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Registros recuperados: 77 | |
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Gras, Marie-paule. |
The mortality that decimated Portuguese oysters, C. angulata, in 1970-1971, up to 80% in most sectors, required the introduction of C. gigas oysters resistant to disease and whose reproduction proved itself to be excellent (GRAS and assoc. 1971). Artificial beds of Pacific oysters were created. Nonetheless, in some areas, there continued to be small populations of C. angulata that, mixed in with the C. gigas oysters that had been brought in, participated in reproduction. Genetic problems then arose, among which the selection of specimens and hybridisation were to be considered more specifically. There are, in fact, two cases of hybridisation. |
Tipo: Text |
Palavras-chave: Génétique; Hybridation; Huîtres; Crassostrea angulata; Crassostrea gigas. |
Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/acte-2987.pdf |
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Boudry, Pierre; Huvet, Arnaud; Fabioux, Caroline; Lapegue, Sylvie. |
Crassostrea angulata and Crassostrea gigas, two cupped oyster taxa of Asian origin (O'Foighil et al, 1998), were successively introduced into Europe during the XVIth and the XXth century respectively (Héral and Grizel, 1991). To date, populations presumed to be C. angulata remain only in the south of Spain and Portugal, while the geographic range of C. gigas is expending, notably due to aquaculture. The two taxa can be distinguished by RFLP analysis of the mitochondrial Cytochrome Oxydase I locus (COI). This marker revealed strong genetic differentiation between Asian populations of the two taxa (Boudry et al., 1998). In contrast, nuclear markers showed a much lower genetic differentiation (Huvet et al, in press). The absence of any reproductive barrier... |
Tipo: Text |
Palavras-chave: Microsatellite; Genetic; Crassostrea angulata; Crassostrea gigas; Oysters. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/acte-3453.pdf |
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Lapegue, Sylvie; Batista, Frederico; Heurtebise, Serge; Yu, Ziniu; Boudry, Pierre. |
The Pacific oyster, Crassostrea gigas (Thunberg), and the Portuguese oyster, C. angulata (Lamarck), are two closely related taxa. Although these two taxa were both introduced from Asia into Europe. one (C. gigas) was voluntarily introduced in the early 1970s, whereas the other (C. angulata) was presumed to be present in Europe for at least four centuries, but nearly disappeared because of disease. Few C. angulata populations remained in southern Portugal, Spain and Morocco and their putative origin was traced in Taiwan. The present paper reports evidence for its presence in Northern China. We reanalyzed recently published mitochondrial cytochrome oxidase C subunit I (COI) sequence data from presumed Dalianwan oysters (C. talienwhanensis) and compared them... |
Tipo: Text |
Palavras-chave: Phylogeography; Cytochrome oxidase C subunit 1 gene; Crassostrea talienwhanensis; Gigas; Crosstrea; Crassostrea angulata; Cupped oysters. |
Ano: 2004 |
URL: https://archimer.ifremer.fr/doc/2004/publication-3173.pdf |
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Comps, Michel; Gras, Paul. |
A year after the end of the Gill disease which heavily struck the Portuguese oysters Cassostrea angulata Lmk. (Marteil, 1968), a new disease whose causes are still unexplained caused a massive mortality in the same species in the summer of 1970 (Comps, 1972). It can be considered, in 1973, that the successive losses lead to the quasi-extinction of the species C. angulata in the farms of the Marennes basin, since, contrary to what has been done in the case of the Malpèque disease in Canada, the indigenous specious was replaced by another species, the Pacific oyster Crassostrea gigas Thunberg. |
Tipo: Text |
Palavras-chave: Marennes Oléron; Huîtres; Mortalité; Crassostrea angulata. |
Ano: 1973 |
URL: http://archimer.ifremer.fr/doc/1973/acte-5927.PDF |
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Deltreil, Jean-pierre. |
A peine l'ostréiculture se relevait-elle des dommages causés en 1967-1968 par ce qu'on a appelé la "maladie des branchies" qu'une deuxième épizootie décimait en 1971 les populations de C. angulata sur l'ensemble du littoral français. Cette situation rappelle celle qu'avait connue O. edulis vers 1920 dont la mortalité avait favorisé l'extension de C. angulata; cinquante ans plus tard, l'ostréiculture a du s'orienter rapidement vers une autre espèce, C. gigas. Nous décrivons l'allure des phénomènes de mortalité et les conséquences qui en ont résulté dans les régions ostréicoles du bassin d'Arcachon et de l'estuaire de la Gironde. |
Tipo: Text |
Palavras-chave: Ostréiculture; Crassostrea angulata; Mortalité; Bassin Arcachon; Estuaire Gironde. |
Ano: 1973 |
URL: http://archimer.ifremer.fr/doc/00015/12630/9519.pdf |
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Riesco, Marta F.; Felix, Francisca; Matias, Domitilia; Joaquim, Sandra; Suquet, Marc; Cabrita, Elsa. |
Sperm cryopreservation is a widely employed technique that promotes alternative techniques to contribute to broodstock management or restoration programs for species of commercial interest, endangered species or species with an interesting genotype. The preservation of genetic material from improved stocks or from the original population is extremely important for the oyster aquaculture industry to prevent the potential impacts of epidemic diseases and natural disasters. The Portuguese oyster, Crassostrea angulata, was the most important species commercialized by the shellfish industry. However, inadequate management of this industry and pathology occurrences resulted in a significant decrease in natural populations. For this reason, in this work a... |
Tipo: Text |
Palavras-chave: Crassostrea angulata; Sperm; Cryopreservation; Motility; Viability; Fertilization. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00333/44432/44098.pdf |
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Alderman, D. J.; Gras, Paul. |
During April and May of this year, there has been a heavy mortality of Portuguese oysters, Crassostrea angulata LmK., which were imported into Britain from the River Tagus (Portugal) in March. Losses in some cases exceeded 90 per cent. The symptoms shown by the dyring oysters are the same as those seen in Britain and France in C. angulata in 1967 and 1968. Farley described the general symptoms in oysters (C. virginica Gmelin) dying of prolonged functional or infectious disease. These gross symtoms appear to be similar in the case of several different diseases including the present European mortality. |
Tipo: Text |
Palavras-chave: Gill; Crassostrea angulata; Oysters. |
Ano: 1969 |
URL: http://archimer.ifremer.fr/doc/1969/publication-5931.PDF |
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Huvet, Arnaud; Fabioux, Caroline; Lapegue, Sylvie; Boudry, Pierre. |
Crassostrea angulata and Crassostrea gigas, two cupped oysters of Asian origin (O'Foighil et al, 1998), have been introduced successively in Europe during the XVlth and the XXth century (Grizel et Héral, 1991). The present populations of C. angulata appear to be limited to the south of Spain and Portugal, whereas the distribution of C. gigas in Europe is rising because of the development of oyster farming. The distinction between the two subspecies in based on a RFLP marker of the mitochondrial genome (COI) which shows a strong genetic differentiation between the two subspecies populations (Boudry et al., 1998). On the contrary, the nuclear markers (microsatellites) showed a smaller genetic differentiation between them (Huvet et al, under press). The... |
Tipo: Text |
Palavras-chave: Microsatellite; Hybridation; Crassostrea angulata; Crassostrea gigas; Huîtres; Génétique. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/acte-3282.pdf |
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Batista, Frederico; Fonseca, Vera; Ben-hamadou, Radhouan; Taris, Nicolas; Henriques, Maria; Boudry, Pierre. |
Unlike in some crops, no large heterotic effects have been observed in most farmed animals. Interestingly, significant hybrid vigour for some traits has been reported in the Pacific oyster, Crassostrea gigas. Crossbreeding between closely related taxa can be seen as an efficient way to exploit the dominance component of the genetic variance of a trait. Factorial crosses between the Portuguese oyster C. angulata (from Sado estuary, Portugal) and C. gigas (from Seudre estuary, France) were done to evaluate the aquaculture potential of hybrids. Juveniles of the different progenies were reared in Ria Formosa (Portugal) under usual farming conditions. The genetic confirmation of all progenies was done using mitochondrial and nuclear markers in order to detect... |
Tipo: Text |
Palavras-chave: Hybridization; Crassostrea angulata; Crassostrea gigas; Genetic; Oyster. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-3429.pdf |
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Grizel, Henri. |
Two successive diseases struck the flat oyster Ostrea edulis farms in Brittany. These two epizooties lead to some changes in the farming practices. The oyster culture developed towards the open ocean, in the sublitoral part. New techniques have been developed for the culture and collection. The flat oyster has been partially replaced by the cupped oyster Crassostrea gigas whose production went from 3 000 to 16 000 tonnes. They also had heavy consequences on the regional economy. The important mortalities decimated the stocks. The production dropped by about 17 000 tonnes from 1910 to 1982. For the same period of time, profits from the sale of the produced flat oysters dropped from 131.6 million to 65.2 million francs. Numerous companies reduced the surface... |
Tipo: Text |
Palavras-chave: Bonamia ostreae; Marteilia refringens; Crassostrea gigas; Crassostrea angulata; Ostrea edulis; Huître; Pathologie. |
Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/1983/acte-5924.PDF |
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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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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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Comps, Michel; Bonami, Jean-robert; Vago, C.; Razet, Daniel. |
Among the major epizootics known in marine Molluscs, the one that started on the coasts of Europe in 1970 in the Portuguese oyster, Crassostrea angulata, was certainly one of the largest due to its range and due to the economic loss sustained by the French oyster farming as a whole. It led to the disappearance of the species C. angulata as a farmed oyster, and to the massive introduction of the Japanese oyster, C. gigas, known to be resistant to the disease. From the first manifestations of this epizootic, the laboratories of the ISTPM were actively dedicated to its etiology. Now, after several years, a study begun at the La Tremblade laboratory has just been completed. |
Tipo: Text |
Palavras-chave: Marennes Oléron; Mortalités; Histologie; Epizootie; Crassostrea angulata. |
Ano: 1976 |
URL: http://archimer.ifremer.fr/doc/1976/publication-2995.pdf |
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Huvet, Arnaud; Lapegue, Sylvie; Magoulas, A; Boudry, Pierre. |
The respective status of the Portuguese oyster, Crassostrea angulata, and the Pacific oyster, Crassostrea gigas, has long been a matter of controversy. Morphological and physiological similarities, homogeneity of allozyme allelic frequencies between populations of the two taxa and the demonstration of hybridization lead most authors to suggest that they should be regrouped within the same species. The risk of introgression and the present expansion of C. gigas aquaculture in Europe raises the question of the need for preservation of C. angulata in Europe, as only a few populations remain. We studied European and Asian populations of C. gigas and C. angulata using microsatellite and mitochondrial DNA markers to estimate their genetic diversity and... |
Tipo: Text |
Palavras-chave: Phylogeography; Population genetics; Microsatellites; Crassostrea gigas; Crassostrea angulata. |
Ano: 2000 |
URL: https://archimer.ifremer.fr/doc/2000/publication-707.pdf |
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Boudry, Pierre; Huvet, Arnaud. |
The taxonomic status of Crassostrea angulata and Crassostrea gigas has long been a matter of controversy. Morphological and physiological similarities, as well as homogeneity in allelic frequencies on allozymes between the populations of the two taxa, lead most authors to suggest to regroup of the two within the same species. European and Asian populations of C. gigas and C. angulata have been studied using microsatellite and mitochondrial DNA markers. The analysis of genetic distances and the distribution of allelic and haplotype frequencies revealed a differentiation between the populations of C. gigas and C. angulata. The data allowed the construction of Neighbor-joining trees for each of the two types of markers. Similar topologies appeared with data... |
Tipo: Text |
Palavras-chave: Mitochondrial DNA; Nuclear DNA; Phylogeography; Crassostrea angulata; Crassostrea gigas; Genetic; Oyster. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/acte-3434.pdf |
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Registros recuperados: 77 | |
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