Consulta: creatorFacets:"Cochennec, Nathalie"
Registros recuperados: 57
Data/hora: 05/06/2024 11:18:54

Bilan 1998 du réseau REPAMO - Réseau National de Surveillance zoosanitaire des mollusques marins
Provedor de dados: 5
Autores: Thebault, Anne; Martin, Anne-genevieve; Le Coguic, Yvette; Hirata, Toshio; Tige, Gilbert; Pichot, Yves; Chollet, Bruno; Cochennec, Nathalie; Renault, Tristan.
Le réseau REPAMO répond à plusieurs objectifs, définis dans différentes Directives Européennes: prévenir et détecter l'introduction et la propagation d'un agent pathogène émergent, réémergent ou exotique pour les productions de coquillages d'intérêt commercial en France, surveiller l'évolution des maladies à déclaration obligatoire, surveiller les échanges avec nos partenaires commerciaux. Le fonctionnement repose sur la collaboration entre les professionnels, la DPMCM, les laboratoires côtiers d'IFREMER, et trois cellules d'analyses. Les prélèvements et les outils diagnostiques choisis dépendent des différents objectifs. Le suivi est fait sur des populations sauvages et cultivées du littoral français. Le nombre d'analyses progresse régulièrement grâce à...
Tipo: Text
Palavras-chave: Réseau surveillance; Pathologie; Mortalités; Mollusques marins.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00098/20904/18523.pdf

Herpesviruses associated with mortalities among Pacific oyster, Crassostrea gigas, in France-Comparative study
Provedor de dados: 5
Autores: Renault, Tristan; Le Deuff, Rose-marie; Cochennec, Nathalie; Maffart, Patricia.
Sporadic mortalities were reported in june and july of 1992 and 1993 among batches of hatchery-reared larval Pacifie oyster, Crassastrea gigas, and at the beginning of July and in August of 1993 among five batches of 3-7 month old young spats, C. gigas. Observations with transmission electron microscope showed the presence of herpes-like virus particles in infected larvae and young spats. The viruses observed in diseased larvae and affected young spat oysters were very similar. Elevated temperature and crowding may increase susceptibility of oysters to these herpes-like virus infections.
Tipo: Text
Palavras-chave: Spat; Larvae; Crassostrea gigas; Pacific oysters; Mortality; Herpes like virus; Naissain; Larve; Crassostrea gigas; Huître japonaise; Mortalités; Herpès like virus.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-2898.pdf

Caractérisation de bactéries pathogènes, Vibrio splendidus, isolées de bivalves marins
Provedor de dados: 5
Autores: Gay, Melanie; Waechter, Magali; Lambert, Christophe; Escoubas, Jean-michel; Cochennec, Nathalie; Nicolas, Jean-louis; Berthe, Franck; Le Roux, Frédérique.
Nowadays, cupped oyster, Crassostrea gigas, production is the main shellfish production in France. Spats cultivated on most farms are usually collected in the wild, but hatchery spats are becoming more numerous, and represent around 10% of today's cultivated spats. During the summer period, when the temperatures are higher, high mortality rates have been regularly observed in cupped in oyster C. gigas (60 to 100%) spats since 1991, both in hatcheries-nurseries and in their natural habitat. Over the last five years, these episodes have become a big concern for all the professionals.
Tipo: Text
Palavras-chave: Crassostrea gigas; Pathogène; Vibrio splendidus; Bactériologie.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3277.pdf

Mikrocytos roughleyi taxonomic affiliation leads to the genus Bonamia (Haplosporidia)
Provedor de dados: 5
Autores: Cochennec, Nathalie; Reece, K.; Berthe, Franck; Hine, Mike.
Microcell-type parasites of oysters are associated with a complex of diseases in different oyster species around the world. The etiological agents are protists of very small size that are very difficult to characterize taxonomically. Associated lesions may vary according to the host species, and their occurrence may be related to variations in tissue structure. Lesion morphology cannot be used to distinguish the different agents involved. Ultrastructural observations on Mikrocytos roughleyi revealed similarities with Bonamia spp., particularly in regard to the presence of electron-dense haplosporosomes and mitochondria, whose absence from M mackini also indicate that M roughleyi and M mackini are not congeneric. A partial small subunit (ssu) rRNA gene...
Tipo: Text
Palavras-chave: Small subunit rDNA; Taxonomy; Microcell; Bonamosis; Saccostrea glomerata; Mikrocytos roughleyi.
Ano: 2003
URL: https://archimer.ifremer.fr/doc/2003/publication-2816.pdf

La Bonamiose : études des mécanismes cellulaires de défense de l'huître plate, Ostrea edulis, vis à vis du parasite Bonamia ostreae
Provedor de dados: 5
Autores: Cochennec, Nathalie; Renault, Tristan; Chollet, Bruno.
Bonamiosis—a disease caused by a protozoan parasite, Bonamia ostreae—was detected for the first time in Brittany in 1979 in conjunction with a massive mortality event. Since then, the disease has spread to all French oyster farming areas, and then throughout Europe.
Tipo: Text
Palavras-chave: Pathologie; Ostrea edulis; Bonamia ostreae.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3241.pdf

Evolution de la situation épizootiologique en Bretagne en 1983 suite au développement de Bonamia ostreae
Provedor de dados: 5
Autores: Tige, Gilbert; Grizel, Henri; Cochennec, Nathalie; Rabouin, Marie-agnès.
Bonamia ostreae diseease is always present in Brittany in the different farming areaa except few free natural oysters beds. Yet Bonamiose disease have not increased in the Bay of Cancale on oysters initialy very few parasited. The technical modifications of rearing and the eradication on sick oysters could explain this situation.
Tipo: Text
Palavras-chave: France; Bretagne; Pathologie; Parasite; Bonamiose; Bonamia ostreae.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-4971.PDF

Selecting flat oysters, Ostrea edulis, for survival against the parasite Bonamia ostreae : assessment of the resistance of a first selected generation
Provedor de dados: 5
Autores: Martin, Anne-genevieve; Gerard, Andre; Cochennec, Nathalie; Langlade, Aime.
In 1989, a selected strain of flat oyster. Ostrea edulis, was produced from breeders that survived Bonamia ostreae and that were over selected by injection of purified parasites. This generation (G 1) was compared to native oysters which had settled during the same year. After a growing period of 21 months,  the oysters were tested according to three procedures: exposure to natural infection in an intertidal area, maintenance at the laboratory in tanks near heavily infested oysters, injection of parasites. The test lasted 7 months. In each procedure, oysters of the first generation (G1) showed a better survival rate than control oysters (72 to 94% versus 48 to 66%). On the other hand, the highest mortalities were observed among injected oysters (G1 and...
Tipo: Text
Palavras-chave: Genetics; Ostrea edulis; Bonamia ostreae; Parasite resistance.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/acte-3201.pdf

Contrat de Plan Etat Région Poitou-Charentes 1994-1998. Convention 96 RPC R70 - Programme Pathologie - Rapport Scientifique année 1996
Provedor de dados: 5
Autores: Renault, Tristan; Berthe, Franck; Chollet, Bruno; Cochennec, Nathalie; Haffner, Philippe; Le Deuff, Rose-marie; Lipart, Cecile; Thebault, Anne.
Le but de ce programme pathologie est de rechercher et d'étudier les agents pathogènes connus et inconnus chez les mollusques bivalves marins, plus particulièrement chez l'huître creuse, Crassostrea gigas, afin d'identifier d'éventuels agents causant des mortalités, de proposer des mesures prophylactiques et de définir des conditions zootechniques permettant aux professionnels de limiter l'impact des maladies sur leur cheptel. La présence de maladies, chez les mollusques bivalves marins dont l'impact socio économique peut être catastrophique pour les productions conchylicoles, et l'accroissement des échanges de produits d'aquaculture entre les pays de la CEE et avec les pays tiers nécessitent le renforcement des recherches dans les domaines de la...
Tipo: Text
Palavras-chave: Pathologie; Pathogènes; Virus; Herpès virus; Crassostrea gigas; Diagnostic; Herpesviridae.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/00043/15452/12827.pdf

Development of an antiseptic procedure to improve retention rates during the grafting process of black-lip oyster, Pinctada margaritifera
Provedor de dados: 5
Autores: Cochennec, Nathalie; Haffner, Philippe; Levy, Peva; Saulnier, Denis; Fougerouse, A.; Langy, Sandra.
In French Polynesia, black pearl cultivation now takes place on about 30 of the 118 atolls or islands. This activity has largely replaced copra, coconut oil and fishing as a source of income. Around 1,000 pearl farms, generally small ones of less than 5 ha, are registered. The pearl farms are mainly owned by families. In 1998, about 7,000 persons were employed in theentire pearl industry, from production to retailing. In value, this activity represents the first exportation of French Polynesian products. From 1988 to date, exports increased exponentially before leveling. Starting with less than two kilograms in 1972, exports have now stabilized at Il tons of "black" pearls.
Tipo: Text
Palavras-chave: Vibrio; Microbiology; Grafting process; Pinctada margaritifera.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-4928.PDF

Concomitant herpes-like virus infections in hatchery-reared larvae and nursery-cultured spat Crassostrea gigas and Ostrea edulis
Provedor de dados: 5
Autores: Renault, Tristan; Le Deuff, Rose-marie; Chollet, Bruno; Cochennec, Nathalie; Gerard, Andre.
Concomitant sporadic high mortalities were reported in France in May 1994 among batches of hatchery-reared larval Pacific oysters Crassostrea gigas and European flat oysters Ostrea edulis in 2 hatcheries, and in June and July 1994 among batches of cultured spat of both species in a shellfish nursery. Histological observation showed the presence of cellular abnormalities in moribund animals. Transmission electron microscopy revealed the presence of herpes-like virus particles in infected larvae and spat of both oyster species. This is the first description of a herpes-like virus infection in larval O.. edulis. Viruses observed in diseased larvae and spat of both species are similar with respect to ultrastructure and morphogenesis, They were detected...
Tipo: Text
Palavras-chave: Apoptosis; Virus replication; Concomitant infection; Oyster mortality; Crassostrea gigas; Pacific oyster; Ostrea edulis; European flat oyster; Herpes like virus.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-820.pdf

Bonamia-like parasite found in the Suminoe oyster Crassostea rivularis reared in France
Provedor de dados: 5
Autores: Cochennec, Nathalie; Renault, Tristan; Boudry, Pierre; Chollet, Bruno; Gerard, Andre.
Considering the economic importance of the Pacific oyster Crassostrea gigas to the French shellfish industry, the appearance of major diseases in this species could cause dramatic decreases in production Suminoe oysters, of the non-indigenous species Crassostrea rivularis (Gould), were introduced into France to test their ability to adapt to local conditions. These oysters were imported after careful examination, and were maintained in laboratory quarantine. Some mortalities occurred 7 mo after importation. Histological and electron microscope examinations of 9 dead specimens revealed a parasite presumed to be a Bonamia-like protozoan. This is the first report concerning a parasite of the genus Bonamia in a species belonging to the genus Crassostrea. Thus,...
Tipo: Text
Palavras-chave: Bonamia like parasite; Bonamiosis; Simunoe oyster; Crassostrea rivularis.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-2904.pdf

Contribution à l'étude de mollusques marins : Iridovirus-like et Herpèsvirus-like. Description, caractérisation biochimique, cycle de multiplication viral, diagnostic et étude épidémiologique
Provedor de dados: 5
Autores: Renault, Tristan; Le Deuff, Rose-marie; Cochennec, Nathalie; Chollet, Bruno; Maffart, Patricia.
Among the marine molluscs, Pacifie oyster, Crassostrea gigas, is actually the most reared specie in the world. Noticely in France, where it was imported between 1960 and 1970, and replaced by Portuguese oyster, Crassostrea angulata, which specie was decimated during this period because of iridoviruses. Uncontroled introductions of new species may however be hazardous. Indeed, they might be responsible for the appearance and the dissemination of new diseases of bivalve molluscs in importing country. In addition to these observations, the quasi monobreeding of Pacific oyster in France enhances the necessity to develop research concerning the diagnosis of pathologies affecting this specie, namely the diagnosis of viral diseases. Several families of viruses...
Tipo: Text
Palavras-chave: Mollusques; Crassostrea gigas; Pathologie; Iridovirus; Herpèsvirus; Diagnostic; Molluscs; Crassostrea gigas; Pathology; Iridovirus; Herpesvirus; Diagnosis.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00041/15230/12548.pdf

Juvenile oyster disease (JOD) in American oysters, Crassostrea virginica, reared in France. Detection of abnormal calcium deposits in gill and mantle tissues
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Chollet, Bruno; Maffart, Patricia.
Progeny of Crassostrea virginica oysters, introduced into France in 1992, were reared during 1992 and 1993, to test their growth performances. These assays were performed to investigate the possible replacement of Crassostrea gigas with a non indigenous species, Crassostrea virginica. During the summer of 1993, sporadic mass mortalities (80-90%) occurred among young, Crassastrea virginica, oysters reared in the IFREMER nursery in La Tremblade (Charente Maritime).
Tipo: Text
Palavras-chave: Histology; Crassostrea virginica; Mortality; Oysters.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/acte-2975.pdf

Microcell parasites of oysters: Recent insights and future trends
Provedor de dados: 5
Autores: Carnegie, Ryan; Cochennec, Nathalie.
Our understanding of the microcell oyster parasites of the genera Bonamia and Mikrocytos has expanded in recent years with the application of ultrastructural and especially molecular biological research approaches. Molecular phylogenetic analyses of SSU rRNA genes have united three species, Bonamia ostreae, Bonamia exitiosa, and Mikrocytos (now Bonamia) roughleyi, in a microcell clade within the Haplosporidia, supporting both early and recent ultrastructural observations. Ultrastructural and molecular phylogenetic evidence has emerged that Mikrocytos mackini, on the other hand, is a unique protist with unusual adaptations for a parasitic existence. DNA probes and polymerase chain reaction (PCR) assays promise new insights into the life cycles,...
Tipo: Text
Palavras-chave: Mikrocytos; Bonamia; Microcell.
Ano: 2004
URL: https://archimer.ifremer.fr/doc/2004/publication-408.pdf

Historique, expériences en cours et perspectives du programme de sélection de l'huître plate Ostrea edulis pour la résistance à la bonamiose
Provedor de dados: 5
Autores: Barre, Marc; Naciri, Yamama; Boudry, Pierre; Goyard, Emmanuel; Launey, Sophie; Cochennec, Nathalie; Heurtebise, Serge; Ledu, Christophe; Phelipot, Pascal; Gerard, Andre.
The Aquaculture and Pathological Genetics (GAP) laboratory at La Tremblade has been monitoring three populations of European flat oyster since 1985 or 1989 under selection for higher survival rates in the presence of the parasite Bonamia ostrea. One selection cycle (1985 population) or two (1989 populations) were carried out by mass selection by placing the oysters for several years in a highly infested zone, and then harvesting spawns from survivors.
Tipo: Text
Palavras-chave: Huîtres plates; Génétique; Selection génétique; Ostrea edulis.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3244.pdf

Epidémiologie moléculaire des espèces Marteilia en Europe
Provedor de dados: 5
Autores: Le Roux, Frédérique; Audemard, Corinne; Cochennec, Nathalie; Thebault, Anne; Berthe, Franck.
Responsible for massive epizootics, the Marteilia type parasites are very dangerous infectious agents for oysters. As a matter of fact, in France the spreading out of the parasitosis caused by Marteilia refringens disturbed dangerously the flat oyster, Ostrea edulis, production; destroying a large percentage of the farms on the Atlantic coast. The fight against marteiliose implies a good management of the contamination risk, that is to say the identification of the parasite(s), the characterization of the host(s), vector(s) or reservoir(s) and the understanding of the parasite's transmission mode.
Tipo: Text
Palavras-chave: Bivalves; Biologie Moléculaire; Marteilia refringens; Epidémiologie.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3271.pdf

Contrat de Plan Etat Région Poitou-Charentes 1994-1998. Convention 95 RPC R 62 - Programme Pathologie - Rapport Scientifique année 1995
Provedor de dados: 5
Autores: Renault, Tristan; Berthe, Franck; Chollet, Bruno; Cochennec, Nathalie; Haffner, Philippe; Le Deuff, Rose-marie; Thuillier, Benoit.
Le but de ce programme pathologie est de rechercher et d'étudier les agents pathogènes connus et inconnus chez les mollusques bivalves marins, plus particulièrement chez l'huître creuse, Crassostrea gigas, afin d'identifier d'éventuels agents causant des mortalités, de proposer des mesures prophylactiques et de définir des conditions zootechniques permettant aux professionnels de limiter l'impact des maladies sur leur cheptel. La présence de maladies, chez les mollusques bivalves marins dont l'impact socio économique peut être catastrophique pour les productions conchylicoles, et l'accroissement des échanges de produits d'aquaculture entre les pays de la CEE et avec les pays tiers nécessitent le renforcement des recherches dans les domaines de la...
Tipo: Text
Palavras-chave: Pathologie; Pathogènes; Virus; Herpès virus; Crassostrea gigas; Diagnostic; Herpesviridae.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00043/15453/12828.pdf

Le suivi de l'état des récifs coralliens de Polynésie Française et leur récente évolution
Provedor de dados: 5
Autores: Salvat, B; Aubanel, A; Adjeroud, M; Bouisset, P; Calmet, D; Chancerelle, Y; Cochennec, Nathalie; Davies, N; Fougerousse, A; Galzin, R; Lagouy, E; Lo, C; Monier, Christele; Ponsonnet, C; Remoissenet, G; Schneider, D; Stein, A; Tatarata, M; Villiers, L.
Monitoring of French Polynesia coral reefs and their recent development.-French Polynesia, consisting of 118 islands in the centre of the Pacific Ocean, has more than 15 000 km(2) of reefs and lagoons managed by the local government. Tourism and pearl culture are the two main economic resources of the country. Polynesian coral reefs are extremely diverse and are among those for which we have thorough knowledge. The exploitation of local resources has been recorded for multiple decades and includes : coral materials, fishing, harvest and export of mother-of-pearl molluscs, pearl production, and ornamental fish. All over the country, many monitoring programmes have been launched to measure the health of reefs and the natural and anthropogenic perturbations...
Tipo: Text
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4558.pdf

Chlamydia-like organisms in ctenidia and mantle cells of the Japanese oyster Crassostrea ggias from the French Atlantic coast
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie.
Grossly visible lesions of the ctenidia and occasional mortalities in Japanese oyster Crassostrea gigas from the Atlantic French coast were reported in 1992-1993. From August 1992 to March 1993, 235 living oysters were collected to determine the cause of tissue lesions and mortalities. Microscopical examination of fixed, stained sections revealed that 53 2% of these oysters had ctenidia and mantle lesions associated with irregular basophllic and Feulgen positive cytoplasmic inclusion bodies. Ultrastructurally, the infectious agent was a chlamydia-like organism. Indirect fluorescent and peroxidase conjugated antibody tests suggested that this agent might share common antigens with the prokaryotic agent Chlamydia psittaci, strain ovis
Tipo: Text
Palavras-chave: Mantle; Ctenidia; Chlamydia like organisms; Pacific oyster; Crassostrea gigas.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/publication-2896.pdf

Essai d'acclimatation de Crassostrea virginica et performances biologiques comparées avec Crassostrea gigas (2ème partie)
Provedor de dados: 5
Autores: Gerard, Andre; Naciri, Yamama; Peignon, Jean-marie; Ledu, Christophe; Phelipot, Pascal; Baud, Jean-pierre; Heurtebise, Serge; Nourry, Max; Renault, Tristan; Cochennec, Nathalie; Zanette, Yvan; Blachier, Philippe.
Deuxième volet du programme d'essai d'acclimatation de l'huître américaine Crassostrea virginica, ce rapport présente les actions et les résultats de l'année 1993 qui a été consacrée au suivi des performances comparées de croissance des populations de C. gigas et C. virginica produites en 1992, ceci en trois sites différents: • dans le bassin de Marennes-Oléron en claire et sur estran, à la station IFREMER de Bouin en élevage intensif, au CREAA sur l'Ile d'Oléron en marais extensif. Au terme de cette seconde année d'étude, il est d'ores et déjà possible d'affirmer que que la souche anglaise de C. virginica étudiée ne présente pas de caractéristiques de croissance susceptibles de la rendre compétitive par rapport au témoin Crassostrea gigas et cela d'autant...
Tipo: Text
Palavras-chave: Mollusques; Acclimatation; Crassostrea virginica; Crassostrea gigas; Génétique; Pathologie.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00077/18846/16419.pdf

Les parasites du groupe "Mikrocell" : Qui est qui?
Provedor de dados: 5
Autores: Cochennec, Nathalie; Le Roux, Frédérique; Berthe, Franck; Thebault, Anne.
Bonamiose, a disease caused by the protozoa Bonamia ostreae, has destroyed the flat oyster Ostrea edulis production, in France but also in Europe and in the United States since 1979. Another species of Bonamia has been monitored in New-Zealand, in Australia and lately in Chile. In Canada and Australia, two other parasites have been described in cupped oyster: Mikrocytos mackini and Mikrocytos roughleyi. All these small size protozoa are grouped under the name "Mikrocell". For most of them, light and electronic microscope descriptions have been realised. Based on those criteria, different taxonomic positions have been proposed. However, these analysis are still questioned today.
Tipo: Text
Palavras-chave: Bivalves; Haplosporidia; Parasites; Pathologie.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3270.pdf

Pathology of cultured paua Haliotis iris infected with a novel haplosporidian parasite, with some observations on the course of disease
Provedor de dados: 5
Autores: Diggles, Bk; Nichol, J; Hine, Pm; Wakefield, S; Cochennec, Nathalie; Roberts, Rd; Friedman, Cs.
Mortalities among juvenile paua Haliotis iris Martyn 1784 in a commercial culture facility were reported in April 2000. Histology of moribund paua showed heavy systemic infections of a uni- to multi-nucleate stage of a novel organism later confirmed by transmission electron microscopy (TEM) and molecular studies to be a haplosporidian. Multinucleate plasmodia up to 25 &amp;#956;m diameter with up to 17 nuclei were detectable in wet preparations of hemolymph from heavily infected paua. The presence of the haplosporidian in the affected facility was associated with mortalities of slow growing 'runt' paua during the summer months. Total mortalities in affected raceways 6 mo after mortalities began were between 82.5 and 90%. Heavily infected paua exhibited...
Tipo: Text
Palavras-chave: Haplosporidia; Abalone; Aquaculture; Pathology; Disease; New Zealand.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/publication-2783.pdf

A direct monoclonal antibody sandwich immunoassay for detection of Bonamia ostreae (Ascetospora) in hemolymph samples of the flat oyster Ostrea edulis (Mollusca : Bivalvia)
Provedor de dados: 5
Autores: Cochennec, Nathalie; Hervio, Dominique; Panatier, B; Boulo, Viviane; Mialhe, Eric; Rogier, H; Grizel, Henri; Paolucci, F.
Currently recognition of molluscan diseases relies heavily upon light microscopic examination of stained histological sections of molluscan tissues Such histopathological methods are time consuming and relatively inefficient In the study of ongoing epizootics Alternatively, more effluent investigative tools are needed to accelerate disease recognition and quantification Such methods are needed to prevent control and eradicate molluscan diseases This paper reports the development of a direct sandwich enzyme-lmmunosorbent assay (ELISA) for the ascetosporan intrahemocytic parasite Bonamiao ostreae of the flat oyster Ostrea edulis. Bonamiasis is a commercially important epizootic disease of oysters A Bonamia-specific monoclonal antibody is employed in the...
Tipo: Text
Ano: 1992
URL: http://archimer.ifremer.fr/doc/1992/publication-2765.pdf

Bonamia ostreae, parasite of the European flat oyster, Ostrea edulis, does not experimentally infect the Japanese oyster, Crassostrea gigas
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Grizel, Henri.
The protozoan Bonamia ostreae (Ascetospora) is the etiological agent of bonamiosis, or hemocyte disease of the European fiat oyster, Ostrea edulis (Pichot et al., 1980). Since this infection was first reported from the coast of Brittany (Comps et al., 1980), the parasite has spread rapidly along the French Atlantic coasts (Grizel &amp; Tigé, 1982), and in the European countries including the UK, Holland, lreland and Spain (Bannister &amp; Key, 1982; Van Banning, 1982; Polanco et al., 1984). Under the EEC Council Directive 91/67, this parasitic protozoan is included in list II of Annex A. Serious pathogen agents for molluscs that should be obligatorily declared are placed in this list
Tipo: Text
Palavras-chave: Infection; Protozoan; Oyster; Ostrea edulis; Bonamia ostreae.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/publication-2892.pdf

Etude du virus de type herpes observé chez les huîtres
Provedor de dados: 5
Autores: Le Deuff, Rose-marie; Lipart, Cecile; Chollet, Bruno; Haffner, Philippe; Delsert, Claude; Cochennec, Nathalie; Renault, Tristan.
Since 1991, sporadic, but high mortality in larvae of the Pacific oyster (Crassostrea gigas) has been observed during the summer in various French hatcheries. This mortality was concomitant with the detection of a virus by transmission electron microscopy. This virus, by virtue of its morphological characteristics and developmental cycle, seems to belong to the Herpesviridae family. The pathogenicity of this viral agent has been demonstrated in the laboratory by experimentally induced mortality on healthy larvae. Moreover, concomitant mortality has been reported in larvae of Crassostrea gigas and Ostrea edulis reared in the same tanks, with detection of a herpes-type virus.
Tipo: Text
Palavras-chave: Virus; Herpeviridae; Pathologie; Crassostrea gigas.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3248.pdf

First report of a Mikrocytos-like parasite in European oysters Ostrea edulis from Canada after transport and quarantine in France
Provedor de dados: 5
Autores: Gagne, N; Cochennec, Nathalie; Stephenson, M; Mcgladdery, S; Meyer, G; Bower, S.
As part of a disease resistance experiment, 112 apparently healthy European flat oysters Ostrea edulis L. were exported from Canada (Nova Scotia) into France to test their susceptibility to Bonamia ostreae infection. Twelve oysters died in transit and 17 others died within 2 wk of laboratory quarantine acclimation. All oysters were examined histologically, and the 17 that died during quarantine were assayed for microcells (Bonamia sp. and Mikrocytos mackini) using molecular techniques. A microcell parasite was detected in the connective tissue of 5 of the 112 oysters. Morphological appearance, tissue affinity and molecular characterization through PCR, in situ hybridization (ISH), fluorescence in situ hybridization (FISH) and sequencing revealed a protist...
Tipo: Text
Palavras-chave: Histology; PCR; In situ hybridization; Ostrea edulis; Mikrocytos.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4475.pdf

Bonamia-like parasite found in the Suminoe oyster Crassostrea rivularis reared in France
Provedor de dados: 5
Autores: Cochennec, Nathalie; Renault, Tristan; Boudry, Pierre; Chollet, Bruno; Gerard, Andre.
Considering the economic importance of the Pacific oyster Crassostrea gigas to the French shellfish industry, the appearance of major diseases in this species could cause dramatic decreases in production. Suminoe oysters, of the non-indigenous species Crassostrea rivularis (Gould), were introduced into France to test their ability to adapt to local conditions. These oysters were imported after careful examination, and were maintained in laboratory quarantine. Some mortalities occurred 7 mo after importation. Histological and electron microscope examinations of 9 dead specimens revealed a parasite presumed to be a Bonamia-Like protozoan. This is the first report concerning a parasite of the genus Bonamia in a species belonging to the genus Crassostrea....
Tipo: Text
Palavras-chave: Crassostrea rivularis; Suminoe oyster; Bonamiosis; Bonamia-like parasite.
Ano: 1998
URL: https://archimer.ifremer.fr/doc/00446/55795/62652.pdf

Bilan 1999 du Réseau REPAMO - Réseau National de Surveillance zoosanitaire des Mollusques marins
Provedor de dados: 5
Autores: Thebault, Anne; Martin, Anne-genevieve; Le Coguic, Yvette; Hirata, Toshio; Tige, Gilbert; Pichot, Yves; Grizel, Henri; Berthe, Franck; Cochennec, Nathalie; Renault, Tristan; Le Roux, Frederique.
Le réseau REPAMO (Réseau de Pathologie des Mollusques) est un réseau de santé animale, qui s'occupe des coquillages marins du littoral français métropolitain. Les mollusques marins des côtes françaises représentent une ressource par la pêche, mais sont surtout une part importante de l'aquaculture. Les pertes liées aux maladies dans ce domaine d'activité sont aujourd'hui considérées comme l'un des principaux facteurs limitants de son développement au niveau mondial. Deux exemples récents suffisent à illustrer ce danger pour l'ostréiculture française : • La culture de l''huître plate Ostrea edulis, déjà atteinte par un parasite, Marteilia refringens, est passée en quelques années de 20 000 tonnes à 1800 tonnes, suite à une épizootie. En effet à la fin des...
Tipo: Text
Palavras-chave: Réseau surveillance; Pathologie; Mollusques bivalves; Mortalité.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00098/20903/18522.pdf

Ecophysiological study on the Pacific oyster Crassostrea gigas naturally infected by a Chlamydia-like microorganism : effect of infection level and diet on oyster physiological responses
Provedor de dados: 5
Autores: Soletchnik, Patrick; Goulletquer, Philippe; Cochennec, Nathalie; Renault, Tristan; Geairon, Philippe.
A population of Pacific ovsters, Crassostrea gigas, infected with a Chlamydia-like procaryote was reared to compare infection trends under three different feeding conditions: a starved condition, an  intermediate condition with a diet of Skeletonema costatllm, and a mixed algal diet. Several physiological and pathological criteriJ: presence of gill abnormality; microscopic examination, basophilic intracytoplasmic inclusions, Feulgen reaction; condition index, filtration, food consumptiQn; fecal production and respiration were used to compare the various modalities one month after the initiation of the experiment. The Irodality of starved oysters showed reduce physiological performances in terms of scope for growth and condition index compared to oysters...
Tipo: Text
Palavras-chave: Pathogen; Chlamydia; Procaryote; Crassostrea gigas; Oyster; Ecophysiology; Pathogène; Chlamydia; Procaryote; Crassostrea gigas; Huître; Ecophysiologie.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-2741.pdf

Rapport sur la situation zoosanitaire du cheptel Crassostrea gigas : cas du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Grizel, Henri; Renault, Tristan; Cochennec, Nathalie; Tige, Gilbert; Audic, Guylaine; Pichot, Yves; Chollet, Bruno; Goulletquer, Philippe; Soletchnik, Patrick; Geairon, Philippe; Prou, Jean.
Le cheptel d'huîtres creuses, Crassostrea gigas, du Bassin de Marennes-Oléron a subi ces dernières années des morta lités (mai 88, mai 91, été 1992 et hiver 92-93). Les examens histopathologiques pratiqués durant celles-ci n'ont pas permis de déceler d'agents pathogènes. Les causes avaient été attribuées essentiellement, pour les premiers cas, à un manque de nourriture corrélé avec des conditions de sécheresse (donc un manque d'apport d'eau douce pour le bassin) et à des surcharges trop importantes des biomasses de fiItreurs, huîtres y compris. L'explication du dernier cas de mortalité survenue au cours de l'hiver serait d'un autre ordre: l'abaissement brutal des salinités, notamment dans les claires où étaient épurées soit des huîtres natives fragilisées,...
Tipo: Text
Palavras-chave: Etude zoosanitaire; Mortalité; Epidémiologie; Pathologie; Marennes Oléron.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00050/16152/13635.pdf

La Bonamiose : mise au point de réactifs pour le diagnostic et étude des mécanismes cellulaies de défense développés par l'hôte, l'huître plate, Ostrea edulis
Provedor de dados: 5
Autores: Cochennec, Nathalie.
Une partie de ce travail, a consisté à développer quelques techniques pour la caractérisation et le diagnostic de ce protozoaire. Ainsi, après avoir optimisé le protocole de purification de B. ostreae, il a été possible de définir quelques unes des propriétés des protéines de ce parasite dont la connaissance s'avère nécessaire pour le choix de cibles potentielles d'un diagnostic. Cette caractérisation des protéines a été réalisée par la description des profils électrophorétiques en SDS-PAGE, et par la recherche des glycoprotéines à l'aide d'une lectine. Nous nous sommes également attachés à la préparation d'anticorps polyclonaux spécifiques du parasite, dans l'optique de disposer d'une technique de diagnostic sensible, fiable et rapide. En outre, ce type...
Tipo: Text
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00408/51953/52588.pdf

Programme Pathologie - Rapport scientifique Année 1994 - Contrat de Plan Etat Région Poitou-Charentes 1994-1998 - Convention 94 RPC R 62
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Le Deuff, Rose-marie; Chollet, Bruno; Maffart, Patricia; Haffner, Philippe; Berthe, Franck; Thuillier, Benoit.
Le but de ce programme pathologie est de recherher et d'étudier les agents pathogènes connus et inconnus chez les mollusques bivalves marins, plus particulièrement chez l'huître creuse, Crassastrea gigas, afin d'identifier d'éventuels agents causant des mortalité, de proposer des mesures prophylactiques et de définir des conditions zootechniques permettant aux professionnels de limiter l'impact des maladies sur leur cheptel. La présence de maladies, chez les mollusques bivalves marins dont l'impact socioéconomique peut être catastrophique pour les productions conchylicoles, et l'accroissement des échanges de produits d'aquaculture entre les pays de la CEE et avec les pays tiers nécessitent le renforcement des recherches dans les domaines de la pathologie....
Tipo: Text
Palavras-chave: Pathologie; Agent pathogène; Infection; Virus; Herpèsvirus; Purification; Huître creuse; Crassostrea gigas.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00044/15502/12874.pdf

Molecular detection of the oyster parasite Mikrocytos mackini, and a preliminary phylogenetic analysis
Provedor de dados: 5
Autores: Carnegie, Ryan; Meyer, Gary; Blackbourn, Janice; Cochennec, Nathalie; Berthe, Franck; Bower, Susan.
The protistan parasite Mikrocytos mackini, the causative agent of Denman Island disease in the oyster Crassostrea gigas in British Columbia, Canada, is of wide concern because it can infect other oyster species and because its life cycle, mode of transmission, and origins are unknown. PCR and fluorescent in situ hybridization (FISH) assays were developed for M mackini, the PCR assay was validated against standard histopathological diagnosis, and a preliminary phylogenetic analysis of the M mackini small-subunit ribosomal RNA gene (SSU rDNA) was undertaken. A PCR designed specifically not to amplify host DNA generated a 544 bp SSU rDNA fragment from M mackini-infected oysters and enriched M. mackini cell isolates, but not from uninfected control oysters....
Tipo: Text
Palavras-chave: Fluorescent in situ hybridization; PCR validation; Mikrocytos mackini; Denman Island disease.
Ano: 2003
URL: https://archimer.ifremer.fr/doc/2003/publication-2814.pdf

Contrat de Plan Etat Région Poitou-Charentes 1994-1998. Convention 98 RPC R 7 - Programme Pathologie - Rapport Final année 1998
Provedor de dados: 5
Autores: Renault, Tristan; Berthe, Franck; Thebault, Anne; Lipart, Cecile; Chollet, Bruno; Cochennec, Nathalie; Haffner, Philippe.
Depuis 1991, des mortalités massives sporadiques sont rapportées, en France, de manière régulière chez des larves et des juvéniles de différentes espèces de mollusques bivalves marins. Certains de ces épisodes de mortalité ont pu être associés à la détection de virus. Ces derniers par leur morphologie, leur cycle de réplication et leur localisation ont été apparentés à la famille des Herpesviridae. Cependant, les outils de diagnostic disponibles jusqu'alors (histologie et microscopie électronique à transmission) n'étaient pas adaptés à l'étude de ces virus du fait de leur manque de spécificité et de la lourdeur de leur mise en oeuvre. Par ailleurs, se posait la question de l'implication des virus détectés dans les phénomènes de mortalité observés. En...
Tipo: Text
Palavras-chave: Pathologie; Pathogènes; Virus; Herpès virus; Crassostrea gigas; Diagnostic; Herpesviridae.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00043/15455/12830.pdf

Les réseaux d'épidémio-surveillance REPANUI et REPAMO
Provedor de dados: 5
Autores: Joly, Jean-pierre; Cochennec, Nathalie; Fougerouse, Angélique; Francois, Cyrille.
Created in 1992, the French network REPAMO is in charge of the surveillance and monitoring of the mollusc health status along the French coast according to European legislation. The missions of the network are the following: (1) the surveillance of notifiable diseases present in France, (2) the study of abnormal mortalities, (3) the surveillance of health status of cultivated and natural mollusc populations. The more recent network REPANUI has similar goals mainly focused on the pearl oyster health status to support the oyster farming industry in French Polynesia.
Tipo: Text
Palavras-chave: REPAMO; REPANUI; Perspective; Gestion; Organisation; Epidémiologie; Réseaux surveillance.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2978.pdf

Establishing causal link between an infectious agent and mortalities in marine molluscan aquaculture on the example of Bonamia ostreae and Herpèsvirosis in oysters : proposal of a causal grid analysis
Provedor de dados: 5
Autores: Thebault, Anne; Cochennec, Nathalie; Arzul, Isabelle; Renault, Tristan.
In marine molluscan aqauculture, infectious agents are regularly cited in literature associated with mass mortalities as emergin diseases, but the causal link is often based on very few argumeents. 24 ways to demonstrate causal links from epidemiolgical, ecological and marine pathology literature feasible for marine molluscs are given. Those criteria were applied to the ewample of Bonamia ostreae for Ostrea edulis and Herpesvirus for spats and larvae of Crassostrea gigas. Three principles could be applied in marine field for choosing criteria wich should be taken in priority : the demonstration must be given at three levels of organization, organ individual, population, the demonstration must keeps maximum epidemiological criterias, and then mixes...
Tipo: Text
Palavras-chave: Herpesvirus; Bonamia ostrea; Crassostrea gigas; Ostrea edulis; Marine pathology; Ecology; Epidemiology; Infectious agents; Molluscan aquaculture.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3341.pdf

Bonamia exitiosus n. sp (Haplosporidia) infecting flat oysters Ostrea chilensis in New Zealand
Provedor de dados: 5
Autores: Hine, P; Cochennec, Nathalie; Berthe, Franck.
Bonamia sp. is a pathogenic parasite that occurs in the haemocytes of dredge oysters Ostrea chilensis Philippi in New Zealand, Ultrastructurally it resembles other haplosporidians in the possession of haplosporosomes, haplosporogenesis, persistence of mitotic microtubules during interphase and of the nuclear envelope during mitosis, and occurrence of a diplokaryotic or multi-nucleate plasmodial stage. Another stage containing a large vacuole derived from enlargement of 1 or more mitochondria has not previously been described from other haplosporidians. It most closely resembles B, ostreae Pichot et al., 1979, which parasitises and is pathogenic in haemocytes of European flat oysters, O. edulis. However, B. ostreae is smaller and denser, and has fewer...
Tipo: Text
Palavras-chave: New Zealand; 18S rDNA; Ultrastructure; Ostrea chilensis; Bonamia exitiosus.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-818.pdf

Molecular characterisation of an Australian isolate of Bonamia exitiosa
Provedor de dados: 5
Autores: Corbeil, Serge; Arzul, Isabelle; Robert, Maeva; Berthe, Franck; Cochennec, Nathalie; Crane M, Mark.
An Australian (New South Wales) isolate of Bonamia was characterised at the molecular level by sequencing the 18S-ITS-1 region of the small subunit rRNA operon obtained from flat oysters Ostrea angasi shown to be infected by histological examination. Sequence data alignment with homologous genes from 2 other isolates of Bonamia (New Zealand and France) revealed high levels of nucleotide identity with both isolates. However, the Australian Bonamia is shown to be more closely related to the New Zealand isolate, suggesting the existence of an oceanic subgroup of Bonamia.
Tipo: Text
Palavras-chave: Small subunit rRNA operon; Flat oyster; Ostrea angasi; Bonamia species.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1981.pdf

Ultrastructure of Mikrocytos mackini, the cause of Denman Island disease in oysters Crassostrea spp. and Ostrea spp. in British Columbia, Canada
Provedor de dados: 5
Autores: Hine, P; Bower, S; Meyer, G; Cochennec, Nathalie; Berthe, Franck.
An ultrastructural study was carried out on Mikrocytos mackini, the cause of Denman Island disease in Pacific oysters Crassostrea gigas in western Canada. Three forms were identified, quiescent cells (QC), vesicular cells (VC) and endosomal cells (EC), QC occurred in the vesicular connective tissue (VCT), haemocytes (hyalinocytes), adductor and heart myocytes, and extracellularly, They had a central round to ovoid nucleus, &lt;7 cisternae of inactive nuclear membrane-bound Golgi, few vesicles and lysosome-like bodies. VC were rarely extracellular and usually occurred in adductor and heart myocytes, in close association with host cell mitochondria. The contents of the host cell mitochondria appeared to pass through a tubular extension into the cytoplasm of...
Tipo: Text
Palavras-chave: Denman Island disease; Amitochondriate protozoan; Ultrastructure; Crassostrea gigas; Mikrocytos mackini.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/2001/publication-815.pdf

Could Mikrocytos roughleyi be a mis-classified haplosporidian?
Provedor de dados: 5
Autores: Cochennec, Nathalie; Le Roux, Frédérique; Berthe, Franck; Hine, Mike.
Bonamiosis refers to diseases of oysters caused by Bonamia ostreae in the Northern Hemisphere and Bonamia sp. in the Southern Hemisphere. Similarly, Mikrocytosis usually refers to diseases of oysters caused by Mikrocytos mackini on the west coast of Canada and Mikrocytos roughleyi on the east coast of Australia.
Tipo: Text
Palavras-chave: Oysters; Diseases; Pathology; Mikrocytos roughleyi.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3286.pdf

Marteiliosis in American oysters Crassostrea virginica reared in France
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Chollet, Bruno.
Progeny of Crassostrea virginica oysters, introduced into France in 1992, were reared at 3 different locations. A survey was taken of these young C, virginica oysters during 1993. Histological and electron microscopical examination revealed a parasite interpreted as a Marteilia-like protozoan in 1 oyster. The structure and the initial stages of the developmental cycle of this parasite are described for the first time in American oysters. However, no mature spores were detected. Thus, exact identification of the protozoan is difficult. This study indicates that American oysters could be infected with Marteilia spp, during cohabitation with Marteilia-infected native bivalves in France.
Tipo: Text
Palavras-chave: American oyster; Crassostrea virginica; Marteiliosis; Marteilia-like parasite.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00258/36926/36177.pdf

Essai d'acclimatation de Crassostrea virginica et performances biologiques comparées avec Crassostrea gigas (1ère partie)
Provedor de dados: 5
Autores: Gerard, Andre; Naciri, Yamama; Peignon, Jean-marie; Ledu, Christophe; Phelipot, Pascal; Baud, Jean-pierre; Nourry, Max; Renault, Tristan; Cochennec, Nathalie.
Premier volet du programme d'essai d'acclimatation de l'huître américaine Crassostrea virginica, ce rapport présente les actions et les résultats de l'année 1992 qui a été consacrée à : • l'importation selon les normes du CIEM d'un lot de 50 huîtres en provenance d'Angleterre, • leur élevage en salle de quarantaine et leur conditionnement en vue d'une accélération de la maturation sexuelle, • l'obtention d'une première génération, ainsi que son suivi en élevage larvaire et en micronurserie à l'URGE-La Tremblade, • au contrôle des performances comparées des deux populations de C. virginica et de C. gigas en nurserie de prégrossissement à l'URRA-Bouin pendant toute la période automnale et hivernale. Au terme de cette première année d'étude il apparait que la...
Tipo: Text
Palavras-chave: Mollusques; Acclimatation; Crassostrea virginica; Crassostrea gigas; Génétique; Pathologie.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00077/18843/16417.pdf

Herpes-like virus infecting Japanese oyster (Crassostrea gigas) spat
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Le Deuff, Rose-marie; Chollet, Bruno.
During the summer of 1993, abnormal sporadic mass mortalities (80-90%) and morbidities occurred among four batches of young Japanese oyster (Crassostrea gigas) spat from the French Atlantic coast. These mortalities were only observed in July. Samples of affected animaIs were examined by electron microscopy. This paper reports the presence and appearance of herpes viruses in these samples.
Tipo: Text
Palavras-chave: Herpes like virus; Mortalities; Crassostrea gigas; Oysters.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-2888.pdf

Compte rendu de la réunion des 14 et 15 Avril 1993 - La Tremblade - Réseau Génétique Mollusques (REGEMO)
Provedor de dados: 5
Autores: Gerard, Andre; Naciri, Yamama; Coatanea, Denis; Martin, Anne-genevieve; Barret, Jean; Claude, Serge; Heurtebise, Serge; Devauchelle, Nicole; Joly, Jean-pierre; Goulletquer, Philippe; Baud, Jean-pierre; Nourry, Max; Bougrier, Serge; Renault, Tristan; Cochennec, Nathalie; Chollet, Bruno; Le Deuff, Rose-marie; Peignon, Jean-marie.
La discussion générale organisée à la fin de la deuxième journée a fait ressortir les points suivants: 1- Les participants se sont déclarés satisfaits de la tenue de la réunion, tant dans son déroulement, que dans les échanges d'informations auxquels elle a donné lieu. La quantité et la qualité des résultats présentés a permis de mettre en évidence la puissance d'analyse que représente le travail en réseau. 2-L'importance de la valorisation des résultats a été soulignée à plusieurs reprises. La diffusion de l'information devrait se faire dans un premier temps par la voie de rapport internes à la DRV, puis par la voie d'articles publiés dans des revues scientifiques. Sur le programme "C. gigas triploïdes", une première diffusion des résultats obtenus en...
Tipo: Text
Palavras-chave: Génétique; Sélection génétique; Huître plate; Ostrea edulis; Génétique population; Croissance.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00049/15981/13423.pdf

Outils de dépistage des pathogènes - Contrat Région Poitou-Charentes 1999 - Convention 99/RPC-A-200 "Pathologie"
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie.
Le Laboratoire de Génétique et Pathologie (LGP) de la station IFREMER de La Tremblade (Charente Maritime) est impliqué aux plans national et international dans l'étude des maladies affectant les mollusques bivalves marins d' intérêt économique et plus particulièrement les huîtres. Des travaux concernant le développement, la validation et l'utilisation d'outils de diagnostic spécifiques d'agents infectieux propres aux coquillages y sont ainsi menés.
Tipo: Text
Palavras-chave: Pathologie; Maladie; Mollusques bivalves; Diagnostic; Huître creuse; Crassostrea gigas.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00043/15471/12850.pdf

Compte-rendu des résultats d'analyses effectuées en histologie - Année 1995
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Chollet, Bruno.
Dans le cadre du Réseau zoosanitaires CEE (huître plate) et suivi d'autres espèces, 890 individus provenant des zones 5, 6 et 7 ont été examinés sur l'ensemble de l'année 1995 par différentes techniques : 472 analyses sous coupes histologiques, 328 analyses sur appositions d'organes, 90 analyses sur milieu au thioglycolate.
Tipo: Text
Palavras-chave: Pathologie; Analyse; Histologie; Technique; Bivalves; Ostrea edulis; Huître plate; Mytilus edulis; Ruditapes philippinarum; Ruditapes decussatus; Cerastoderma edule; Mortalité.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00044/15504/12877.pdf

Etude comparative en cytométrie en flux des fonctions estérases et du métabolisme oxydatif d'hémocytes d'huîtres saines, parasitées, sensibles et résistantes au protozoaire Bonamia ostrea
Provedor de dados: 5
Autores: Cochennec, Nathalie; Garcia, Sandrine; Bedier, Edouard.
In order to fight Bonamiosis, the applicable means are very limited and mostly based on a quick and precocious diagnostic aimed at avoiding the propagation of the disease and a rise in the "resistance" through genetic selection. Various works are conducted in order to understand the oysters' defence mechanisms against this parasite, and then to develop new prophylaxis and fighting methods. In our laboratory, we focus on cellular compartments, the circulating haemocytes, in which B. ostreae multiplies, and their interaction with the parasite.
Tipo: Text
Palavras-chave: Protozoaire; Huître; Hémocytes; Cytométrie en flux; Bonamia ostreae; Biologie cellulaire.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3275.pdf

Epidémiologie de Bonamia ostreae et Marteilia refringens en Bretagne en 1984 et 1985 : situation et évolution
Provedor de dados: 5
Autores: Tige, Gilbert; De Kergariou, Gabriel; Cochennec, Nathalie; Rabouin, Marie-agnès.
A systematic surveillance progam conducted since 1980 along the coasts of Britanny has followed the evolution and epidemiological state of the natural O. eulis oyster beds and seed areas in the intertidal zones and deep water. Presently, Marteilia refringens exists endemically in Brittany estuaries ; the rate and degree of infestation varies from year to year depending on the hydrological conditions and the geographical region. In no case, however, is the return of flat oyster culture envisoned. Bonamia ostreae is present not only in the estuaries but also in the deep-water rearing areas (Baie de Quiberon, Cancale, Baie de St Brieuc). The infestation increases with age, but also depends on the quantity of the stock and the culture practises. In particular,...
Tipo: Text
Palavras-chave: Huître plate; Ostrea edulis; Maladie; Bonamia ostreae; Marteilia refringens; Bretagne; Oyster; Ostrea edulis; Diseases; Bonamia ostreae; Marteilia refringens.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00022/13299/10353.pdf

Experimental transmission of a Herpes-like virus to axenic larvae of Pacific oyster, Crassostrea gigas
Provedor de dados: 5
Autores: Le Deuff, Rose-marie; Nicolas, Jean-louis; Renault, Tristan; Cochennec, Nathalie.
A herpes-like virus which was associated with mortalities amongst hatchery-reared larvae of Pacific oysters, Crassostrea gigas. was observed for the first time in France during the summer 1991 (Nicolas et al.. 1992). Since this first report, we have noted further outbreaks of the disease in the summers of 1992 and 1993 in hatcheries on the western coasts of France in which a similar virus was associated with moribund larvae. Moreover, in the summer 1991, Hine et al. (1992) described a herpes-like virus responsible for larval mortality of hatchery reared C. gigas, in New Zealand. Ail these viruses are c10sely related with respect to their size and morphology and to their apparent cellular tropism for fibroblastic cells.
Tipo: Text
Palavras-chave: Transmission; Herpes like virus; Crassostrea gigas; Oysters.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-2887.pdf

Contrat de Plan Etat Région Poitou-Charentes 1994-1998. Convention 97 RPC R 58 - Programme Pathologie - Rapport Scientifique année 1997
Provedor de dados: 5
Autores: Renault, Tristan; Berthe, Franck; Thebault, Anne; Lipart, Cecile; Chollet, Bruno; Haffner, Philippe; Cochennec, Nathalie.
Le but de ce programme pathologie est de rechercher et d'étudier les agents pathogènes connus et inconnus chez les mollusques bivalves marins, plus particulièrement chez l'huître creuse, Crassostrea gigas, afin d'identifier d'éventuels agents causant des mortalités, de proposer des mesures prophylactiques et de définir des conditions zootechniques permettant aux professionnels de limiter l'impact des maladies sur leur cheptel. La présence de maladies, chez les mollusques bivalves marins dont l'impact socio économique peut être catastrophique pour les productions conchylicoles, et l'accroissement des échanges de produits d'aquaculture entre les pays de la CEE et avec les pays tiers nécessitent le renforcement des recherches dans les domaines de la...
Tipo: Text
Palavras-chave: Pathologie; Pathogènes; Virus; Herpès virus; Crassostrea gigas; Diagnostic; Herpesviridae.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00043/15454/12829.pdf

Compte rendu de la réunion REGEMO sur l'amélioration génétique de l'huître plate du 11 mars 1998 à Nantes : Bilan actualisé du programme de sélection
Provedor de dados: 5
Autores: Goyard, Emmanuel; Lapegue, Sylvie; Cochennec, Nathalie; Baud, Jean-pierre; Langlade, Aime; Joly, Jean-pierre; Buestel, Dominique; Oheix, Jocelyne; Haure, Joel.
Le programme de sélection de l'huître plate a été initié en 1985 par des pathologistes de la Tremblade. La sélection ne portait que sur le seul critère de tolérance des huîtres plates au parasite Bonamia ostreae et correspondait plus à un outil pour étudier divers aspects de la parasitose qu'un un programme d'amélioration génétique visant la relance de la culture de l'huître plate. Dans le cadre du réseau REGEMO, ce programme a ensuite été repris par les généticiens de l'Ifremer : 1) rappel historique et définition d'un vocabulaire commun à l'ensemble des membres du réseau REGEMO. 2) Inventaire et bilan des opération menées ou en cours ( sur la dernière génération de sélection produite ne 1995, sur le matériel issu de cette génération et produit en 1997....
Tipo: Text
Palavras-chave: Génétique; Sélection génétique; Huître plate; Ostrea edulis; Génétique population; Croissance.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00049/15977/13419.pdf

Acclimatation de nouvelles espèces d'huîtres creuses du genre Crassostrea: hybridations et conservatoire de souches. Contrat de Plan Etat Région Poitou- Charentes 1994-1998 - Convention 95/RPC-R-57 "Génétique" - Rapport année 1995
Provedor de dados: 5
Autores: Boudry, Pierre; Naciri, Yamama; Heurtebise, Serge; Delsert, Claude; Ledu, Christophe; Phelipot, Pascal; Chollet, Bruno; Cochennec, Nathalie; Gerard, Andre.
Le laboratoire IFREMER "Génétique Aquaculture et Pathologie" (GAP) (La Tremblade et Bouin) a entrepris des actions de recherche sur ces différents points. L'Unité de Recherche en Génétique, en collaboration avec tous les membres du Réseau Génétique Mollusques (REGEMO), a axé une partie de ses travaux sur l'acclimatation et l'hybridation de différentes espèces du genre Crassostrea. Ces recherches ont débuté avec le soutien du Conseil Général de Charente-Maritime depuis 1992 sur des essais d'acclimatation de C. virginica, l'huître creuse américaine. En prolongement de cette étude, l'URGE a proposé à la région Poitou-Charentes un programme de recherche plus vaste sur l'ensemble des espèces d'huîtres creuses.
Tipo: Text
Palavras-chave: Génétique; Acclimatation; Hybridation; Crassostrea virgnica.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00044/15515/12902.pdf

Marteilia in American oysters Crassostrea virginica reared in France
Provedor de dados: 5
Autores: Renault, Tristan; Cochennec, Nathalie; Chollet, Bruno.
Progeny of Crassostrea virginica oysters, introduced into France in 1992, were reared at 3 different locations. A survey was taken of these young C. virginica oysters during 1993. Histological and electron microscopical examination revealed a parasite interpreted as a Martelia-like protozoan in 1 oyster. The structure and the initial stages of the developmental cycle of this parasite are described for the first time in American oysters. However, no mature spores were detected. Thus, exact identification of the protozoan is difficult. This study indicates that American oysters could be infected with Marteilia spp. during cohabitation with Marteilia-infected native bivalves in France.
Tipo: Text
Palavras-chave: Marteilia like parasite; Marteiliosis; Crassostrea virginica; American oyster.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/publication-2897.pdf

Comparison of Heamograms from resistant and susceptible European flat oysters, Ostrea edulis, exposed to the parasite, Bonamia ostreae
Provedor de dados: 5
Autores: Cochennec, Nathalie; Renault, Tristan; Chollet, Bruno; Maffart, Patricia.
To study the cellular defence mechanisms involved in the resistance of the flat oysters against Bonamia ostreae, a comparaison of haemograms was performed between susceptible and resistant animals
Tipo: Text
Palavras-chave: Pathogen; Bonamia ostreae; Ostrea edulis.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/acte-2906.pdf

Bilans depuis 1999 et évolution de la stratégie du REPAMO
Provedor de dados: 5
Autores: Thebault, Anne; Martin, Anne-genevieve; Pichot, Yves; Chollet, Bruno; Robert, Maeva; Le Coguic, Yvette; Tige, Gilbert; Hirata, Toshio; Mazurie, Joseph; Le Saux, Jean-claude; Masson, Nadine; Auby, Isabelle; Maurer, Daniele; Le Roux, Frédérique; Cochennec, Nathalie; Renault, Tristan; Berthe, Franck; Grizel, Henri.
The main objectives of the Mollusc Pathology Network (REPAMO) are to prevent introductions or outbreaks of infectious agents, prevent spread within a farm and especially from one farm to another, to study ways of decreasing the impact of infectious agent and to monitor the development of these pathogens in order to guarantee the health status of oysters exchanged with our commercial partners. On the whole, REPAMO's activities have not changed and include: - monitoring the development of diseases that have to be reported to authorities and carrying out analyses to classify zones: bonamiosis and marteiliosis; - baseline monitoring of farmed and wild populations of bivalve molluscs; - studying cases of abnormal mortality events; - controlling mollusc...
Tipo: Text
Palavras-chave: Mollusques; Réseau surveillance; Pathologie; REPAMO.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3265.pdf

Haplosporidiosis in the pacific oyster Crassostrea gigas from the French Atlantic coast
Provedor de dados: 5
Autores: Renault, Tristan; Stokes, Nancy; Chollet, Bruno; Cochennec, Nathalie; Berthe, Franck; Gerard, Andre; Burreson, Eugene.
Two cases of haplosporidian infection occurred during 1993 in Pacific oysters Crassostrea gigas from the French Atlantic coast. The localization and ultrastructure of the plasmodia are described. In situ hybridization of infected tissue sections was conducted with DNA probes for oyster-infecting haplosporidians. The Haplosporidium nelsoni-specific DNA probe MSX1347 hybridized with the C. gigas parasite, and the H, costale-specific probe SSO1318 did not hybridize. Total genomic DNA was extracted from the infected tissue sections for polymerase chain reaction (PCR) amplification of the haplosporidian. PCR amplifications with H. nelsoni-specific primers and with 'universal' actin primers did not yield the expected products of 573 and 700 bp, respectively. A...
Tipo: Text
Palavras-chave: Haplosporidium nelsoni; Haplosporidiosis; Crassostrea gigas; Pacific oyster.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-821.pdf

L'amélioration des performances de l'huître plate européenne Ostrea edulis par la sélection génétique
Provedor de dados: 5
Autores: Bedier, Edouard; Baud, Jean-pierre; Cochennec, Nathalie; Cornette, Florence; Gerard, Andre; Goyard, Emmanuel; Joly, Jean-pierre; Kopp, Joel; Langlade, Aime; Le Coguic, Yvette; Mazurie, Joseph; Nourry, Max.
The European flat oyster Ostrea edulis has been considered as the traditional French oyster for a very long time and has now nearly disappeared from our farms, as a consequence of the two successive epizootic of the Marteilia refringens parasite and Bonamia ostreae. The actual quasi monoculture of Crassostrea gigas has made necessary the search for a diversification in oyster culture, including the search for a new start of the indigenous flat oyster culture. The Ifremer has been conducting parallel works since 1985 in order to better understand the biology of the parasite as well as to try and select different lines of flat oyster resistant to Bonamia ostreae.
Tipo: Text
Palavras-chave: Bonamia ostrea; Huître plate; Sélection Génétique; Ostrea edulis.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/acte-3274.pdf