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| Registros recuperados: 148 | |
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| Alzieu, Claude; Heral, Maurice. |
| The toxic effect of trialkyltin compounds is used in antifouling paints to protect vessels against biofouling organisrns. Tributyltin oxide (TBTO) or fluoride (TBTS) leaches by diffusion from the paint layer into the seawater. Trialkyltin compounds in aqueous solutions are resistant to hydrolysis and biodegradation, but are rapidly converted into diakyl, monoalkyl and inorganic tin by UV irradiation. As inhibiting agents of the oxidative phosphorylation, organotin compounds are extremely dangerous for aquatic organisms such as molluscs. The following estimated toxicity levels for Crassostrea gigas oyster larvae have been put forward : at 100 µg.l(1) the fecondation is inhibited, at 10 µg.l1 the already of 20 % of the eggs is affected larval development... |
| Tipo: Text |
Palavras-chave: Toxicity; Fluoride; Tribultyltin oxide; Toxic effect; Oysters; Crassostrea gigas. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/publication-2931.pdf |
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| Alzieu, Claude; Heral, Maurice; Dreno, Jean-paul. |
| On 17 January 1982, the Minister of the Environment issued a decree limiting the use of anti-fouling paints that have organostannic derivatives for boats of less than 25 metres in length. This decision, taken after advice from the Commission for Assessing the Ecotoxicity of Chemical Substances, was meant to protect oyster-farming against the serious pollution linked to the growing use of this type of paint. These provisions, adopted only a few months after the harmful effects of organo-tins were brought to light, made it possible to protect oyster farming in some endangered areas. Moreover, they brought on an international awareness of the ecological risks linked to the struggle against marine biological fouling. |
| Tipo: Text |
Palavras-chave: Ostréiculture; Impact; Peintures antisalissures. |
| Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/1989/publication-3025.pdf |
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| Alzieu, Claude; Heral, Maurice; Thibaud, Yves; Dardignac, Marie-jose; Feuillet, Michèle. |
| Experiments in oyster-breeding areas where oyster Crassostrea gigas suffers from anomalies of calcification, show an obvious correlation between the importance of the malformation of shells and the vicinity of port areas where a great number of boats usually stay. Organotin compounds contained in antifouling paints, and more precisely Tributyltin fluoride (TBTF) induce, in experimental environment, similar anomalies to those observed in natural environment. The amounts of total tin in the tissues of oysters living in the vicinity of spots where organotin products are brought in, can reach high values, though they appear to decrease rapidly whereas the environmental contamination lessens. The authors suggest that results of organotin upon the mechanisms of... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Pollution effects; Toxicity; Calcification; Fouling control; Paints. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-1898.pdf |
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| Bacher, Cedric; Baud, Jean-pierre; Bodoy, Alain; Deslous-paoli, Jean-marc; Dreno, Jean-paul; Heral, Maurice; Maurer, Daniele; Prou, Jean. |
| An assessment of the reared stocks of the Pacific oyster (Crassostrea gigas ) has been recently conducted on the major French areas of molluscs culture. The methodology proposed included both estimates of densities obtained by subsampling in the field, and aerial photographs which covered the cultivated, intertidal area. The size and the number of samples were designed to reach a precision of 10% on the final assessment in each area. The field work consisted in weighing and counting the oyster in unit areas of 0.5 m2 for the bottom culture or in trays or bags, for the off bottom technique. These results give a better knowledge of the technique evolution and of the general structures in the cultivated areas. |
| Tipo: Text |
Palavras-chave: Modeling; Estimation; Stocks; Crassostrea gigas; Oysters. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/1986/acte-2864.pdf |
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| Bacher, Cedric; Deslous-paoli, Jean-marc; Heral, Maurice; Prou, Jean. |
| The expansion of shellfish culture businesses (oysters, mussels, clams...) gives way to a competition for the use of limited food resources, especially in the Marennes-Oléron basin where water circulation is slow. Increasing the amount of cultivated molluscs leads, from a biological point of view, to:- a drop in growth performances- a rise in chronic mortalities, higher and higher, due to a weakness in the physiological state with a lack of stocks which would have compensated the habitat seasonal shortages (end of winter, etc...)- a greater weakness to diseases, linked to a deficient physiological state and a density rise which increases the proximity rate and thus, parasite propagation speed.For these primary reasons, and for the future of oyster culture,... |
| Tipo: Text |
Palavras-chave: Modélisation; Estimation; Echantillonnage; Mollusques; Marennes Oléron; Evaluation stocks. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/1986/rapport-3841.PDF |
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| Bacher, Cedric; Heral, Maurice; Deslous-paoli, Jean-marc; Razet, Daniel. |
| The growth of oysters (Crassostrea gigas) is modeled in order to study the trophic capacity of the Bay of Marennes Oléron. Total seston and amount of protids, lipids, and carbohydrates converted to energy are the environmental factors taken into account. Time series of these variables are derived during 2 yr with a daily time step from a linear regression including the tidal velocity, the height of the water column, and the wind velocity. A model of the energetic budget based on assimilation and respiration terms and depending on the previous time series is run to simulate the individual growth of an oyster. The knowledge of the number of oysters, the flow of water entering the bay, and the volume of the bay allows us then to estimate that 7% of the... |
| Tipo: Text |
Palavras-chave: Marennes Oléron; Crassostrea gigas; Huîtres; Croissance; Modélisation; Marennes Oleron bay; Crassostrea gigas; Oysters; Growth; Modelisation. |
| Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/publication-3051.pdf |
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| Barille, Laurent; Heral, Maurice; Barilleboyer, Al. |
| An ecophysiological deterministic model of growth, reproduction and interactions between the bivalve and its estuarine environ ment was established for the Japanese oyster Crassostrea gigas. The environmental variables used in the model are: total particulate matter, particulate organic matter, particulate inorganic matter, chlorophyll, phaeopigments, proteins, lipids and carbohydrates. Rates of clearance, filtration, ingestion, absorption and respiration along with efficiencies of retention, selection and absorption are modelled with endogenous (dry weight of the animal, energy allocation between growth and reproduction) and exogenous variables (temperature, food quality and quantity). The model simulate the temporal evolution of two compartments: somatic... |
| Tipo: Text |
Palavras-chave: Crassoslrea gigas; Croissance; Écophysiologie; Modélisation; Turbidité; Crassostrea gigas; Ecophysiology; Growth; Modelling; Turbidity. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00038/14892/12219.pdf |
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| Bayne, Bl; Iglesias, Jip; Hawkins, Ajs; Navarro, E; Heral, Maurice; Deslous Paoli, Jean-marc. |
| Mussels were fed four concentrations of seston (between 099 and 103mgtotalseston P), comprising three levels of organic content (719, 636 and 408%), made up from natural silt and two species of cultured phytoplankton. Two of the seston concentrations were below, and two above, the threshold at which pseudofaeces were produced. Measurements of physiological traits (filtration rates, pseudofaeces production, selection efficiency, absorption efficiency, absorption rates and rates of oxygen consumption) were made after 2 days and, for two of the seston concentrations, also after 12 days. When fed at a high concentration of seston of low organic content, the mussels increased their filtration rate, rejected a higher proportion of filtered material as... |
| Tipo: Text |
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| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/1993/publication-3069.pdf |
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| Boudry, Pierre; Naciri, Yamama; Heral, Maurice; Collet, Bertrand; Bougrier, Serge; Geffard, Olivier; Ledu, Christophe; Phelipot, Pascal; Heurtebise, Serge; Gerard, Andre. |
| Le programme de recherche présenté ci-dessous est le fruit d'une réflexion conjointe entre généticiens et physiologistes afin de mettre sur pied un ensemble d'expériences permettant d'étudier les bases génétiques de la variabilité des caractères impliqués dans la croissance chez l'huître creuse, Crassostrea gigas. |
| Tipo: Text |
Palavras-chave: Génétique; Sélection génétique; Génétique des populations; Croissance; Crassostrea gigas. |
| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00044/15518/12905.pdf |
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| Chevalier, Claude; Heral, Maurice; Razet, Daniel. |
| Dans le contexte de développement agricole très actif des trente dernières années les marais atlantiques littoraux qui couvrent, pour leur partie endiguée environ 300.000 ha. ont été et continuent d'être soumis à des transformations importantes qui influent sur la circulation et la qualité des eaux de surface. Ce développement, visant à une amélioration de la productivité et à une meilleure intégration de l' activité agricole dans les grands processus économiques, s'est appuyé, là comme ailleurs, sur les intensifications fourragère et surtout céréalière. L'adaptation de ce modèle général aux caractéristiques écologiques du milieu nécessitait de limiter les effets des excès d'eau hivernaux sur la mise en culture ainsi que ceux de la sécheresse estivale sur... |
| Tipo: Text |
Palavras-chave: Marais atlantique; Littoral; Agriculture; Conchyliculture; Impact; Compatibilité; Charente Maritime Dep.. |
| Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00071/18235/15795.pdf |
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| Coeurdacier, J.-m.; Heral, Maurice; Liange, M.; Moreau, Jean; Prou, Jean; Razet, Daniel; Williot, P.. |
| Reject waters from sea fish-ponds of rearing trout and turbot show increased ammonia and phosphate values. Protid, lipid and glucid contents of the waters remain low, with total values which do not overpass 1.7 mg.l super(1). After showing that the oysters were likely to absorb sewage from fish farming ponds, the authors examine whether, for epidemiologic and rearing methods reason, it is possible for both types of farming to cohabit as for as zoopathology is concerned. The possible accumulation of antibiotic in mollusks and antibioresistance transfer to germs may be pathogenic for man, are also discussed. |
| Tipo: Text |
Palavras-chave: Aeromonas hydrophila Escherichia coli Crassostrea gigas Bivalvia Antibiotics Growth Environmental effects Bacteria Shellfish culture; Pollution effects Fish culture. |
| Ano: 1982 |
URL: http://archimer.ifremer.fr/doc/1982/publication-1855.pdf |
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| Collet, Bertrand; Boudry, Pierre; Bougrier, Serge; Heurtebise, Serge; Phelipot, Pascal; Ledu, Christophe; Morand, Berenice; Heral, Maurice; Gerard, Andre. |
| A European programme (GENEPHYS) was launched in 1996 to study the genetic basis and variability of physiological characters involved in growth in Crassostrea gigas. This research programme was a prerequisite for any genetic selection programme on physiological functions. Research groups from Ireland, England, Greece and France are involved in this project and participate in genetic analyses (allozymes and microsatellites) and physiological analyses (ecophysiology, enzymology, stress proteins). Ifremer at La Tremblade was responsible for producing the biological material while Ifremer-CREMA (human-influenced marine ecosystems research centre) was responsible for carrying out non-destructive physiological analyses. |
| Tipo: Text |
Palavras-chave: Sélection génétique; Croissance; Crassostrea gias; Génétique. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/1997/acte-3243.pdf |
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| Registros recuperados: 148 | |
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