecock (University of Southern California) and uniting 70 participants from 10 countries, first presented the Pacific oyster Crassostrea gigas as a genome-sequencing candidate to Joint Genome Institute (JGI, USA) (Hedgecock et al., 2005). Besides this project (that remains to be accepted), several EST...
Tipo: Text
Palavras-chave: Characteristics; Genome size; Genome; Crassostrea gigas; Oyster; Genetic.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/acte-3414.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

Effect of Rhodomonas salina addition to a standard hatchery diet during the early ontogeny of the scallop Pecten maximus
Provedor de dados: 5
Autores: Tremblay, Rejean; Cartier, Simon; Miner, Philippe; Pernet, Fabrice; Quere, Claudie; Moal, Jeanne; Muzellec, Marie-louise; Mazuret, Michel; Samain, Jean-francois.
The main objective of this study was to identify algal diets that maximize the survival and growth and alter the biochemical content of Pecten maximus larvae with the aim of improving metamorphosis. We also evaluated the potential of the cryptophyceae Rhodomonas salina as a food source for these larvae. Two flagellates, Isochrysis aff. galbana (T) and Pavlova lutheri (P), and two diatoms, Chaetoceros gracilis (C) or Skeletonema costatum (S), were tested as two ternary diets, namely PTC and PTS. PTC and PTS were compared with diets that also included R. salina (R). The addition of R. salina and the replacement of C. gracilis by S. costatum in the traditional hatchery diet seem to be two interesting alternatives for increasing the productivity of larval...
Tipo: Text
Palavras-chave: Algal fatty acids and sterols; Energetic content; Metamorphosis; Nutrition; Scallop.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2404.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

Amylase polymorphism affects growth in the cupped oyster Crassostrea gigas
Provedor de dados: 5
Autores: Huvet, Arnaud; Samain, Jean-francois; Boudry, Pierre; Bedier, Edouard; Ropert, Michel; Van Wormhoudt, A.
The better understanding of physiological and environmental factors that determine optimal food conversion efficiencies is of major interest for the cupped oyster Crassostrea gigas for which the strong increase of aquaculture has been correlated in France with a decrease in productivity due to competition between aquatic species for limited food supplies at grow-out sites. To investigate the non-neutrality of the polymorphism of amylase, a key enzyme for carbohydrate assimilation, in oyster physiology, we report in the present paper the growth and survival measurement of amylase genotypes within five bi-parental C. gigas families, bred to be polymorph at the two PCR-RFLP amylase markers, and reared over one year under standard culture conditions in two...
Tipo: Text
Palavras-chave: Amylase markers; Growth; Amylase Polymorphism; Genetic; Oysters; Crassostrea gigas.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/acte-3311.pdf

The identification of genes from the oyster Crassostrea gigas that are differentially expressed in progeny exhibiting opposed susceptibility to summer mortality
Provedor de dados: 5
Autores: Huvet, Arnaud; Herpin, Amaury; Degremont, Lionel; Labreuche, Yannick; Samain, Jean-francois; Cunningham, Charles.
Summer mortality associated with juveniles of the oyster Crassostrea gigas is probably the result of a complex interaction between the host, pathogens and environmental factors. Genetic variability in the host appears to be a major determinant in its sensitivity to summer mortality. Previously, divergent selection criteria based on summer survival have been applied to produce oyster families with resistant and susceptible progeny. In this paper, we describe the use of suppression subtractive hybridization to generate 150 C gigas clones that were differentially regulated between resistant and susceptible F2 progeny. The nucleotide sequence of these clones was determined. In 28%, the inferred amino sequence was found to match the products of known genes, 14%...
Tipo: Text
Palavras-chave: Suppression subtractive hybridization; Oysters; Differentially regulated genes; Bivalves; Bacterial challenge.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-651.pdf

Relative importance of family, site, and field placement timing on survival, growth, and yield of hatchery-produced Pacific oyster spat (Crassostrea gigas)
Provedor de dados: 5
Autores: Degremont, Lionel; Bedier, Edouard; Soletchnik, Patrick; Ropert, Michel; Huvet, Arnaud; Moal, Jeanne; Samain, Jean-francois; Boudry, Pierre.
Summer mortality has been reported in the Pacific oyster, Crassostrea gigas, for many years in different parts of the world. The causes of this phenomenon are complex. The multidisciplinary program "MOREST", coordinated by IFREMER, was initiated to understand the causes of summer mortality of Crassostrea gigas juveniles in France and to reduce its impact on oyster production. Within this program, three successive groups of bi-parental families were bred in a hatchery in 2001 and placed in the field during summer in three sites (Ronce, Riviere d'Auray, and Baie des Veys). This paper reports the relative importance of family, site and field placement timing for three characters of major importance for oyster production: survival, growth, and yield. At the...
Tipo: Text
Palavras-chave: Juvenile; Crassostrea gigas; Oysters; Yield; Growth; Survival.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-1693.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

Free amino-acids in copepod fecal pellets
Provedor de dados: 5
Autores: Poulet, Sa; Harris, Rp; Martin-jezequel, Veronique; Moal, Jeanne; Samain, Jean-francois.
By measuring water soluble extracts of free amino acids (DF AA) in the diets and faecal pellets of copepods using high performance liquid chromatography (HPLC), it was found that the molar composition of these molecules in the faeces produced depends on the type of food selected and reflects the hydrolysis of food proteins during digestion. On average, four amino acids (ASP, SER, GLY and LEU) together accounted for 63% of total DF AA in the faecal pellets of a variety of copepod species. The diversity of DFAA in copepod faecal pellets was higher than in sea water or in particles and phytoplankton cells ingested by copepods. These first results on DFAA in copepod faecal material indicate the importance of zooplankton faeces in the flux of dissolved nitrogen...
Tipo: Text
Palavras-chave: Acides aminés; Copépodes; Fécès; Ammo acids; Copepods; Faeces.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00111/22269/19944.pdf

Genetic polymorphism of glutamine synthetase and delta-9 desaturase in families of Pacific oyster Crassostrea gigas and susceptibility to summer mortality
Provedor de dados: 5
Autores: David, Elise; Boudry, Pierre; Degremont, Lionel; Tanguy, Amelie; Quere, N; Samain, Jean-francois; Moraga, D.
Large-scale mortality events have been observed in Pacific oyster Crassostrea gigas on the west coast of France since the early 1980s, particularly during summer. In order to understand the causes of this mortality, two generations of oysters from single-pair matings were studied in three sites on the French Atlantic coast (Baie-des-Veys, Auray and Ronce-les-Bains). The present paper examines the role of two candidate genes in the susceptibility of oysters to summer mortality, and the selective pressure exerted by such mortality on their polymorphism. Glutamine synthetase (amino-acid metabolism) and delta-9 desaturase (lipid metabolism) genes were studied in the successive generations, using polymerase chain reaction single-strand conformation polymorphism...
Tipo: Text
Palavras-chave: SSCP; Mortality; Glutamine synthetase; Delta 9 desaturase; Crassostrea gigas.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3040.pdf

Evolution de la biomasse et de la physiologie du zooplancton sur la côte nord de Bretagne en relation avec l'échouage de l'Amoco Cadiz : résultats préliminaires pour la période du 16 mars au 20 mai 1978
Provedor de dados: 5
Autores: Samain, Jean-francois; Le Fevre, J.; Moal, J.; Daniel, J.y.; Boucher, Jean.
First results about distribution and changes of biomass (dry weight and total soluble proteins), physiology (amylase, trypsin) and faunistic composition of zooplankton are reported for the two months period following the spill of AMOCO CADIZ on the Britany Northern coast. A shortage of biomass in the aber area is attributed to hydrocarbons. The low level of the mean value of biomasse on the North coasts, and the pecularities of estuarine station of the Lannion bay and of Trieux area are reported and discussed.
Tipo: Text
Palavras-chave: Amoco Cadiz; Zooplancton; Biomasse; Physiologie; Marée noire; Amoco Cadiz; Zooplankton; Biomass; Physiology; Spill.
Ano: 1978
URL: http://archimer.ifremer.fr/doc/00306/41728/40939.pdf

Effect of shear velocity and flow regimes on scallop post-larval detachment feed on two different diets
Provedor de dados: 5
Autores: Gagne, Renee; Tremblay, Rejean; Olivier, Frederic; Pernet, Fabrice; Miner, Philippe; Samain, Jean-francois.
Through biological flume experiments, we studied the effect of shear velocity and attachment period on the percent detachment of Pecten maximus post-larvae of different sizes reared on two experimental diets. The first diet, (Pavlova lutheri, Isochrysis galbana, Chaetoceros calcitrans), which served as a reference diet (PTC), is commonly used in bivalve hatcheries; the second is the PTC diet with the addition of Rhodomonas salina (PTCR). Our results indicate that the detachment of post-larvae fed PTCR diet showed significant interactions between scallop length, attachment period and shear stress, while the post-larvae feed with the PTC diet showed only effect of shear stress factor. Furthermore, post-larvae exposed to various flume velocities showed...
Tipo: Text
Palavras-chave: Attachment; Pecten maximus; Benthic boundary layer; Flume; Diet.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00111/22219/20056.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

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

Approche de l'état physiologique de l'huître creuse Crassostrea gigas au cours d'un cycle saisonnier à Marennes-Oléron
Provedor de dados: 5
Autores: Moal, Jeanne; Samain, Jean-francois; Bodoy, Alain; Le Coz, Jean-rene.
The energy charge was measured for two Crassostrea gigas populations, during an annual survey at Marennes Oleron, to appreciate the condition of health of these oysters. It is assumed that the actual decrease in production of this area is related to a biomass overload which affects the oysters by lowering their scope for growth. Energy charge, an index developped by ATKINSON (1968), defines the energy equilibrium of organisms. It is the adenylic nucleotide ratio: E.C = (ATP + 1/2ADP)/ATP + ADP + AMP). We have measured this parameter to determine the state of health of these oysters. A methodological study has been conducted previously to define the conditions of sampling, conservation and extraction for a HPLC assay. The HPLC method (high performance...
Tipo: Text
Palavras-chave: Marennes Oleron; Seasonal variations; Crassostrea gigas; Physiological indice; Nucleotides; Energy charge; Marennes Oléron; Cycle saisonnier; Crassostrea gigas; Indiced physiologique; Nucléotides; Charge énergétique.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/1987/publication-2869.pdf

An amylase gene polymorphism is associated with growth differences in the Pacific cupped oyster Crassostrea gigas
Provedor de dados: 5
Autores: Prudence, Marie; Moal, Jeanne; Boudry, Pierre; Daniel, Jean-yves; Quere, Claudie; Jeffroy, Fanny; Mingant, Christian; Ropert, Michel; Bedier, Edouard; Van Wormhoudt, A; Samain, Jean-francois; Huvet, Arnaud.
This study investigated the non-neutrality of genetic polymorphism in two alpha-amylase genes (AMYA and AMYB) in the oyster Crassostrea gigas. Bi-parental oyster families, bred to be polymorphic for markers in these genes, were monitored for growth and survival for 1 year under standard culture conditions in two French production sites. Within-family genotype frequencies indicated that the two amylase genes were closely linked (c. 1.7 cM). Within two of three families, significant differences in growth were observed between genotypes at one of the two production sites, suggesting that this polymorphism is not neutral and might be under selection because of its role in digestive function. Estimated daily yields were different between amylase genotypes,...
Tipo: Text
Palavras-chave: Growth; Genotype; Digestive enzyme; Bivalve; Alpha amylase.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1691.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

Interspecific and intraspecific variability of the chemical-composition of marine-phytoplankton
Provedor de dados: 5
Autores: Moal, Jeanne; Martin-jezequel, Veronique; Harris, Rp; Samain, Jean-francois; Poulet, Sa.
Tipo: Text
Ano: 1987
URL: http://archimer.ifremer.fr/doc/00108/21908/19499.pdf

Tissue expression of two alpha-amylase genes in the Pacific oyster Crassostrea gigas. Effects of two different food rations
Provedor de dados: 5
Autores: Huvet, Arnaud; Daniel, Jean-yves; Quere, Claudie; Dubois, Solene; Prudence, Marie; Van Wormhoudt, A; Sellos, D; Samain, Jean-francois; Moal, Jeanne.
A semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay was developed to estimate tissue-specific expression of two amylase genes in five different tissues of the Pacific oyster Crassostrea gigas and the experimental effects of food level on the cellular, enzymatic and gene expression changes of the digestive gland. Results indicated that both genes were transcribed at different levels depending on tissue type. A strong preferential expression of both amylase genes was observed in the digestive gland leading to high amylase activities, in accordance with the digestive function of this organ. Traces of gene expression and activity were observed in other analysed tissues. These appeared higher in labial palps than in other...
Tipo: Text
Palavras-chave: Oyster; Gene expression; Food regulation; Digestive enzyme activity; Alpha amylase.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/publication-394.pdf

Relation between lipid and fatty acid composition of eggs and larval survival in white pacific shrimp (Penaeus vannamei, Boone, 1931)
Provedor de dados: 5
Autores: Palacios, Elena; Rehault, Jean Pierre; Heras, Horacio; Marty, Yannick; Moal, Jeanne; Samain, Jean-francois.
In this study, lipid classes and fatty acid composition were determined in eggs of P. vannamei as a function of survival to zoea III stage. Spawns were reared individually to zoea III and grouped, according to their final survival to this larval stage, into spawns of high and low survival. Eggs of individual spawns were analyzed for lipid and fatty acid composition of neutral and polar lipids and the results were then grouped according to survival to zoea III. The lipids within each group (high and low survival to zoea III) were pooled for the separation of phospholipids and the analysis of their fatty acid composition. Higher levels of triglycerides, carotenoids, and linoleic (18: 2n-6) acid in eggs were associated with improved survival to zoea III....
Tipo: Text
Palavras-chave: Triglycerides; Phospholipid; Larval quality; Larval culture; Carotenoid.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/2002/publication-786.pdf

Effect of a mono-specific algal diet on immune functions in two bivalve species - Crassostrea gigas and Ruditapes philippinarum
Provedor de dados: 5
Autores: Delaporte, Maryse; Soudant, Philippe; Moal, Jeanne; Lambert, Christophe; Quere, Claudie; Miner, Philippe; Choquet, Gwenaelle; Paillard, Christine; Samain, Jean-francois.
The impact of diets upon the fatty acid composition of haemocyte polar lipids and consequently upon immune parameters has been tested in the oyster Crassostrea gigas and the clam Ruditapes philippinarum. Oysters and clams were fed each of three cultured algae: Chaetoceros calcitrans, which is rich in 20:5(n-3) and 20:4(n-6) and poor in 22:6(n-3) fatty acids; T-Iso (Isochrysis sp.), which is rich in 22:6(n-3) and deficient in 20:5(n-3) and 20:4(n-6); and Tetraselmis suecica, which is deficient in 22:6(n-3) and contains only small amounts of 20:5(n-3) and 20:4(n-6). Fatty acid composition of haemocyte polar lipids was greatly affected by the diet. Oysters and clams fed C. calcitrans maintained a higher proportion of 20:5(n-3) and 20:4(n-6) in their haemocyte...
Tipo: Text
Palavras-chave: Ruditapes philippinarum; Crassostrea gigas; Polyunsaturated fatty acids; Phagocytosis; Oxidative activity; Haemocyte membrane; Nutrition; Immunology; Bivalve; Immunologie; Bivalve; Ruditapes philippinarum; Crassostrea gigas; Acides gras poly insatures; Phagocytose; Flambee respiratoire; Membrane; Hemocyte; Nutrition.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/publication-354.pdf

Delivery of riboflavin to larval and adult pacific oysters, Crassostrea gigas Thunberg by lipid spray beads
Provedor de dados: 5
Autores: Langdon, Cj; Seguineau, Catherine; Ponce, B; Moal, Jeanne; Samain, Jean-francois.
Lipid spray beads (SB) were prepared containing 13% w/w particulate riboflavin. Beads suspended in seawater lost 73% riboflavin after 24 h. Release of riboflavin from SE ingested by Pacific oyster (Crassostrea gigas) larvae was observed under epifluorescent light. Riboflavin concentrations in tissues of adult oysters fed on riboflavin-SB were significantly (SNK, P &lt; 0.05) greater than those of oysters fed on seawater-filled SE. Concentrations of riboflavin in oysters exposed to dissolved riboflavin were not significantly greater than those of oysters fed on seawater-filled SE: indicating that elevated riboflavin concentrations in oysters fed on riboflavin-SB were attributable to breakdown of ingested beads rather than uptake of dissolved riboflavin...
Tipo: Text
Palavras-chave: Spray beads; Lipid; Riboflavin; Oyster; Larvae; Crassostrea gigas.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00000/10493/9511.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

Lipid composition of the pacific lion-paw scallop, Nodipecten subnodosus, in relation to gametogenesis - 2. Lipid classes and sterols
Provedor de dados: 5
Autores: Palacios, Elena; Racotta, I.s.; Arjona, O; Marty, Y; Le Coz, Jean-rene; Moal, Jeanne; Samain, Jean-francois.
Knowledge on the energy distribution during the reproductive cycle of the giant lion-paw scallop, Nodipecten subnodosus is limited, but necessary for aquaculture purposes. In a previous work, we found that natural food availability can sustain the full cost of gametogenesis in optimal environmental conditions. The present study analyses the lipid and sterol classes' composition of several tissues during gametogenesis. In female gonads, the quantity of triacylglycerol (TG) increased parallel to gametogenesis from December (spawned gonads, 0.7 mg g(-1) or 7% of total lipids) to June (ripe gonads, 52 mg g(-1) or 66% of total lipids). In male gonads sampled in June, the concentration of TG (0.7 mg g(-1) or 3.5% of total lipids) and esterified sterols was...
Tipo: Text
Palavras-chave: Sterol; Reproduction; Phospholipid; Mollusks; Acylglycerides.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2635.pdf

Impact of 20 : 4n-6 supplementation on the fatty acid composition and hemocyte parameters of the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Delaporte, Maryse; Soudant, Philippe; Moal, Jeanne; Giudicelli, Emilie; Lambert, Christophe; Seguineau, Catherine; Samain, Jean-francois.
Arachidonic acid (20:4n-6, ArA) and its eicosanoid metabolites have been demonstrated to be implicated in immune functions of vertebrates, fish, and insects. Thus, the aim of this study was to assess the impact of ArA supplementation on the FA composition and hemocyte parameters of oysters Crassostrea gigas. Oyster dietary conditioning consisted of direct addition of ArA solutions at a dose of 0, 0.25, or 0.41 mu g ArA per mL of seawater into tanks in the presence or absence of T-Iso algae. Results showed significant incorporation of ArA into gill polar lipids when administered with algae (up to 19.7%) or without algae (up to 12.1%). ArA supplementation led to an increase in hemocyte numbers, phagocytosis, and production of reactive oxygen species by...
Tipo: Text
Palavras-chave: Hemocyte parameters; Oyster immunity; Arachidonic Acid; Poly unsaturated fatty acids; Nutrition; Bivalve; Crassostrea gigas.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1876.pdf