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Registros recuperados: 81 | |
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Maurer, Daniele. |
The survey was carried out during the first two weeks of August on 52 oyster farmers, representing 8% of professional oyster farmers. Each oyster farm was represented with respect to its importance. The survey unit was the "pond" defined according to qualitative and quantitative criteria. Approximately 270 ponds were identified in 220 farms. This number was sufficiently high to explain observed patterns. The results reported here could not be very precise due to the way the data were collected. For example, the dates of first occurrence of mortality events may correspond to dates when mortality was first observed rather than when it actually started. |
Tipo: Text |
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Ano: 1982 |
URL: http://archimer.ifremer.fr/doc/1982/rapport-4319.pdf |
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His, Edouard; Maurer, Daniele; Robert, Rene. |
L’acétate de tributyle-étain, composé actif de certaines peintures antisalissures, représente un danger certain pour les zones conchylicoles de captage (E. HIS et R. ROBERT, 1980 et R. ROBERT et E. HIS, 1981). Les méthodes chimiques actuelles ne sont pas assez sensibles pour permettre le dosage de ce produit dans l'eau de mer, au seuil de toxicité pour les larves d'huitres. Une échelle d'action pour douze concentrations comprises entre 100 ug/l. et 0,02 ug/ l., sur les véligères de Crassostrea gigas est proposée. Elle permet d’évaluer le degré de contamination de l'eau de mer d'un part de plaisance et son évolution. |
Tipo: Text |
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Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/00090/20162/17815.pdf |
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His, Edouard; Maurer, Daniele; Robert, Rene. |
The spat production in the Bay of Arcachon has been recently disturbed. Bioassays using algae used as food for oyster larvae have shown that the organotin paints affect or inhibit growth of Isochrysis galbana and Chaetoceros calcitrans . Fresh waters coming into the bay and shore sediment did not affect the growth of these algae. Bioassays proposed by Woelke (1967) using embryos and larvae of Crassostrea gigas have shown that the quality of the sea water from Arcachon harbour has been improved a few months after the use of organotin paints has been prohibited. Likewise fresh waters are free from any micropollutants that could drastically disturb the reproduction of C. gigas in the bay. |
Tipo: Text |
Palavras-chave: Marine mollusks; Pollution effects; Recruitment; Population number; Oyster culture. |
Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/publication-1788.pdf |
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Maurer, Daniele; Borel, Michel. |
Two-year-old oysters have a physiology which is reproduction-oriented, their maturation occurring synchronously among oysters from the same batch. The importance of the spring accumulation of glycogenated stocks varies through the years and correlates with the growth stage. Glucidic components are quickly used during the month preceding egg-laying and are transformed into lipid stocks for the oocytes. One-year-old oysters develop at different rates, some of them not showing any sign of maturation and the percentage of laying individuals varies through the years. Glycogenated stocks accumulate in a similar way in both age-classes and their more precocious and more intense use by young molluscs is not necessarily linked with their gametogenesis and growth,... |
Tipo: Text |
Palavras-chave: Bay of Arcachon; Maturation; Biochemistry; Crassostrea gigas; Bassin d'Arcachon; Maturation; Biochimie; Crassostrea gigas. |
Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/acte-6182.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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Maurer, Daniele; Comps, Michel; His, Edouard. |
Summer mortalities in the Pacific oyster in the Bay of Arcachon were analysed during four years (1981 to 1984). Mortalities occur mostly among one year old oyster and affect the whole bay, with different prevalence. The phenomenon occurs at certain times during the summer spawning period and is associated with high temperatures. A thinning of the digestive tubule epithelium is observed, but there is no evidence of infectious disease. The failure to find a causative agent, pollution or pathogen, tends to strengthen a physiological disorder hypothesis, related to environmental conditions. The influence of external (temperature, available food) and internai factors (length, maturation, spawning) on this phenomenon is discussed. A comparaison is drawn with... |
Tipo: Text |
Palavras-chave: Bay of Arcachon; Summer mortalities; Crassostrea gigas; Bassin d'Arcachon; Mortalités estivales; Crassostrea gigas. |
Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/1986/publication-4318.pdf |
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Maurer, Daniele; Borel, Michel; Dreno, Jean-paul. |
L'élaboration d'un modèle de gestion d'un bassin conchylicole nécessite, en particulier, la connaissance de l’évolution des stocks d'huîtres d'une année à l'autre afin d'en apprécier l'influence éventuelle sur le rendement. Le présent travail décrit la méthodologie utilisée et les résultats obtenus au cours de la première estimation du stock d'huîtres Crassostrea gigas en élevage dans le bassin d'Arcachon en 1985. Cette estimation nécessite l'utilisation simultanée de photographies aériennes (évaluation de la surface réellement exploitée ) et de sondages-terrain (évaluation de la biomasse par unité de surface). Ces derniers ont également permis de valider les résultats obtenus par photographie. En 1985, le taux d'exploitation variait, selon la zone... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Biomasse; Bassin d'Arcachon; Crassostrea gigas; Biomass; Bay of Arcachon. |
Ano: 1987 |
URL: http://archimer.ifremer.fr/doc/00102/21342/18965.pdf |
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Maurer, Daniele; Parache, Alain; Dreno, Jean-paul. |
Afin d ' améliorer la précision des résultats et depuis 1986, quelques modifications ont été apportées à la stratégie d'échantillonnage qui avait été adoptée en 1985 : - prise en compte de la structure en âge de l a population, en différenciant les huîtres âgées de 1 an de celles d'âge supérieur, - traitement séparé des poches et des collecteurs pour l'élevage en sur élevé . Au cours des trois années , le stock d'huîtres en élevage est resté relativement stable : 1985 37 996 t ± 1 970 t précision 5,1% 1986 37 835 t ± 4 196 t précision 11,1% 1987 39 079 t i 3 350 t précision 8,6% avec environ 80% représenté par la culture à plat. Cependant, il est apparu que les différentes variables estimées et leur précision variaient d'une année à l 'autre en liaison... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Biomasse; Bassin d'Arcachon. |
Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00430/54141/55471.pdf |
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Heral, Maurice; Drinkwaard, A.; Bohle, B.; Figueras, Antonio; Lavoie, R.; Maurer, Daniele. |
The world aquaculture production (fresh and marine waters) achieved 11.1 million tonnes in 1986 (FAO, 1989). The molluscs represented 21 % of the total production. Marine aquaculture with 5.45 million tonnes reached 49% of the total production. The marine cultivated mollusc production was 2.25 million tonnes due mainly to oysters (36%), mussels (34%), clams (16%), and scallops (6%). As the aquaculture production is clearly identified in the statistics only since 1984, the evolution of the production of oysters and mussels for the last 15 years has been analyzed with the FAO data for the total catch (fisheries and culture). By comparison of the two statistics for the same year (1986), the fisheries represented only 17% for oysters and 16% for mussels. Fig.... |
Tipo: Text |
Palavras-chave: Culture; Mussels; Oysters; Panel report. |
Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/1990/publication-3020.pdf |
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Maurer, Daniele; Borel, Michel. |
Les conditions très favorables à la reproduction de l'huître dans le bassin d'Arcachon, lui ont donné traditionnellement une vocation de centre de captage. Cette activité, très perturbée durant 5 années consécutives (peintures antisalissure à base d'organostanniques), a retrouvé son cours normal depuis 1982. Il est donc apparu intéressant de faire le point sur l'importance du captage réalisé dans le bassin, du fait de ses répercussions à la fois sur la vente de naissains et sur le recrutement de la population de Crassostrea gigas en élevage. Les estimations ont été menées durant 5 années, de 1985 à 1989, selon différents plans d'échantillonnage. |
Tipo: Text |
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Ano: 1990 |
URL: http://archimer.ifremer.fr/doc/00081/19185/16780.pdf |
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Robert, Rene; Maurer, Daniele. |
A new method of oyster cultivation, the Stanway oyster cylinder, has been experimented in the basin of Arcachon since the autumn of 1989. The first observations on three species of juvenile bivalves showed that this system could be successfully used with the Japanese oyster Crassostrea gigas . A comparative study of the growth of this last species, reared in cylinders and oyster bags, has been carried out since spring 1990. The first results showed that the growth of juveniles and 18 months old oysters in cylinders is not as good as in bags. On the other hand, mortality did not differ between both techniques: less than 3%. This new system seems to be less efficient than the traditional French way of rearing oysters. However, an improvement in the quality... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Bivalvia; Juveniles; Oyster culture; Growth; Rearing. |
Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/acte-917.pdf |
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Robert, Rene; Trut, Gilles; Borel, Michel; Maurer, Daniele. |
The Stanway cylinder was tested in the bay of Arcachon from September 1989 to August 1991. Trials were mainly performed on the Japanese oyster Crassostrea gigas in a wind-exposed area. The seed, spat, 18 month old oysters development and fattening of 2 year old oysters were studied. Compared to plastic bags the Stanway cylinder has high positive effects on survival and growth of Crassostrea gigas seed. It also has positive effects on commercial sized Crassostrea gigas fattening. Nevertheless, the cylinder has negative effects on the growth of Crassostrea gigas spat and 18 month old oysters, except for width. However, oyster quality is greatly improve : higher condition index, higher carbohydrate contents and higher shell densities were recorded. Because... |
Tipo: Text |
Palavras-chave: Bay of Arcachon; Culture methods; Growth; Crassostrea gigas; Bassin d'Arcachon; Technique d'élevage; Croissance; Crassostrea gigas. |
Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/rapport-1644.pdf |
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Gerard, Andre; Naciri, Yamama; Peignon, Jean-marie; Ledu, Christophe; Phelipot, Pascal; Baud, Jean-pierre; Nourry, Max; Haure, Joel; Coatanea, Denis; Oheix, Jocelyne; Vercelli, Catherine; Chabirand, Jean-michel; Borel, Michel; Maurer, Daniele; Heurtebise, Serge; Garnier, Jacqueline; Martin, Anne-genevieve; Tige, Gilbert; Mazurie, Joseph; Langlade, Aime. |
Cette réunion des membres du Réseau Génétique Mollusques avait pour objet de faire un bilan provisoire des actions en cours et surtout de mettre en place les protocoles et les calendriers du début de l'année 1994. La première demi-journée a été réservée à un exposé de Yamama NACIRI sur les bases de la Génétique Quantitative et ses applications dans le cadre des programmes de sélection des mollusques.La deuxième demi-journée a été consacrée au bilan des actions de 1993. Les représentants de chaque site, intervenant dans une opération du réseau en 1993, ont fait une présentation orale de leurs résultats. Un résumé de chaque intervention vous est fourni dans ce document. Il est important de souligner que tous ces bilans sont provisoires, en premier lieu parce... |
Tipo: Text |
Palavras-chave: Génétique; Sélection génétique; Huître plate; Ostrea edulis; Croissance; Génétique population. |
Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00049/15982/13425.pdf |
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Gerard, Andre; Naciri, Yamama; Peignon, Jean-marie; Ledu, Christophe; Phelipot, Pascal; Baud, Jean-pierre; Nourry, Max; Haure, Joel; Heurtebise, Serge; Garnier, Jacqueline; Martin, Anne-genevieve; Claude, Serge; Langlade, Aime; Joly, Jean-pierre; Goulletquer, Philippe; Ruelle, Francois; Coatanea, Denis; Oheix, Jocelyne; Vercelli, Catherine; Chabirand, Jean-michel; Maurer, Daniele; Borel, Michel; Cardinal, Mireille; Cornet, Josiane; Le Pennec, Marcel; Le Mercier, A.. |
This fifth part of the polyploidisation program reports the experiments that were conducted in 1993 and that were devoted to : - monitoring growth performance of Ostrea edulis diploids and triploids in La Trinité sur Mer and Palavas - monitoring growth performance of Crassostrea gigas diploids and triploids in Port en Bessin, Marennes Oleron (2 locations), Arcachon and Palavas - comparative study of gametogenesis for C. gigas diploids and triploids - comparative study of C. gigas diploids and triploids using sensorial analysis At the end of fifth year, it was clear that triploids are advantageous although such a statement must be moderated according to locations. The gametogenesis stydy showed that triploidy is associated with partial to complete... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Ostrea edulis; Cytogenetics; Polyploidy; Crassostra gigas; Ostrea edulis; Cytogénétique; Polyploïdie. |
Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/1994/rapport-3860.PDF |
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Registros recuperados: 81 | |
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