|
|
|
Registros recuperados: 28 | |
|
|
Suquet, Marc; Agogue, Julie; Brizard, Raphael; Haffray, Pierrick; Labbe, Catherine; Le Coz, Jean-rene; Pepin, Jean-francois; Rault, Paul; Saulnier, Denis. |
Ce rapport fait état d'une étude réalisée au laboratoire de Génétique et Pathologie de l'IFREMER dans le cadre de l'analyse d'épisodes de mortalité anormale survenue en écloserie privée de crevettes pénéides. Plusieurs hypothèses ont été avancées. La présence de Vibrio harveyi a amené à constituer une collection de 40 souches à partir desquelles une identification bactériologique a été effectuée. Elle montre en effet une dominance de souches appartenant à un groupe homogène de Vibrio harveyi. La technique de ribotypage (digestion d'ADN génomique, transfert de Southem-blot et hybridation avec une sonde spécifique) est alors mise en place. Plusieurs difficultés techniques ont ralenti l'analyse et n'ont donc pas permis d'avoir des résultats assez avancés pour... |
Tipo: Text |
Palavras-chave: Huître creuse; Crassostrea gigas; Tétraploïdes; Sperme; Conservation; Diagnostic zoo-sanitaire; Flore bactérienne; Herpès virus.. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/00304/41554/40762.pdf |
| |
|
| |
|
| |
|
|
Robert, Rene; Chretiennot-dinet, Marie-josèphe; Kaas, Raymond; Martin-jezequel, Véronique; Moal, Jeanne; Le Coz, Jean-rene; Nicolas, Jean-louis; Bernard, Eudes; Connan, Jean-paul; Le Dean, Loic; Le Gourrierec, Gaetane; Leroy, Bertrand; Quere, Claudie. |
in mollusc hatcheries. Consequently, we assessed themost commonly used species to establish their growth and size profiles, their cytomorphological, biochemical, biomolecular identification as well as their cytometer signs, and also their ability to grow under extreme conditions of temperature and salinity. This work aimed at matching the conformity of the strains used in Argenton (dispatched to most of the French commercial hatcheries) to those of a referenced culture collection. A previous screening preceded this study, because of the 45 species and/or clones held originally, Argenton kept no more than 15 species. As most of the latter are also represented in referenced collection, our strains are therefore correctly identified. On the other hand, the... |
Tipo: Text |
Palavras-chave: Ecological limits; Biomolecular profile; Flow cytometry; Biochemical composition; Cytomorphology; Phytoplankton; Mollusc; Hatchery; Ecotolérance; Profil biomoléculaire; Cytométrie en flux; Composition biochimique; Cytomorphologie; Phytoplancton; Mollusques; Ecloserie. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/rapport-1546.pdf |
| |
|
|
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 |
| |
|
|
Vahirua Lechat, I; Laure, F; Le Coz, Jean-rene; Bianchini, J; Bellais, M; Le Moullac, Gilles. |
The fatty acid and sterol composition of the oyster Pinctada margaritifera during oogenesis and in eggs was analysed. No major differences were observed during oogenesis, but the egg composition was significantly different from that of gonads. The amount of saturated fatty acids was the highest in eggs and the C16:0 predominant (P < 5%); by contrast, the amount of 22:6(n-3) was significantly lower (P < 5%) than in gonads. No major differences were observed for the polar lipid (PL) composition during oogenesis. The main free sterols in gonads and eggs were cholesterol and brassicasterol. Among free sterols, the proportion of cholesterol diminished continuously from the beginning to the end of gonad maturation, and this decrease persisted in eggs after... |
Tipo: Text |
|
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-5902.pdf |
| |
|
|
Mugnier, Chantal; Justou, Carole; Lemonnier, Hugues; Patrois, Jacques; Ansquer, Dominique; Goarant, Cyrille; Le Coz, Jean-rene. |
Shrimp aquaculture in New Caledonia is subject to seasonal mortalities during grow-out due to highly virulent Vibrio nigripulchritudo (Vn). To understand the mechanisms affecting shrimp resistance and leading to significant mortality, a shrimp ecophysiology and immunology survey was conducted on two farms, the first considered as a "control" farm (HC), the second affected by the disease (DF). Mortality observed during the survey at DF started 50 days after stocking and was typical of this disease. The main observations regarding shrimp were: (a) growth was not affected by the disease and was faster in the DF than in the HC pond; (b) disease did not affect one sex more than the other, or a specific part of the population in terms of weight; (c) the physical... |
Tipo: Text |
Palavras-chave: Vibriosis; Penaeid shrimp; Field survey; Physiology; Immunology; Nutritional status. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00176/28764/27567.pdf |
| |
|
|
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 |
| |
|
|
Suquet, Marc; Labbe, C.; Brizard, Raphael; Donval, Anne; Le Coz, Jean-rene; Quere, Claudie; Haffray, P.. |
Changes in sperm features during the movement phase are especially interesting to study in external fertilization species whose sperm duration movement is long because this implies a significant adaptation of moving cells to the external medium. This study describes the changes in tetraploid Pacific oyster sperm characteristics in relation to time post activation. Sperm individually collected on three tetraploid males were activated in seawater. Their features were analysed over a 24 h period and compared to a sperm pool collected on three diploid males as a reference. The percentage of motile spermatozoa, the intracellular ATP content, and the fine structure of spermatozoa were studied in relation to time post activation. Furthermore, the fertilisation... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Sperm; Tetraploid; Motility; ATP; Ultrastructure. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00006/11756/8639.pdf |
| |
|
|
Le Moullac, Gilles; Cheize, Marie; Gastineau, Olivier; Daniel, Jean-yves; Le Coz, Jean-rene; Huvet, Arnaud; Moal, Jeanne; Pouvreau, Stephane; Van Wormhoudt, A; Samain, Jean-francois. |
The purpose of this study is to examine the response of the oyster Crassostrea gigas to sulphide at different biological scales. A first experiment was designed to measure for 20 h the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of sulphide (0, 3, 6, 12, 20, and 40 mu M). The second experiment was carried out to evaluate the metabolic adaptations to chronic sulphide exposure for 10 days by measuring PK and PEPCK enzyme activities, succinate and alanine content, the adenylate energy charge (AEC), and the activity of the electron transport system (ETS)in whole oysters at above 20 mu M. PK and PEPCK mRNAs and enzyme activities have been measured in adductor muscle. When exposed to sulphide above 20 mu M, CR... |
Tipo: Text |
Palavras-chave: ATP; AEC; Electron transport system; Succcinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Oxygen consumption; Clearance rate; Crassostrea gigas; Sulphide; Oyster. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3924.pdf |
| |
|
|
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 |
| |
|
|
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 |
| |
|
| |
|
| |
|
|
Groison, A. -l.; Fauvel, Christian; Suquet, Marc; Kjesbu, O. S.; Le Coz, Jean-rene; Mayer, I.; Cosson, J.. |
P>The objective of this paper is to characterize some of the sperm motility parameters in European hake (Merluccius merluccius), which is considered to be a species with aquaculture potential. The total ATP, ADP and AMP concentrations were determined using high-performance liquid chromatography on hake sperm samples collected during the winter-early spring in the Bay of Biscay (France) (n = 22) and on hake sperm samples collected during the summer-early autumn in waters off Western Norway (n = 5). The Adenylate Energy Charge (AEC) was deduced from these data. Computer Assisted Sperm Analysis (CASA) was used to measure a series of parameters characterizing the motility and the sperm swimming performances. Changes in salinity of the swimming medium... |
Tipo: Text |
|
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00015/12644/9883.pdf |
| |
|
|
Bougaran, Gael; Rouxel, Catherine; Dubois, Nolwenn; Kaas, Raymond; Grouas, Sophie; Lukomska, Ewa; Le Coz, Jean-rene; Cadoret, Jean-paul. |
Microalgae offer a high potential for energetic lipid storage as well as high growth rates. They are therefore considered promising candidates for biofuel production, with the selection of high lipid-producing strains a major objective in projects on the development of this technology. We developed a mutation-selection method aimed at increasing microalgae neutral lipid productivity. A two step method, based on UVc irradiation followed by flow cytometry selection, was applied to a set of strains that had an initial high lipid content and improvement was assessed by means of Nile-red fluorescence measurements. The method was first tested on Isochrysis affinis galbana (T-Iso). (...) |
Tipo: Text |
Palavras-chave: Strain selection; Isochrysis; Neutral lipid; Ultra violet; Flux cytometry; Biofuel. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00085/19643/17418.pdf |
| |
|
|
Chu, F; Lund, E; Littreal, P; Ruck, K; Harvey, E; Le Coz, Jean-rene; Marty, Y; Moal, Jeanne; Soudant, P. |
The kinetics and efficiency of sterol production and bioconversion of phytosterols in two heterotrophic protists Oxyrrhis marina and Gyrodinium dominans were examined by feeding them two different algal species (Rhodomonas salina and Dunaliella tertiolecta) differing in sterol profiles. R. salina contains predominantly brassicasterol (99%) and < 2% cholesterol. The major sterols in D. tertiolecta are ergosterol (45-49%), 7-dehydroporiferasterol (29-31%) and fungisterol (21-26%). O. marina fed R. salina metabolized dietary brassicasterol to produce 22-dehydrocholesterol and cholesterol. O. marina fed D. tertiolecta metabolized dietary sterols to produce cholesterol, 22-dehydrocholesterol, brassicasterol and stigmasterol. G. dominans fed either R. salina... |
Tipo: Text |
|
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-5167.pdf |
| |
|
|
Le Moullac, Gilles; Vairuha-lechat, Isabelle; Bianchini, Jean Pierre; Le Coz, Jean-rene; Tiapari, Jerome; Laure, Frédéric; Mitermite, Yves. |
Cette étude financée par le Ministère de l’Outre-Mer est une collaboration de l’Ifremer avec l’Université de Polynésie Française et l’Institut Louis Malardé. Cette étude a permis l’acquisition de connaissances nouvelles sur la nutrition de l’huître perlière Pinctada margaritifera dans le milieu naturel, et ainsi, de mieux envisager les besoins nutritionnels pendant la reproduction. Les besoins en lipides, acides gras et stérols, ont été spécifiquement étudiés. La composition en acides gras neutres et polaires des gonades femelles ne subit pas de variations significatives au cours de l’ovogenèse. En revanche, la composition des oeufs après la ponte subit des modifications significatives au sein des lipides neutres et polaires. Cependant ces modifications... |
Tipo: Text |
|
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/00182/29287/27774.pdf |
| |
|
|
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 |
| |
|
| |
Registros recuperados: 28 | |
|
|
|