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Registros recuperados: 73 | |
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Aguirre Guzman, G; Ascencio, F; Saulnier, Denis. |
The pathogenicity of Vibrio penaeicida Strains KH-1 and AM101, their culture-free supernatant (CFS), and their protein fraction obtained by 40% of ammonium sulfate precipitation (PFs40) were assessed in experimental challenges against juvenile Litopenaeus vannamei. Live Vibrio cells, CFS, and PFs40 from the AM101 strain produced a significantly higher mortality (p < 0.05) compared to the KH-1 strain. Toxicity and median lethal doses (LD50) of Fast Protein Liquid Chromatography (FPLC) products were evaluated on L. vannamei. The first FPLC fraction sample (A) from PFs40 of the AM101 strain displayed LD50 values of 1.68 and 5.61 mu g protein ind.(-1), respectively. The second FPLC process from Fraction A showed a peak (A1) also with toxic effects to... |
Tipo: Text |
Palavras-chave: Pathogenicity; Exotoxin; Shrimp; Litopenaeus vannamei; Cysteine protease; Vibrio penaeicida. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-3618.pdf |
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Aguirre-guzman, Gabriel; Labreuche, Yannick; Ansquer, Dominique; Espiau, Benoit; Levy, Peva; Ascencio, Felipe; Saulnier, Denis. |
The pathogenicity of two V. penaeicida strains, AM101 and KH-1, with different geographic origin, and V. nigripulchritudo strain AM102, were investigated in juvenile blue shrimp species Litopenaeus stylirostris. Alive bacteria and protein fractions (PFs) obtained from cell-free supernatants (CFS) were used in experimental challenges. Strains AM102, AM101, and KH-1 produced respectively 60, 54 and 12% mortality at 96h after infection using 104 cfu mL-1 of bacterial suspension. Exocellular toxin-like factors were evidenced in CFS from the New Caledonian strains (AM102 and AM101) but not the Japanese strain (KH-1). At 48h post injection of each CFS, mortality rates were respectively 96,98 and 5% when these strains were cultivated at 20°C, whereas only O,16... |
Tipo: Text |
Palavras-chave: Pathogenicity; Exotoxin; Shrimp; Litopenaeus stylirostris; Vibrio nigripulchritudo; Vibrio penaeicida. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-2807.pdf |
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Alix, Maud; Gasset, Eric; Bardon-albaret, Agnes; Noel, Jean; Pirot, Nelly; Perez, Valérie; Coves, Denis; Saulnier, Denis; Lignot, Jehan-hervé; Cucchi, Patricia N.. |
Background Ephippidae fish are characterized by a discoid shape with a very small visceral cavity. Among them Platax orbicularis has a high economic potential due to its flesh quality and flesh to carcass ratio. Nonetheless, the development of its aquaculture is limited by high mortality rates, especially due to Tenacibaculum maritimum infection, occurring one to three weeks after the transfer of fishes from bio-secure land-based aquaculture system to the lagoon cages for growth. Among the lines of defense against this microbial infection, the gastrointestinal tract (GIT) is less studied. The knowledge about the morphofunctional anatomy of this organ in P. orbicularis is still scarce. Therefore, the aims of this study are to characterize the GIT in... |
Tipo: Text |
Palavras-chave: Digestive system; Tenacibaculosis; Mucous; Osmoregulation; Absorption; Batfish; Teleost. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00652/76421/77485.pdf |
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Arnaud, Sophie; Goyard, Emmanuel; Vonau, Vincent; Herbaut, C; Prou, Jean; Saulnier, Denis. |
Most bivalves species of the genus Pinctada are well known throughout the world for production of white or black pearls of high commercial value. For cultured pearl production, a mantle allograft from a donor is implanted into the gonad of a recipient oyster, together with a small inorganic bead. Because of the dedifferentiation of cells during the first steps of the host oyster's immunological reaction, so far the fate of the graft and its exact role in the process of pearl formation could not be determined via classical histological methods. Here we report the first molecular evidence of the resilience of the graft in the recipient organism by showing that cells containing genome from the donor are still present at the end of pearl formation. These... |
Tipo: Text |
Palavras-chave: Genotype; Pearl; Pearl sac; Grafting; Biomineralization; Pearl oyster. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2456.pdf |
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Bardon-albaret, Agnes; Gasset, Eric; Teissier, Alexandre; Teiri, W; Maamaatuaiahutapu, M; David, R; Tayale, Alexandre; Belliard, Corinne; Levy, Peva; Basset, Caline; Sicard, Julien; Magre, Kevin; Herne, Antoine; Reverter, Myriam; Sasal, Pierre; Coves, Denis; Saulnier, Denis. |
Tipo: Text |
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Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00281/39246/37819.pdf |
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Binesse, J; Delsert, Claude; Saulnier, Denis; Champomier Verges, M; Zagorec, M; Munier Lehmann, H; Mazel, D; Le Roux, F. |
Genomic data combined with reverse genetic approaches have contributed to the characterization of major virulence factors of Vibrio species; however, these studies have targeted primarily human pathogens. Here, we investigate virulence factors in the oyster pathogen Vibrio splendidus LGP32 and show that toxicity is correlated to the presence of a metalloprotease and its corresponding vsm gene. Comparative genomics showed that an avirulent strain closely related to LGP32 lacked the metalloprotease. The toxicity of LGP32 metalloprotease was confirmed by exposing mollusk and mouse fibroblastic cell lines to extracellular products (ECPs) of the wild type (wt) and a vsm deletion mutant (Delta vsm mutant). The ECPs of the wt induced a strong cytopathic effect... |
Tipo: Text |
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Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4931.pdf |
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Bridel, Sébastien; Bourgeon, Frédéric; Marie, Arnaud; Saulnier, Denis; Pasek, Sophie; Nicolas, Pierre; Bernardet, Jean-françois; Duchaud, Eric. |
Tenacibaculum maritimum is responsible for tenacibaculosis, a devastating marine fish disease. This filamentous bacterium displays a very broad host range and a worldwide geographical distribution. We analyzed and compared the genomes of 25 T. maritimum strains, including 22 newly draft-sequenced genomes from isolates selected based on available MLST data, geographical origin and host fish. The genome size (~3.356 Mb in average) of all strains is very similar. The core genome is composed of 2116 protein-coding genes accounting for ~75% of the genes in each genome. These conserved regions harbor a moderate level of nucleotide diversity (~0.0071 bp−1) whose analysis reveals an important contribution of recombination (r/m ≥ 7) in the evolutionary process of... |
Tipo: Text |
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Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00630/74174/73747.pdf |
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Brizard, Raphael; Boudry, Pierre; Haffray, Patrick; Labbe, C.; Suquet, Marc; Robert, Rene; Masse, G.; Pepin, Jean-francois; Saulnier, Denis. |
In order to improve oyster culture, many research programs try and propose new methods aiming at improving genetically the product performances and quality (selection, polyploidisation). As for terrestrial animal production, the continuity of the different works as well as the spreading of the genetical progress would be made easier by the development of conservation techniques of the selected genotypes. Cryopreservation, which is often used in selection programs of terrestrial animals or fish farming species, is not always available for bivalves. This technique would enable the conservation of the gametes of individuals selected for their high growth potential, their resistance to diseases and/or their quality for a smaller cost and less risks than the... |
Tipo: Text |
Palavras-chave: Tetraploïde; Diploïde; Concervation; Spermatozoides; Cryoconservation; Génétique; Crassostrea gigas; Huîtres. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-3339.pdf |
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Cardona, Emilie; Gueguen, Yannick; Magré, Kevin; Lorgeoux, Bénédicte; Piquemal, David; Pierrat, Fabien; Noguier, Florian; Saulnier, Denis. |
Background Biofloc technology (BFT), a rearing method with little or no water exchange, is gaining popularity in aquaculture. In the water column, such systems develop conglomerates of microbes, algae and protozoa, together with detritus and dead organic particles. The intensive microbial community presents in these systems can be used as a pond water quality treatment system, and the microbial protein can serve as a feed additive. The current problem with BFT is the difficulty of controlling its bacterial community composition for both optimal water quality and optimal shrimp health. The main objective of the present study was to investigate microbial diversity of samples obtained from different culture environments (Biofloc technology and clear... |
Tipo: Text |
Palavras-chave: Shrimp; Biofloc; Clear sea water; Bacterial communities; Culture environment; Microbiota. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00346/45694/45314.pdf |
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Cardona, Emilie; Saulnier, Denis; Lorgeoux, Benedicte; Chim, Liet; Gueguen, Yannick. |
This study compares the antioxidant and antimicrobial transcriptional expression of blue shrimps reared according to two different systems, BioFloc Technology (BFT) and Clear sea Water (CW) and their differential responses when facing an experimental sublethal hydrogen peroxide stress. After 30 days of rearing, juvenile shrimps were exposed to H2O2 stress at a concentration of 30 ppm during 6 hours. The oxidative stress caused by H2O2 was examined in the digestive glands of the shrimp, in which antioxidant enzyme (AOE) and antimicrobial peptide (AMP) gene expression were analysed by quantitative real-time PCR. Results showed that rearing conditions did not affect the expression of genes encoding AOEs or AMPs. However, H2O2 stress induced a differential... |
Tipo: Text |
Palavras-chave: Biofloc; Shrimps; Antimicrobial peptides; Antioxidant enzymes. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00270/38116/36269.pdf |
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Chim, Liet; Cardona, Emilie; Lorgeoux, Benedicte; Gueguen, Yannick; Saulnier, Denis; Goguenheim, Jean; Wantiez, Laurent; Cahu, Chantal. |
Shrimp farming in New-Caledonia faces up to difficulties. A fluctuating quality of broodstock prevents sustainable production of larvae in quantity and quality. The traditional extensive rearing method of broodstock in outdoor earthen ponds used in New Caledonia raises several issues: poor water quality control and biosecurity. Therefore it is fundamental to modify the broodstock culture strategy in order to achieve an easier water quality management and maximal biosecurity. Biofloc technology (BFT) offers easier water quality management, higher natural productivity, higher level of biosecurity, and could be a good alternative. Since 2011 a R&D program started under the supervision of IFREMER in New Caledonia and French Polynesia in order to study and... |
Tipo: Text |
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Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00250/36084/34635.pdf |
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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 |
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Cochennec-laureau, Nathalie; Levy, Peva; Saulnier, Denis; Fougerouse, Angelique. |
L’importance socio-économique de l’activité perlière justifie que le Service de la Perliculture mette en place un réseau de surveillance pathologique de l’huître perlière Pinctada margaritifera en Polynésie française. Les objectifs de ce réseau sont de prévenir l’introduction ou l’apparition d’agents infectieux, de prévenir leur propagation à l’intérieur d’une zone d’élevage, d’étudier les moyens de limiter leur impact, de surveiller leur évolution et enfin de garantir les échanges entre les zones d’élevage. Cette première année a permis d’élaborer le schéma de fonctionnement du réseau et de vérifier sa faisabilité. Cinq zones de prélèvements ont été définies en fonction de critères d’accessibilité à la zone et de facilité d’acheminement des échantillons,... |
Tipo: Text |
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Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00168/27886/26141.pdf |
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Cochennec-laureau, Nathalie; Montagnani, Caroline; Saulnier, Denis; Fougerouse, Angelique; Levy, Peva; Lo, Cedrik. |
Pearl oyster grafting is a complex surgical operation that should lead to pearl formation after approximately eighteen months. Although this technique has been used for many years in French Polynesia, the grafting process is still not standardised. While studies have been carried out in order to improve graft performance and yield, these remain highly variable due to post-grafting mortality, nucleus rejection and unreliable pearl quality, all of which constrain pearl farm profitability. The present study uses histological analysis to monitor oysters that either rejected or retained their nuclei. Both groups of oysters are compared in terms of evolution of the graft, which could influence retention, and the development of a pearl sac in cases where grafting... |
Tipo: Text |
Palavras-chave: Grafting process; Pearl formation; Pearl oyster; Pteriidae; Pinctada margaritifera. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00002/11288/7823.pdf |
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De Decker, Sophie; Normand, Julien; Duperthuy, Marylise; Boudry, Pierre; Saulnier, Denis. |
Rearing of Crassostrea gigas is the most economically important aquaculture activity in France. Bacteria belonging to Vibrio genus constitute one of the most abundant bacterial group in marine ecosystems. Two Vibrio species, V. splendidus and V. aestuarianus, were associated with many cases of mortality events in reared C. gigas spat and juvenile oysters, commonly during summer. This summer mortality syndrome has been extensively documented as the result of complex interactions between pathogens, host and environmental conditions. This work aims to study the Vibrio-host interactions and their modulations according to the virulence of pathogens and the genetic and/or physiological parameters of the host. These factors will be characterized by in vitro and... |
Tipo: Text |
Palavras-chave: Genetic; Pathogens; Interaction; Vibrio; Crassostrea gigas; Oyster. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/acte-3430.pdf |
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De Decker, Sophie; Normand, Julien; Saulnier, Denis; Pernet, Fabrice; Castagnet, Sophie; Boudry, Pierre. |
Several Vibrio species are known to be pathogenic to the Pacific oyster Crassostrea gigas. Survival varies according to pathogen exposure and high mortality events usually occur in summer during gametogenesis. In order to study the effects of gametogenetic status and ploidy (a factor known to affect reproduction allocation in oysters) on vibriosis survival, we conducted two successive experiments. Our results demonstrate that a common bath challenge with pathogenic Vibrio splendidus and Vibrio aestuarianus on a mixture of mature, spawning and non-mature oysters can lead to significant mortality. Previous bath challenges, which were done using only non-mature oysters, had not produced mortality. Immunohisto-chemical analyses showed the affinity of Vibrio... |
Tipo: Text |
Palavras-chave: Experimental vibriosis; Crassostrea gigas; Vibrio; Survival distribution function; Triploidy; Reproductive effort. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00030/14108/11368.pdf |
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De Decker, Sophie; Reynaud, Yann; Saulnier, Denis. |
The aim of that studywas to explore the hypothesis that a quorumsensingmechanismmodulatesmetalloprotease gene expression of two Vibrio species pathogenic for oyster, at intraspecific (Vibrio splendidus) and interspecific (V. splendidus affecting V. aestuarianus) levels. Metalloprotease activities (Vsm for V. splendidus LGP32 and Vam for V. aestuarianus 02/041) and growth curves obtained by real-time PCR assay revealed cell density-dependent metalloprotease inductions triggered between 12 h and 16 h of culture. A quorum sensing assay was then developed using a conditioned medium prepared from supernatant of a mutant strain of V. splendidus LGP32 unable to produce metalloprotease. Specific real-time qPCR assays targeting metalloprotease genes vsm and vam... |
Tipo: Text |
Palavras-chave: Quorum sensing; Crassostrea gigas; Vibrio; Metalloprotease; Gene expression. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00124/23539/21381.pdf |
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De Decker, Sophie; Saulnier, Denis. |
The understanding of reciprocal interactions between Crassostrea gigas and Vibrio sp., whether these be virulent or avirulent, is vital for the development of methods to improve the health status of cultured oysters. We describe an original non-invasive experimental infection technique using cohabitation, designed to explore these interactions. Using real-time PCR techniques we examined the dynamics of virulent and avirulent Vibrio sp. in oyster hemolymph and tank seawater, and made a parallel study of the expression of four genes involved in oyster immune defense: Cg-BPI, Cg-EcSOD, Cg-IκB, Cg-TIMP. No mortality occurred in control animals, but oysters put in cohabitation for 2–48 h with animals previously infected by two Vibrio pathogens suffered... |
Tipo: Text |
Palavras-chave: Oyster-Vibrio interactions; Pathogenesis; Immune response; Non-invasive experimental challenge; Real-time PCR. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00025/13604/10681.pdf |
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Registros recuperados: 73 | |
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