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Registros recuperados: 65 | |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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Degremont, Lionel; Bedier, Edouard; Soletchnik, Patrick; Ropert, Michel; Samain, Jean-francois; Boudry, Pierre. |
The French project "Morest", coordinated by IFREMER, aims to a better understanding of the causes of summer mortalities in juvenile oysters by a multidisciplinary approach. Within this program, a first generation (G1) was bred in 2001 to assess to what extent genetic variability exists for this trait in French populations. 17 half-sib families (HSF) including 44 full-sib families (FSF) were obtained in the G1, and each FSF was reared in three sites along the French coast during the summer period. Significant differences in survival were observed among HSF, clearly indicating a genetic basis for survival. Estimation of heritability for survival was very high: 0.81  0.29. In 2002, 3 "good" HSF and 3 "bad" HSF were selected on their survival... |
Tipo: Text |
Palavras-chave: Selection; Genetic; Mortalities; Crassostrea gigas; Oyster. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/acte-3439.pdf |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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Registros recuperados: 65 | |
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