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Registros recuperados: 70 | |
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Boudry, Pierre; Barre, Marc; Gerard, Andre. |
Despite the economic importance of shellfish, genetic improvement has not yet had a great impact on these species. Shellfish farming is traditionally based on wild species whose natural populations are often overexploited and do not fulfill market demand. Up to now, the most effective answer to disease problems or for the improvement of productivity has been the introduction of new species. However, the introduction of new species is constrained by their ecological impact and is also limited by the availability of suitable species. Genetic improvement of local species should therefore be of great importance as a viable alternative for the long term sustainability of the shellfish industry. The different approaches to genetic improvement include... |
Tipo: Text |
Palavras-chave: Selective breeding; Hybridization; Polyplidy; Introduction; Oysters; Selection; Hybridation; Polyploidie; Introduction; Huitres. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/1997/acte-3499.pdf |
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Gajardo, G.; Mercado, C.; Beardmore, J.A.; Sorgeloos, P.. |
An <i>Artemia</i> population from a site recently described in Chile and located in a semi-arid and humid hydrographical zone (Torres del Paine National Park), was electrophoretically characterized and cross-bred (followed through <i>F</i><sub>3</sub>) to reference samples of <i>A. franciscana</i> (San Francisco Bay, California, USA) and <i>A. persimilis</i> (Buenos Aires, Argentina), which are the species most likely to be found in Chile. The population exhibited high levels of genetic variability as judged by the percentage of polymorphic loci (<i>P</i>=53.3), mean number of alleles per locus (<i>n</i>=2.2) and mean heterozygosity (<i>H</i>=0.176). Based on... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allopatric populations; Allozymes; Genetic isolation; Hybridization; Population genetics; Chile. |
Ano: 1999 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=4016 |
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Huvet, Arnaud; Gerard, Andre; Ledu, Christophe; Phelipot, Pascal; Heurtebise, Serge; Boudry, Pierre. |
The distinction of the two cupped oysters Crassostrea gigas (Thunberg, 1793) and Crassostrea angulata (Lamark, 1819) into two species was chiefly due to their differing geographical distributions, C. gigas being present in Asia and C. angulata in Europe. Today it is commonly accepted that C. angulata and C. gigas are a single species according to morphological, genetic and F1 hybridization data. However, the demonstration of the fertility of their hybrids and the absence of any reproductive isolation remained to be investigated. Consequently, we studied the fertility of hybrids and sperm competition by performing three different experiments and producing G1 and G2 hybrid progenies between wild populations of C. angulata and C. gigas. Progenies showed very... |
Tipo: Text |
Palavras-chave: Crassostrea angulata; Crassostrea gigas; Developmental yields of larvae; Fertility; Controlled crosses; Hybridization. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/publication-1395.pdf |
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Azevedo,MFC; Foresti,F.; Ramos,PRR; Jim,J. |
Specimens of Bufo ictericus, Bufo paracnemis and a third type, considered an intermediate subgroup between these species, were cytogenetically studied by conventional Giemsa staining, C-banding and staining of the nucleolus organizer region (NOR). The nuclear DNA content and seroproteins were also analyzed to characterize these species, and verify the possibility of hybridization between them. Karyotypes and cytogenetic markers were essentially equal on the basis of the methods used. The DNA nuclear content found was 6.25 ± 0.30 pg/DNA in Bufo ictericus; 7.57 ± 0.40 pg/DNA in Bufo paracnemis and 7.04 ± 0.29 pg/DNA in the intermediate subgroup. Eletrophoresis of total blood serum in Bufo ictericus, Bufo paracnemis and the intermediate specimens revealed a... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bufo; Hybridization; Cytogenetics; Nuclear DNA; Seroproteins. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300012 |
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Huvet, Arnaud; Fabioux, Caroline; Mccombie, Helen; Lapegue, Sylvie; Boudry, Pierre. |
The marine environment is of special interest for studying hybridization between closely related taxa because of the high dispersal potential of planktonic larvae, such as those of most bivalve species. The oysters Crassostrea angulata and C. gigas are known to be very close genetically and entirely inter-fertile under controlled conditions. However, hybridization in the wild had not been investigated, mainly due to the lack of nuclear diagnostic markers. In the present paper, we first estimated genetic differentiation between these 2 closely related taxa using 8 microsatellite markers. Interestingly, 5 markers displayed significant differences of allele size between taxa. The subsequent sequencing of alleles of one of these microsatellites showed several... |
Tipo: Text |
Palavras-chave: Allele size; Microsatellites; Genetic differentiation; Hybridization; Crassostrea gigas; Crassostrea angulata. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-3355.pdf |
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Batista, Frederico; Boudry, Pierre; Lapegue, Sylvie; Heurtebise, Serge; Monteiro, C. C.. |
The Portuguese oyster, Crassostrea angulata, was introduced from Portugal to the French Atlantic Coast in the 1860s. C. angulata quickly settled and expanded and leaded to the development of a new aquacultural industry in France. In the late 1960s, mortality associated with the detection of an iridovirus, led to the wipe out of C. angulata from French Atlantic waters and to the massive introduction of C. gigas to sustain production. In Southern Europe, similar symptoms were also observed in natural stocks of C. angulata from Sado River (Portugal) and from the area of Cadiz (Spain). Nowadays, only very few «pure» populations of C. angulata remain in southern Europe. These populations are potentially endangered by the current expansion of C. gigas... |
Tipo: Text |
Palavras-chave: Selection; Hybridization; Settlement pattern; Population genetic; Genetic; Oysters; Crassostrea angulata; Crassostrea gigas. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3310.pdf |
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Registros recuperados: 70 | |
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