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Registros recuperados: 41 | |
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Teaniniuraitemoana, Vaihiti; Huvet, Arnaud; Levy, Peva; Klopp, Christophe; Lhuillier, Emeline; Gaertner-mazouni, Nabila; Gueguen, Yannick; Le Moullac, Gilles. |
Background Black pearl farming is based on culture of the blacklip pearl oyster Pinctada margaritifera (Mollusca, lophotrochozoa), a protandrous hermaphrodite species. At first maturation, all individuals are males. The female sex appears progressively from two years old, which represents a limitation for broodstock conditioning for aquaculture production. In marine mollusks displaying hermaphroditic features, data on sexual determinism and differentiation, including the molecular sex determining cascade, are scarce. To increase genomic resources and identify the molecular mechanisms whereby gene expression may act in the sexual dimorphism of P. margaritifera, we performed gonad transcriptome analysis. Results The gonad transcriptome of P. margaritifera... |
Tipo: Text |
Palavras-chave: Pinctada margaritifera; Gametogenesis; Transcriptome; Differential expression; Sex determinism. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00201/31194/29593.pdf |
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Soletchnik, Patrick; Ropert, Michel; Bedier, Edouard; Costil, K. S.; Dubois, Brice; Degremont, Lionel; Bouget, Jean-francois; Martin, Jean-louis; Enriquez-diaz, M.; Faury, Nicole; Le Moine, Olivier; Renault, Tristan; Gagnaire, Beatrice; Huvet, Arnaud; Moal, Jeanne; Samain, Jean-francois. |
Field characterization of summer mortality was performed in France in the frame of the Morest project. Natural and hatchery spat were compared between three oyster production areas in France. Regardless of the natural or hatchery origin, oysters died during the reproduction period after temperature reaches 19 degree C. Thus, in southern areas, temperature accelerated gametogenesis of small spat (10mm) as well as adults, and mortality appeared for the two age classes. In contrast, sexual maturation proceeded more slowly in northern where spat mortality was lower compared to 18 months old oysters. However, critical gametogenesis and temperature were not sufficient to induce mortalities, as observed in examples with stable environment. Alternatively sediment... |
Tipo: Text |
Palavras-chave: Seasonal variation; Oyster culture; Mortality causes; Hatcheries; Gametogenesis; Environmental factors; Crassostrea gigas; Oysters. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/acte-3348.pdf |
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Deslous-paoli, Jean-marc; Heral, Maurice; Berthome, Jean-paul; Razet, Daniel; Garnier, Jacqueline. |
In summer 1979, the natural reproduction of oysters Crassostrea gigas Thunberg, in Marennes-Oleron basin, produced a large number of juveniles which was not the case in summer 1981. If one compares the evolution of the main constituents of the flesh, one can see that, at the beginning of August, before spawning the male oysters in 1981 contained 6,3% less proteins, 34,2% less lipids and 61,2% less glucids than those in 1979 and respectively 12,3%, 21,3% and 69,8% less as far as females are concerned. The energetic value of ash-free dry flesh of female oysters is nearly the same for the two years whereas for male oysters the value is slightly lower in 1981 than in 1979. The total energetic values of male and female oysters show a slight difference between... |
Tipo: Text |
Palavras-chave: Crassostrea gigas; Seasonal variations; Food availability; Water temperature; Saccharides; Proteins; Lipids; Biochemical composition; Gametogenesis; Spawning; Sexual reproduction. |
Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-1891.pdf |
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Normand, Julien; Ernande, Bruno; Boudry, Pierre. |
Today, triploidy is the most common method used to genetically improve marine bivalve aquaculture production. In the Pacific oyster Crassostrea gigas, triploidy affects many traits. The most proeminent one is reproductive effort, which is greatly reduced compared to diploids. The combined effects of physiological trade-offs between survival, growth and reproduction together with the reduction of reproductive effort in triploids explains the global enhancement of yield observed. However, the sterility of triploid oysters is only partial and some triploid individuals can show normal gametogenesis (i.e. similar to diploids), especially under warm conditions. In diploid oysters, the heritability of reproductive effort has been shown to be relatively low, but a... |
Tipo: Text |
Palavras-chave: Parentage analysis; Triploidy; Oyster; Quantitative genetics; Gametogenesis. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/acte-4525.pdf |
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Jorge Eduardo, Chávez Villalba. |
In France, 90% of the annual cup oyster (Crassostrea gigas) production comes from larvae caught in the Arcachon and Marennes-Oléron basins. However, the spat catch shows many interannual irregularities and oyster farmers increasingly say they need spat outside of the reproductive period. Thus, the role of hatcheries in Japanese oyster spat production in France is becoming increasingly evident. However, the current state of knowledge about cup oyster reproduction in controlled conditions is limited, and hatchery professionals must confront various problems to optimise treatment of genitors so as to obtain larval breeds in good health and a lengthening of the reproductive season. To respond to this, we have carried out a study on three aspects that seem... |
Tipo: Text |
Palavras-chave: Water temperature; Biochemical studies; Gametogenesis; Breeder conditioning; Larval rearing. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/these-1456.pdf |
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Le Moullac, Gilles; Hui, Belinda; Vonau, Vincent; Levy, Peva; Cochard, Jean-claude. |
Preliminary experiments allowed defining basic requirements of Pinctada margaritifera for somatic and gonadic growth in controlled conditions. This study was continued by observation of the gametogenesis at a cellular level. In April/May 2008, 125 oysters were conditioned for 30 days in 25 tubular tanks (30 L). Water was renewed 4 times/hour. A mixed (v:v) diet of Isochrysis galbana (T-Iso) and Chaetoceros gracilis was supplied continuously. A control batch of 125 oysters was maintained in trays in the lagoon. An initial sample of 30 individuals was made. Gonadic changes were first characterized using a gonadal development index (GDI) based on the ratio of the gonad area to the total visceral mass area on a sagittal section of the body. Histological... |
Tipo: Text |
Palavras-chave: Pearl oyster; Reproduction; Gametogenesis; Broodstock. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00029/14010/11196.pdf |
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Guevelou, Eric; Huvet, Arnaud; Galindo-sanchez, Clara E.; Milan, Massimo; Quillien, Virgile; Daniel, Jean-yves; Quere, Claudie; Boudry, Pierre; Corporeau, Charlotte. |
The hermaphrodite Pacific oyster Crassostrea gigas displays a high energy allocation to reproduction. We studied the expression of AMP-activated protein kinase (AMPK) during gametogenesis in the gonad and characterized the mRNA sequences of the AMPK subunits: the AMPK alpha mRNA sequence was previously characterized; we identified AMPK beta, AMPK gamma, and mRNAs of putative AMPK-related targets following bioinformatics mining on existing genomic resources. We analyzed the mRNA expression of the AMPK alpha, beta, and gamma subunits in the gonads of male and female oysters through a reproductive cycle, and we quantified the mRNA expression of genes belonging to fatty acid and glucose metabolism. AMPK alpha mRNA levels were more abundant in males at the... |
Tipo: Text |
Palavras-chave: AMP-activated protein kinase; Crassostrea gigas; Gametogenesis; Marine bivalve; Reproduction. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00168/27911/26470.pdf |
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Gonzales, Ricardo; Quillien, Virgile; Robert, Rene. |
To determine the effects of food quality on Ostrea edulis reproduction, European flat oysters were conditioned during two sets of experiments, carried out in spring and autumn, during 40 days at 19 degrees C, in 50 l transparent flow-through tanks, in triplicate, and fed constantly at 900 mu m(3) mu l(-1), with eight different types of microalgae. Four species were fed per group of trials: Isochrysis affinis galbana, Chaetoceros gracilis, Skeletonema marinoi, and Tetraselmis suecica were fed to flat oysters in the first set; whereas Rhodomonas salina, Thalassiosira weissflogii, Thalassiosira pseudonana, and Pavlova lutheri were provided during the second set of experiments. At the beginning and end of both conditioning periods, oysters were sampled and... |
Tipo: Text |
Palavras-chave: Ostrea edulis; Broodstock conditioning; Gametogenesis; Microalgal diets. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00144/25497/24163.pdf |
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Huvet, Arnaud; Beguel, Jean-philippe; Pereira Cavaleiro, Nathalia; Thomas, Yoann; Quillien, Virgile; Boudry, Pierre; Alunno-bruscia, Marianne; Fabioux, Caroline. |
Feeding strategies and digestive capacities can have important implications for variation in energetic pathways associated with ecological and economically important traits, such as growth or reproduction in bivalve species. Here, we investigated the role of amylase in the digestive processes of Crassostrea gigas, using in vivo RNA interference. This approach also allowed us to investigate the relationship between energy intake by feeding and gametogenesis in oysters. Double-stranded (ds)RNA designed to target the two α-amylase genes A and B was injected in vivo into the visceral mass of oysters at two doses. These treatments caused significant reductions in mean mRNA levels of the amylase genes: −50.7% and −59% mRNA A, and −71.9% and −70.6% mRNA B in 15... |
Tipo: Text |
Palavras-chave: Alpha-Amylase; DsRNA; Gametogenesis; Marine bivalve; Dynamic energy budget. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00271/38239/36422.pdf |
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Fauvel, Christian; Suquet, Marc; Severe, Armelle; Mylonas, Constantinos C.; Papandroulakis, Nikos. |
The potential of wreckfish (Polyprion americanus) to breed in captivity was examined. Ovarian activity varied seasonally, with vitellogenesis beginning in November and ending in May. Slow-release implant with gonadotropin-releasing hormone agonist (GnRHa) prevented atresia, and both GnRHa injections or implants at the end of vitellogenesis triggered ovulation after 7 days. Spontaneous spawning was obtained only in one female, and the few eggs produced were of poor viability. Manual stripping and artificial fertilization produced viable gametes and embryos. Therefore, present captivity conditions inhibited final oocyte maturation (FOM) and spawning, but not vitellogenesis and spermatogenesis. GnRHa treatments stimulate FOM and ovulation of viable eggs. |
Tipo: Text |
Palavras-chave: Aquaculture; Polyprion americanus; Wreckfish; GnRHa; Gametogenesis. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6554.pdf |
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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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Pouvreau, Stephane; Gangnery, Aline; Tiapari, Jerome; Lagarde, Franck; Garnier, Matthieu; Bodoy, Alain. |
The gametogenic cycle and the reproductive effort of the blacklip pearl oyster, Pinctada margaritifera, cultivated in Takapoto lagoon were studied for a 1-year period (March 1997-April 1998) by bimonthly observations of gonadal sections, dry tissue weights and gonadal index in a population of pearl oyster composed of three age-groups. pearl oysters attained sexual maturity in the end of their first year (height approximate to 40 mm), implying that P. margaritifera is a late-maturing species in comparison with other Pteriidae. This species was also confirmed to be a marked protandrous successive hermaphrodite in culture, with 100 % of males at first maturity and 75 % in older pearl oyster (height > 120 mm). The general pattern of gametogenic activity,... |
Tipo: Text |
Palavras-chave: French Polynesia; Reproductive effort; Reproductive cycle; Tropical aquaculture; Gametogenesis; Blacklip pearl oyster; Polynésie française; Effort de reproduction; Cycle de reproduction; Aquaculture tropicale; Gamétogenèse; Huître perlière. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-1391.pdf |
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Le Moullac, Gilles; Soyez, Claude; Sham-koua, Manaarii; Levy, Peva; Moriceau, Jacques; Vonau, Vincent; Maihota, Mayalen; Cochard, Jean-claude. |
This study aimed to model the food intake of P. margaritifera in order to examine the relationship between food level and reproductive activity. The effect of microalgae concentration on ingestion rate and assimilation efficiency was studied over a broad concentration range, using a mixture of Isochrysis galbana and Chaetoceros gracilis. Reproductive effort was assessed using three microalgae concentrations of 0.5, 7 and 18 cell μL-1. Reproductive status was assessed by gonad development index (GDI) – the ratio of the gonad surface to the visceral mass surface – and histological analysis of the gonad based on the presence (continuous or discontinuous) or the absence of gonial cells (GC). Ingestion is a saturating function of seston concentration for... |
Tipo: Text |
Palavras-chave: Pinctada margaritifera; Food level; Ingestion rate; Reproduction; Gametogenesis. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00050/16085/13562.pdf |
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Mcfarland, Katherine; Soudant, Philippe; Jean, Frederic; Volety, Aswani K.. |
Understanding the population dynamics of invasive species, such as the green mussel Perna viridis (Linnaeus, 1758), can aid in explaining the success of newly introduced populations and help predict the potential for spread. During a two-year field study of established populations in the invaded region of southwest Florida, year round gametogenesis and continuous spawning capabilities were observed through histological analysis of mussels collected monthly. This was supported by overall stable energetic reserves as measured through proximal biochemical composition (protein, glycogen and lipid content). However, egg outputs in the summer (6.4 x 10(6) +/- 2.6 x 10(6) eggs / female) were significantly higher than egg outputs of winter-spawned mussels (7.7 x... |
Tipo: Text |
Palavras-chave: Gametogenesis; Protein; Glycogen; Lipid; Induced spawning. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00616/72842/72974.pdf |
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Burgeot, Thierry; Quirion, Sophie; Quiniou, Francoise; Knoery, Joel; Soletchnik, Patrick; Gagnaire, Beatrice; Renault, Tristan; Osada, M.; Geret, F.; Communal, P. Y.; Jadas-hecart, A.; Gagne, F.. |
In the Atlantic French coast, significant mortalities were observed in oyster communities during gametogenesis. These deaths possibly result from the cumulative effects of various stressors such as seasonal temperature variations, pesticide application and the release of contaminants from the resuspension of sediments. A field survey, based on aquaculture conditions at 15 and 70 cm from the sediment bed with genetically-resistant (R) and -sensitive (S) lines, showed a stress condition. Significant weight loss was observed during May 14th through June 10th for both R and S lines. On one hand, the levels of the egg yolk vitellin in females were decreased at May 14th for both R and S lines. On the other hand, a significant increase in vitellin production was... |
Tipo: Text |
Palavras-chave: Mortalities; Herbicides; Sediment; Biomarkers; Gametogenesis; Crassostrea gigas; Pacific oysters. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3384.pdf |
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Fournier, Jonathan; Levesque, Emmanuelle; Pouvreau, Stephane; Le Pennec, Marcel; Le Moullac, Gilles. |
Pearl culture industry represents one of the dominant business sector of French Polynesia. However, it still entirely relies on unpredictable spat collection success. Our aim was to assess the influence of natural plankton concentration fluctuations on maturation and spawning of the black lip pearl oyster Pinctada margaritifera, during a 4 months survey conducted in Ahe atoll lagoon. Plankton concentration was assessed by chlorophyll a extraction and by microscope counts while gonadic index, gonado-visceral dry weights and histology were used to measure pearl oysters reproduction activity. We found that (i) plankton concentration fluctuations were mainly related to wind regime, (ii) gametogenesis rate was mainly related to plankton concentration, (iii)... |
Tipo: Text |
Palavras-chave: Pearl Oyster; Gametogenesis; Spawning; Phytoplankton; French Polynesia. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00101/21201/19697.pdf |
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Registros recuperados: 41 | |
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