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Registros recuperados: 140 | |
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Bouilly, Karine; Leitao, Alexandra; Mccombie, Helen; Chaves, R.; Guedes Pinto, H; Boudry, Pierre; Lapegue, Sylvie. |
In the Pacific oyster, Crassostrea gigas hypodiploid aneuploid cells with 2n=19, 18 or 17 chromosomes have regularly been reported. There is a negative correlation between somatic aneuploidy and growth rate in oysters (Leitão et al., 2001a) as well as evidence for a genetic basis (Leitão et al., 2001b). Furthermore, non-random chromosome loss has been demonstrated in aneuploid karyotypes of C. gigas using the G-banding technique (Leitão et al., 2001c). This poster summarises different studies used to investigate the effects of the herbicide atrazine on the level of aneuploidy in this species |
Tipo: Text |
Palavras-chave: Genetic; Aneuploidy; Toxicology; Impact; Atrazine; Crassostrea gigas; Pacific oysters. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-3489.pdf |
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Sussarellu, Rossana; Huvet, Arnaud; Lapegue, Sylvie; Quillen, Virgile; Lelong, Christophe; Cornette, Florence; Jensen, Lasse Fast; Bierne, Nicolas; Boudry, Pierre. |
Background Originating from Northeast Asia, the Pacific oyster Crassostrea gigas has been introduced into a large number of countries for aquaculture purpose. Following introduction, the Pacific oyster has turned into an invasive species in an increasing number of coastal areas, notably recently in Northern Europe. Methods To explore potential adaptation of reproductive traits in populations with different histories, we set up a common garden experiment based on the comparison of progenies from two populations of Pacific oyster sampled in France and Denmark and their hybrids. Sex ratio, condition index and microarray gene expression in gonads, were analyzed in each progeny (n = 60). Results A female-biased sex-ratio and a higher condition index were... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Adaptation; Invasiveness; Fertility; Sex-ratio; Transcriptome; Microarray. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00287/39829/38343.pdf |
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Boudry, Pierre; Huvet, Arnaud; Fabioux, Caroline; Lapegue, Sylvie; Heurtebise, Serge; Ledu, Christophe; Blouin, Frederic; Phelipot, Pascal; Gerard, Andre. |
L'étude de la variabilité génétique de l' huître creuse Crassastrea gigas est un point essentiel dans la mise en place de programmes de gestion des ressources génétiques et de sélection chez cette espèce. C. gigas, originaire du Japon, a été introduite dans de nombreuses régions du monde et représente aujourd'hui plus de 95 % de la production mondiale d' huîtres. Introduite en France au début des années 1970 pour remplacer l' huître portugaise Crassostrea angulata, c'est aujourd 'hui une ressource de première importance pour notre région. Malgré la maîtrise du cycle de reproduction de l'espèce et son importance commerciale, elle n' a pas été génétiquement améliorée et on peut donc considérer les stocks comme « sauvages» ou « non domestiqués ». De plus, la... |
Tipo: Text |
Palavras-chave: Génétique; Ressources génétiques; Différenciation génétique; Hybridation; Anomalies chromosomiques; Huîtres creuses; Crassostrea gigas; Crassostrea angulata. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00044/15564/12955.pdf |
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Lallias, Delphine; Arzul, Isabelle; Heurtebise, Serge; Ferrand, Sylvie; Chollet, Bruno; Robert, Maeva; Beaumon, Andy; Boudry, Pierre; Morga, Benjamin; Lapegue, Sylvie. |
Bonamiosis is a parasitic disease (causative agent: Bonamia ostreae) affecting the European flat oyster Ostrea edulis, responsible for a drastic decline in its aquaculture production. Selective breeding programs for resistance to bonamiosis have been undertaken to counter this disease. In the present study, a 6-month cohabitation challenge experiment was performed in order to transmit the disease from wild oysters injected with the parasite to two tested families of oysters (20 and 8-month old at the beginning of the experiment, with different genetic backgrounds) originating from a selective breeding program developed by IFREMER in France. Mortalities were checked daily and ventricular heart smears were performed on dying or moribund oysters to detect the... |
Tipo: Text |
Palavras-chave: Heart smear; Transmission; Cohabitation experiment; Bonamia ostreae; Ostrea edulis. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4783.pdf |
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Rohfritsch, Audrey; Bierne, Nicolas; Boudry, Pierre; Heurtebise, Serge; Lapegue, Sylvie. |
Originating from the north eastern Asia, Crassostrea gigas has been introduced and translocated, mainly for aquaculture purpose, into several European countries (from Norway to Portugal and in the Mediterranean Sea) (1). Although highly variable, the invasiveness pattern of C. gigas has been demonstrated in several countries and therefore considered as a pest or a noxious species in those areas (2 and 3).Our project aims at identifying the characteristics of such a flourishing species: can its success be explained by chance and/or global warming only or does it exhibit a more important potential of adaptation than other species? Therefore we developed a population genomics approach, known as "genome scan". It corresponds to the study of numerous loci... |
Tipo: Text |
Palavras-chave: Invasive; AFLP; Genome scan; Crassotrea gigas; Pacific oyster. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/acte-4805.pdf |
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Lallias, Delphine; Gomez-raya, L.; Haley, C. S.; Arzul, Isabelle; Heurtebise, Serge; Beaumont, A. R.; Boudry, Pierre; Lapegue, Sylvie. |
We have identified quantitative trait loci (QTL) in the flat oyster (Ostrea edulis) for resistance to Bonamia ostreae, a parasite responsible for the dramatic reduction in the aquaculture of this species. An F-2 family from a cross between a wild oyster and an individual from a family selected for resistance to bonamiosis was cultured with wild oysters injected with the parasite, leading to 20% cumulative mortality. Selective genotyping of 92 out of a total of 550 F-2 progeny (i.e., 46 heavily infected oysters that died and 46 parasite-free oysters that survived) was performed using 20 microsatellites and 34 amplification fragment length polymorphism primer pairs. Both a two-stage testing strategy and QTL interval mapping methods were used. The two-stage... |
Tipo: Text |
Palavras-chave: Statistical power; Survival analysis; QTL mapping; Disease resistance; Ostrea edulis. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6682.pdf |
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Flahauw, Emilie; Davenel, Armel; Quellec, Stéphane; Quillien, Virgile; Degremont, Lionel; Lapegue, Sylvie; Hatt, Philippe-jacques. |
Biological parameters of the cupped oyster Crassostrea gigas such as growth, reproductive effort (duration of the gametogenesis, date of spawning, and fecundity) differ widely among oysters in the same location. Furthermore, most of the traditional methods, like histological observations, could lead to large variability on the observations and the measurements ofthese traits, and large uncertainties on their changes over time. These can be drastically reduced by using Magnetic Resonance Imaging (MRI) which is a non invasive method allowing to measure the same individual during its development. Forty oysters were assessed using MRI for the volume of whole soft body, the intra valves space, the adductor muscle, and the gonad, which also include the digestive... |
Tipo: Text |
Palavras-chave: Molluscs; Crassostrea gigas; Gonad; Histology; MRI. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00107/21784/19370.pdf |
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Bouilly, Karine; Bonnard, Marc; Grouhel, Stephanie; Lapegue, Sylvie. |
Divers travaux menés depuis 1984 montrent qu’il existe, chez l’huître creuse Crassostrea gigas, des cellules présentant un nombre anormal de chromosomes (2n = 19, 18 ou même 17 au lieu de 2n = 20). Or, une corrélation négative entre l’aneuploïdie somatique et le taux de croissance a été décrite à de nombreuses reprises (Thiriot-Quiévreux et al., 1988, 1992 ; Leitão et al., 2001a ; Zouros et al., 1996). Bien que les causes environnementale et /ou génétique de l’aneuploïdie restent encore largement inconnues, des études récentes ont permis de poser l’hypothèse d’une base génétique large dans la détermination de ce caractère (Leitão et al., 2001b). De plus, un effet toxique direct de l’atrazine (herbicide couramment utilisé dans la région) sur le génome d’une... |
Tipo: Text |
Palavras-chave: Génétique; Chromosomes; Aneuploïdie; Huîtres creuses; Crassostrea gigas. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00044/15476/12855.pdf |
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Morvezen, Romain; Cornette, Florence; Charrier, Gregory; Guinand, Bruno; Lapegue, Sylvie; Boudry, Pierre; Laroche, Jean. |
We report the isolation, development and multiplex optimisation of 12 new microsatellite loci for the great scallop, Pecten maximus. Diversity was moderate to high, with number of alleles ranging from 4 to 20 and observed heterozygosity between 0.28 and 0.88. Progeny produced in a commercial hatchery was used to test locus power for parentage assignment. The percentage of offspring that was unambiguously assigned to a unique pair of parents was 97% (software package CERVUS-COLONY). Parentage assignment revealed that 22% of the studied progeny resulted from unplanned crosses. Effective population size of the study progeny was also estimated. Our study illustrates the power of microsatellites for the genetic monitoring of hatchery-produced great scallops. |
Tipo: Text |
Palavras-chave: Microsatellites; Polymerase chain reaction; Parentage; Assignment; Bivalve mollusc. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00137/24822/22907.pdf |
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Danic-tchaleu, Gwenaelle; Heurtebise, Serge; Morga, Benjamin; Lapegue, Sylvie. |
Background Because of its typical architecture, inheritance and small size, mitochondrial (mt) DNA is widely used for phylogenetic studies. Gene order is generally conserved in most taxa although some groups show considerable variation. This is particularly true in the phylum Mollusca, especially in the Bivalvia. During the last few years, there have been significant increases in the number of complete mitochondrial sequences available. For bivalves, 35 complete mitochondrial genomes are now available in GenBank, a number that has more than doubled in the last three years, representing 6 families and 23 genera. In the current study, we determined the complete mtDNA sequence of Ostrea edulis, the European flat oyster. We present an analysis of features of... |
Tipo: Text |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00045/15628/13031.pdf |
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Bouilly, Karine; Gagnaire, Beatrice; Bonnard, Marc; Thomas-guyon, Helene; Renault, Tristan; Miramand, Pierre; Lapegue, Sylvie. |
Pacific oysters, Crassostrea gigas, are commonly reared in estuaries where they are exposed to anthropogenic pollution. Much research has been made on the toxicity of cadmium to aquatic organisms because the compound recurrently contaminates their environment. Our study examined the influence of cadmium on aneuploidy level (lowered chromosome number in a percentage of somatic cells) and hemocyte parameters in C. gigas at different stages of life. Adults and juveniles were exposed to two different concentrations of cadmium. The first concentration applied was equivalent to a peak value found in Marennes-Oleron bay (Charente-Maritime, France; 50 ng L-1) and the second was 10 times higher (500 ng L-1). Exposure to 50 ng L-1 cadmium caused a significant... |
Tipo: Text |
Palavras-chave: Phenoloxidase; Flow cytometry; Hemocytes; Aneuploidy; Crassostrea gigas; Cadmium. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1687.pdf |
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Lallias, Delphine; Beaumont, Andy; Haley, Chris; Heurtebise, Serge; Boudry, Pierre; Lapegue, Sylvie. |
A breeding programme has been undertaken by Ifremer to produce selected Ostrea edulis families which are resistant to Bonamia ostreae, a parasite which is the most significant constraint on aquaculture of this oyster. Using such families, we aimed to identify Quantitative Trait Loci (QTLs) of resistance/susceptibility to bonamiosis. We used an F2 family derived from a bi-parental cross between a wild oyster and an individual from one of the selected oyster families. A total of 550 F2 individuals from the family cohabited with wild oysters that were injected with the parasite. Mortality was checked daily over six months and heart smears were used on moribund or dying oysters to detect the presence and level of infection of the parasite. Ninety two F2... |
Tipo: Text |
Palavras-chave: QTLs; Flat oyster; Ostrea edulis; Bonamia ostreae; Genetic; QTL. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/acte-3726.pdf |
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Lapegue, Sylvie; Taris, Nicolas; Lallias, Delphine; Bonhomme, Francois; Boudry, Pierre. |
The European flat oyster (Ostrea edulis L.) is a marine bivalve whose natural geographical distribution ranges along the European Atlantic coast from Norway to Morocco, in addition to the Mediterranean and Black Sea. The latest results obtained on the genetic differentiation between these populations have led us to persue studies at a finer scale, in order to estimate the effective number of breeders and the temporal dynamics of reproduction and, more specially, recruitment. Several experiments were performed to document (1) the variance in allele frequencies during a natural settlement period, (2) the paternal contribution to fertilization by analyzing larvae sampled at the brooding stage within individual females, (3) the variance of individual... |
Tipo: Text |
Palavras-chave: Recruitment; Microsatellite markers; Ostrea edulis; European flat oyster; Genetic. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-3485.pdf |
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Lallias, Delphine; Boudry, Pierre; Batista, Frederico; Beaumont, Andy; King, Jonathan W.; Turner, John R.; Lapegue, Sylvie. |
The Pacific oyster, Crassostrea gigas, native to northeast Asia, is one of the most important cultured shellfish species. In Europe, Pacific oysters first settled along the Atlantic coasts of France at the end of the 1960s but rapidly spread and are now widely established. Twenty-two sites in the United Kingdom (UK), Ireland, Denmark, France and Spain were sampled to assess genetic diversity and differentiation. Hatchery-propagated stocks from two hatcheries located in the UK also were included. Two main genetic clusters were identified from pairwise genetic differentiation indexes, Bayesian clustering methods or neighbour-joining analysis, based on 7 microsatellite loci: (1) a Northeast cluster (including feral samples from East England, Ireland and... |
Tipo: Text |
Palavras-chave: Invasion genetics; Marine mollusc; Microsatellites; MtDNA; Pacific oyster; Crassostrea gigas. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00268/37973/36052.pdf |
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Lallias, Delphine; Lapegue, Sylvie; Harley, Crhis; Boudry, Pierre; Heurtebise, Serge; Beaumont, Andy. |
The flat oyster Ostrea edulis is the species endemic to European coasts, both Atlantic and Mediterranean. It has been exploited since Roman times, but its aquaculture production decreased from around 20000 tons in the 1950's to 1500 tons today because of two successive diseases due to the intracellular parasites Marteilia refringens and Bonamia ostreae. Since 1985, Ifremer has been undertaking a breeding program to produce families of oysters tolerant to Bonamia. In this context, a further step would be to identify QTLs for resistance to this parasite. Therefore, as a first step a genetic map is now being built. The establishment of a genetic linkage map will provide a foundation for the mapping of QTLs, with the ultimate objective to implement... |
Tipo: Text |
Palavras-chave: QTLs; Ostrea edulis; Flat oyster; Genetic linkage map; Genetic. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-3466.pdf |
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Rohfritsch, Audrey; Bierne, Nicolas; Boudry, Pierre; Heurtebise, Serge; Cornette, Florence; Lapegue, Sylvie. |
Crassostrea gigas originated from the Pacific coast of Asia, but was introduced into several European countries in the early 1970s. Natural populations have now spread across the length of the western seaboard of Europe. To elucidate the demographic and selective processes at play during this rapid expansion, genome-scan analysis was performed on different populations. High diversities and low differentiation were observed overall, but significant genetic differentiation was found among newly established populations and between the newly established northern group and a nearly panmictic group composed of southern European populations and a population from Japan. Loss of genetic diversity was also seen in the north, likely caused by founder events during... |
Tipo: Text |
Palavras-chave: AFLPs; Crassostrea gigas; Genome scan; Invasive species; Microsatellites; SNPs. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00149/25977/24070.pdf |
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Harrang, Estelle; Lapegue, Sylvie; Morga, Benjamin; Bierne, Nicolas. |
Marine bivalves show among the greatest allozyme diversity ever reported in Eukaryotes, putting them historically at the heart of the neutralist-selectionist controversy on the maintenance of genetic variation. Although it is now acknowledged that this high diversity is most probably a simple consequence of a large population size, convincing support for this explanation would require a rigorous assessment of the silent nucleotide diversity in natural populations of marine bivalves, which has not yet been done. This study investigated DNA sequence polymorphism in a set of 37 nuclear loci in wild samples of the flat oyster Ostrea edulis. Silent diversity was found to be only moderate (0.7%), and there was no departure from demographic equilibrium under the... |
Tipo: Text |
Palavras-chave: Nucleotide; Polymorphism; Marine bivalve; Deleterious; Mutations; Genetic load; Ostrea edulis. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00125/23610/21444.pdf |
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Registros recuperados: 140 | |
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