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Registros recuperados: 273
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Characterization of 27 microsatellite loci in the European flat oyster Ostrea edulis ArchiMer
Lallias, Delphine; Stockdale, Ruth; Boudry, Pierre; Beaumont, Andy R.; Lapegue, Sylvie.
The flat oyster Ostrea edulis is native to Europe and populations have been severely depleted by the parasite Bonamia ostreae since the 1980s. Additional genetic markers are required to improve population genetics study and linkage map development for selection for B. ostrea-resistance in this species. Here, we characterized 27 novel microsatellite loci for O. edulis. Number of alleles per locus ranged from 6 to 25 and observed heterozygosity between 0.375 and 1. Null alleles were suggested at a few loci but most loci were in Hardy-Weinberg agreement enabling their reliable use in further population and mapping genetics approaches.
Tipo: Text Palavras-chave: Universal tailed primer labelling; Oysters; Ostrea edulis; Microsatellites.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/2009/publication-6421.pdf
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Characterization of GnRH-related peptides from the Pacific oyster Crassostrea gigas ArchiMer
Bigot, Laetitia; Zatylny-gaudin, Celine; Rodet, Franck; Bernay, Benoit; Boudry, Pierre; Favrel, Pascal.
Gonadotropin-releasing hormone (GnRH), a key neuropeptide regulating reproduction in vertebrates has now been characterized in a number of non-vertebrate species. Despite the demonstration of its ancestral origin, the structure and the function of this family of peptides remain poorly known in species as distant as lophotrochozoans. In this study, two GnRH-related peptides (Cg-GnRH-a and CgGnRH-G) were characterized by mass spectrometry from extracts of the visceral ganglia of the Pacific oyster Crassostrea gigas. These peptides showed a high degree of sequence identity with GnRHs of other mollusks and annelids and to a lesser extent with those of vertebrates or with AKH and corazonins of insects. Both the mature peptides and the transcript encoding the...
Tipo: Text Palavras-chave: Mollusk; Bivalve; Oyster; Neuroendocrinology; Reproduction; GnRH.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00079/19003/17477.pdf
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Characterization of ten microsatellite loci in the blue mussel Mytilus edulis ArchiMer
Lallias, Delphine; Stockdale, Ruth; Boudry, Pierre; Lapegue, Sylvie; Beaumont, Andy R..
Mussels of the genus Mytilus are ecologically and commercially important worldwide, and they form hybrid complexes where their distributions overlap. Allozyme and nuclear markers have bee It Used to investigate their genetics over many years, but successful development of reliable highly valuable microsatellite markers has lagged be hind other shellfish species. We have developed and characterized tell novel microsatellite loci that amplify reliably for the blue mussel Mytilus edulis. The number of alleles among 30 individuals from a wild population (Menai Strait, North Wales UK) ranged between 9 and 29 and the observed heterozygosity between 0.300 and 0.954. Significant heterozygote deficiencies against the Hardy-Weinberg model were observed at 6 out of...
Tipo: Text Palavras-chave: Mytilus edulis; Microsatellites; Universal tailed-primer labeling; Null alleles; Mussels.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/00002/11275/7841.pdf
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Chromosome loss in bi-parental progenies of tetraploid Pacific oyster Crassostrea gigas ArchiMer
Mccombie, Helen; Lapegue, Sylvie; Cornette, Florence; Ledu, Christophe; Boudry, Pierre.
Alterations of chromosome number have been observed in the somatic tissue of Crassostrea gigas diploids and artificial polyploids. Tetraploid oysters with abnormal chromosome numbers in some or all of their tissue are considered undesirable as parents either for triploids (produced via a cross with diploids and of aquacultural interest) or for tetraploid breeding. Aneuploid tetraploid oysters may confer the tendency to lose chromosomes and to revert to lower ploidy levels to their offspring. More directly, their offspring could have a lower ploidy because of potential links between somatic and gametic chromosome loss. The present study evaluated the phenomenon in six bi-parental tetraploid families bred from parents of differing somatic ploidy quality. The...
Tipo: Text Palavras-chave: Crassostrea gigas; Mitosis; Chromosome; Cytogenetics; Aneuploid; Polyptoid; Tetraploid; Oyster.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/2005/publication-633.pdf
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Chromosome loss in tetraploid families of the Pacific oyster Crassostrea gigas ArchiMer
Mccombie, Helen; Lapegue, Sylvie; Cornette, Florence; Ledu, Christophe; Boudry, Pierre.
Alterations of chromosome number have been observed in the somatic tissue of Crassostrea gigas diploids and artificial polyploids bred in this species. Tetraploid animals with lower chromosome counts in some or all of their somatic tissue are considered undesirable as parents either for commercial triploids (produced via a cross with diploids) or for tetraploid breeding because (1) they may confer the tendency to lose chromosomes and revert to lower ploidy levels to their offspring or (2) their offspring could have a lower ploidy directly because of potential links between somatic and gametic chromosome loss. The present study evaluated the phenomenon in bi-parental tetraploid families bred from parents of differing ploidy quality, including a...
Tipo: Text Palavras-chave: Tetraploid; Chromosome; Genetic; Crassostrea gigas; Oyster.
Ano: 2003 URL: http://archimer.ifremer.fr/doc/2003/acte-3435.pdf
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Combining Two-Stage Testing and Interval Mapping Strategies to Detect QTL for Resistance to Bonamiosis in the European Flat Oyster Ostrea edulis ArchiMer
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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Comparative analysis of oxygen consumption rates between cupped oyster spat of Crassostrea gigas of French, Japanese, Spanish and Taiwanese origins ArchiMer
Goulletquer, Philippe; Wolowicz, Maciej; Latala, Adam; Geairon, Philippe; Huvet, Arnaud; Boudry, Pierre.
Respiration rates of various geographical strains of Crassostrea gigas were compared to assess the respiratory expenditure as a physiological indicator of catabolism (cost of maintenance). Parental oysters, sampled in France (Marennes-Oleron), Japan (Hiroshima), Taiwan (Tunkang) and Spain (Cadix), were differentiated by both their geographic origin and by mitochondrial DNA markers, allowing the distinction between the two closely related taxa Crassostrea gigas and Crassostrea angulata. After reproduction of these parental oysters, respiration rates of spat of each strain, reared under common controlled conditions, were individually estimated at 20 degrees C by using a volumetric microrespirometer. Our results demonstrated that physiological variability...
Tipo: Text Palavras-chave: Pacific Ocean; NE Atlantic; Oyster strains; Hybrids; Crassostrea angulata; Crassostrea gigas; Metabolism; Respiration rates; Océan Pacifique; Atlantique NE; Souches génétiques; Hybrides; Crassostrea angulata; Crassostrea gigas; Métabolisme; Taux de respiration.
Ano: 1999 URL: http://archimer.ifremer.fr/doc/1999/publication-859.pdf
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Comparative histological study of gametogenesis in diploid and triploid pacific oysters (Crassostrea gigas) reared in an estuarine farming site in France during the 2003 heatwave ArchiMer
Normand, Julien; Le Pennec, Marcel; Boudry, Pierre.
We compared the temporal dynamics of gametogenesis in diploid and triploid Pacific oysters (Crassostrea gigas) using histology. Oysters were reared in an estuarine farming site in Brittany over 3 years and their gametogenesis was monitored over the exceptionally hot summer of 2003. Both diploids and triploids showed active gametogenesis, but a high proportion of triploids remained at early stages of gonad development. Gametogenesis of triploids was characterized by the simultaneous occurrence of gonias and immature cytes together with mature gametes rather than overall retardation, though some triploids showed complete gonad maturation. Evidence of spawning was seen in both groups, and the quantity of germinal products emitted appeared to be similar in...
Tipo: Text Palavras-chave: Triploidy; Crassostrea gigas; Oyster; Gametogenesis.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-4152.pdf
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Comparative karyological study of cupped oyster species ArchiMer
Leitao, Alexandra; Boudry, Pierre; Labat, Jean-philippe; Thiriot-quievreux, Catherine.
Chromosomes of six cupped oyster species were studied using karyometric analysis alter conventional Giemsa staining, and silver staining, Karyotypes of Crassotrea angulata (nine metacentric and one submetacentric chromosome pairs), C. sikamea (nine metacentric and one submetacentric chromosome pairs), C. virginica (eight metacentric and two submetacentric chromosome pairs), C, ariakensis (eight metacentric and two submetacentric chromosome pairs), C, gasar (six metacentric and four submetacentric chromosome pairs), and Saccostrea commercialis (eight metacentric and two submetacentric chromosome pairs) are distinguishable by the number and position of the submetacentric chromosome pair and by the location of nucleolus organizer regions, Comparative...
Tipo: Text Palavras-chave: Bivalvia; Cytotaxonomy; Karyotype; Chromosome; Cupped oyster.
Ano: 1999 URL: http://archimer.ifremer.fr/doc/1999/publication-2737.pdf
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Comparative study of shell shape and muscle scar pigmentation in the closely related cupped oysters Crassostrea angulata, C. gigas and their reciprocal hybrids ArchiMer
Batista, Frederico; Ben-hamadou, Radhouan; Fonseca, Vera; Taris, Nicolas; Ruano, Francisco; Reis-henriques, Maria; Boudry, Pierre.
The taxonomic status of the cupped oysters Crassostrea angulata and C. gigas has received considerable attention in the last decades. Based on larval shell morphology, experimental hybridization, allozymes and nuclear DNA studies several authors have considered these two taxa as being synonymous. However, mitochondrial data showed clear genetic differences between the two taxa. In addition, microsatellite-based studies and cytogenetic studies have also provided evidence that supports their differentiation. Considerable differences have also been observed at the phenotypic level in terms of growth rate and ecophysiological parameters. In the present study, C. angulata from Sado estuary (Portugal) and C. gigas from Seudre estuary (France) were collected and...
Tipo: Text Palavras-chave: Crassostrea gigas; Crassostrea angulata; Hybridization; Shell pigmentation; Shell morphology.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-3904.pdf
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Conséquences génétiques de la production de larves d'huîtres en écloserie : étude des processus de dérive et de sélection ArchiMer
Taris, Nicolas; Sauvage, Christopher; Batista, Frederico; Baron, Sophie; Ernande, Bruno; Haffray, Pierrick; Boudry, Pierre.
Previous studies have shown heritable variation in larval developmental traits in the Pacific oyster Crassostrea gigas. In order to study the genetic consequences of production of oyster larvae in hatcheries, two factors, specific to hatcheries, were examined: the effect of discarding the smallest larvae (i.e. culling) and the effect of temperature (20°C versus 26°C). A mixed-family approach was used in order to infer the genetic composition of larval populations and family assignment, limiting possible environmental bias and allowing the study of a relatively large number of families using a limited number of larval tanks. Our results show that three multiplexed highly polymorphic microsatellite markers are a powerful tool for family assignment and,...
Tipo: Text Palavras-chave: Hatchery; Genetic diversity; Selection domestication; Larvae; Crassostrea gigas; Ecloserie; Diversité génétique; Sélection domestication; Larve; Crassostrea gigas.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/acte-1505.pdf
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Contrasted survival under field or controlled conditions displays associations between mRNA levels of candidate genes and response to OsHV-1 infection in the Pacific oyster Crassostrea gigas ArchiMer
Normand, Julien; Li, Ronghua; Quillien, Virgile; Nicolas, Jean-louis; Boudry, Pierre; Pernet, Fabrice; Huvet, Arnaud.
Pacific oyster Crassostrea gigas suffers from chronic or sporadic mortality outbreaks worldwide, resulting from infectious diseases and/or physiological disorders triggered by environmental factors. Since 2008, ostreid herpesvirus OsHV-1 μVar has been identified as the main agent responsible for mass mortality of juvenile oysters in Europe. Previous studies of genome-wide expression profiling have provided candidate genes that potentially contribute to genetically-based resistance to summer mortality. To assess their value in determining resistance to the juvenile mass mortality that has occurred in France since 2008, we analyzed the expression of 17 candidate genes in an experimental infection by OsHV-1 μVar, and in an in vivo field experiment. Individual...
Tipo: Text Palavras-chave: Molluscs; Gene expression profiling; Inhibitor of kappa B; Summer mortality; Ostreid herpesvirus.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00177/28823/27325.pdf
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Contrôle de la gamétogénèse des huîtres creuses et plates. Relations "reproduction" et "génétique" ArchiMer
Gerard, Andre; Naciri-graven, Yamama; Boudry, Pierre; Launey, Sophie; Heurtebise, Serge; Ledu, Christophe; Phelipot, Pascal.
At the end of the 1980s, after two decades of aquaculture research in molluscs, Ifremer initiated its first genetic studies. These new studies quickly revealed the limits of knowledge in aquaculture, particularly in terms of controlling oyster reproduction. This presentation attempts to summarize the available information on genetics in aquaculture. In particular, breeding practices in the 1980s involved populations of broodstock, while genetics requires modern techniques where individuals, not just populations, can be identified. Controlling reproduction at the individual level in oysters raises new questions that existing protocols cannot address, especially in terms of controlling sex determination, individual maturity, spawning synchrony, chemical...
Tipo: Text Palavras-chave: Gamètes; Fécondation; Induction ponte; Reproducteur; Conditionnement; Gamétogénèse; Génétique; Reproduction; Crassostrea gigas; Huîtres.
Ano: 1995 URL: http://archimer.ifremer.fr/doc/1995/acte-3210.pdf
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Cytogenetic study of Ostrea conchaphila (Mollusca : Bivalvia) and comparative karyological analysis within Ostreinae ArchiMer
Leitao, Alexandra; Chaves, Raquel; Santos, Sara; Boudry, Pierre; Guedes Pinto, Henrique; Thiriot Quievreux, Catherine.
Chromosome preparations of the Olympia oyster Ostrea conchaphila Carpenter were studied using conventional Giemsa, silver staining, and C-banding techniques. The karyotype consists of six metacentric (1, 2, 4, 6, 8, and 10) and four submetacentric (3, 5, 7, 9) chromosome pairs. The silver-stained nucleolus organizer regions (Ag-NORs) were terminally located on the short arms of the submetacentric pair 5 (56% of cases) and on the long arms of submetacentric pair 7 (6% of cases). Constitutive heterochromatin was observed as telomeric C-bands on the short arm of the NOR-bearing chromosome pair 5 and as centromeric blocks of several chromosome pairs. Comparative analysis of patterns of karyotype, Ag-NORs, and C-bands of this species and of five other flat...
Tipo: Text Palavras-chave: Ostreinae; Cytotaxonomy; Cytogenetics; Ostrea conchaphila.
Ano: 2002 URL: https://archimer.ifremer.fr/doc/2002/publication-2792.pdf
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De novo assembly and annotation of the European abalone Haliotis tuberculata transcriptome ArchiMer
Harney, Ewan; Dubief, Bruno; Boudry, Pierre; Basuyaux, Olivier; Schilhabel, Markus B.; Huchette, Sylvain; Paillard, Christine; Nunes, Flavia.
The European abalone Haliotis tuberculata is a delicacy and consequently a commercially valuable gastropod species. Aquaculture production and wild populations are subjected to multiple climate-associated stressors and anthropogenic pressures, including rising sea-surface temperatures, ocean acidification and an emerging pathogenic Vibrio infection. Transcript expression data provides a valuable resource for understanding abalone responses to variation in the biotic and abiotic environment. To generate an extensive transcriptome, we performed next-generation sequencing of RNA on larvae exposed to temperature and pH variation and on haemolymph of adults from two wild populations after experimental infection with Vibrio harveyi. We obtained more than 1.5...
Tipo: Text Palavras-chave: RNA-Seq; Mollusca; Gastropoda; Development; Vibrio harveyi; Climate change.
Ano: 2016 URL: https://archimer.ifremer.fr/doc/00318/42940/45103.pdf
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Défi MOREST - Mortalités estivales de l'huître creuse Crassostrea gigas - Caracterisation des facteurs de risques associés au mortalités estivales - Synthèse du thème IVA - Etude des bases génétiques de la mortalité estivale du naissain et des possibilités d'amélioration de la survie par sélection. (La Rochelle 14- 15 mars 2006) ArchiMer
Boudry, Pierre.
Malgré l'importance économique de la production de I'huître creuse Crassostrea gigas en France et dans le monde, cette espèce n'a encore que peu bénéficié des améliorations observées chez la quasi-totalité des espèces d'intérêt agricole et un nombre croissant d'espèces d'intérêt aquacole. Le principal apport de la génétique à l'amélioration de la production de cette espèce consiste en la production d'individus triploïdes (pour revue voir Nell, 2002). Chez les huîtres, les principaux objectifs des programmes de sélection ont été classés par Mahon (1983) en quatre groupes principaux par caractères d'intérêts : (a) caractères liés à la ponte et au développement larvaire ; (b) amélioration de la survie et de la croissance de la fixation à la taille commerciale...
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Ano: 2006 URL: http://archimer.ifremer.fr/doc/00304/41534/40742.pdf
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Detailed insights into pan-European population structure and inbreeding in wild and hatchery Pacific oysters (Crassostrea gigas) revealed by genome-wide SNP data ArchiMer
Vendrami, David L. J.; Houston, Ross D.; Gharbi, Karim; Telesca, Luca; Gutierrez, Alejandro P.; Gurney-smith, Helen; Hasegawa, Natsuki; Boudry, Pierre; Hoffman, Joseph I..
Cultivated bivalves are important not only because of their economic value, but also due to their impacts on natural ecosystems. The Pacific oyster (Crassostrea gigas) is the world's most heavily cultivated shellfish species and has been introduced to all continents except Antarctica for aquaculture. We therefore used a medium-density single nucleotide polymorphism (SNP) array to investigate the genetic structure of this species in Europe, where it was introduced during the 1960s and has since become a prolific invader of coastal ecosystems across the continent. We analyzed 21,499 polymorphic SNPs in 232 individuals from 23 localities spanning a latitudinal cline from Portugal to Norway and including the source populations of Japan and Canada. We confirmed...
Tipo: Text Palavras-chave: Aquaculture; Crassostrea gigas; Genetic structure; High-density genotyping array; Inbreeding; Pacific oyster; Restriction site-associated DNA (RAD) sequencing; Single nucleotide polymorphism (SNP).
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00484/59561/62557.pdf
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Detection of ostreid herpesvirus 1 DNA by PCR in bivalve molluscs: A critical review ArchiMer
Batista, Frederico; Arzul, Isabelle; Pepin, Jean-francois; Ruano, Francisco; Friedman, Carolyn S.; Boudry, Pierre; Renault, Tristan.
Herpes-like viral infections have been reported in different bivalve mollusc species throughout the world. High mortalities among hatchery-reared larvae and juveniles of different bivalve species have been associated often with such infections. The diagnosis of herpes-like viruses in bivalve molluscs has been performed traditionally by light and transmission electron microscopy. The genome sequencing of one of these viruses, oyster herpesvirus 1 (OsHV-1), allowed the development of DNA-based diagnostic techniques. The polymerase chain reaction (PCR) has been used for the detection of OsHV-1 DNA in bivalve molluscs at different development stages. In addition, the PCR used for detection of OsHV-1 has also allowed the amplification of DNA from an OsHV-1...
Tipo: Text Palavras-chave: Oyster; Bivalve molluscs; PCR; Detection; OsHV 1; Herpesvirus.
Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-2322.pdf
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Detection of ostreid herpesvirus-1 (OsHV-1) by PCR using a rapid and simple method of DNA extraction from oyster larvae ArchiMer
Batista, Frederico; Taris, Nicolas; Boudry, Pierre; Renault, Tristan.
A DNA extraction procedure was developed for the detection of ostreid herpesvirus-1 (OsHV-1) using the polymerase chain reaction (PCR) in oyster larvae. The DNA extraction procedure developed was tested on 8 larval samples. Abnormal nuclei with characteristic features associated with OsHV-1 infections were only observed in samples in which the viral DNA was detected by PCR. A previously described competitive PCR method was applied to detect inhibition during PCR reactions. The results show that the method can be used on small amounts of oyster larvae (3 mg) for the detection of OsHV-1 DNA by PCR.
Tipo: Text Palavras-chave: DNA extraction; Detection; Larvae; Oyster; OsHV 1; Herpesvirus.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/2005/publication-2916.pdf
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Development of SNPs and their use for the identification of summer mortality resistance QTLs in the Pacific oyster (Crassotrea gigas) ArchiMer
Sauvage, Christopher; Lapegue, Sylvie; Bierne, Nicolas; Boudry, Pierre.
Summer mortalities of the Pacific cupped oyster Crassostrea gigas have been described in the literature for decades. One solution to overcome this problem would be to select animals more tolerant to summer mortalities, as this trait was shown to be highly heritable (Degrémont, 2003). The identification of markers associated to the resistance would allow to better understand this complex phenomenon and, eventually to establish markers assisted selection. Recently, two moderately dense genetic linkage maps have been established in the Pacific oyster based on microsatellites and AFLP markers (Hubert and Hedgecock, 2004; Li and Guo, 2004). In this context, the development and mapping of SNPs will increase the density of the linkage map and consequently the...
Tipo: Text Palavras-chave: QTLs analyses; Summer mortaliy; Genetic; SNPs; Crassostrea gigas; Oyster.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/acte-3351.pdf
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