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| Registros recuperados: 57 | |
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| 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 |
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| 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 μm 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 |
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| 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 |
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| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/publication-2765.pdf |
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| 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 & Tigé, 1982), and in the European countries including the UK, Holland, lreland and Spain (Bannister & 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 |
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| 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 |
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| 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 |
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| 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 |
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| 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 |
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| 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 |
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| 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 |
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| 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 |
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| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00408/51953/52588.pdf |
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| 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 |
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| 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 |
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| 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 |
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| 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 |
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| 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 |
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| 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, <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 |
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| Registros recuperados: 57 | |
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