Consulta: creatorFacets:"Gaertner-mazouni, Nabila"
Registros recuperados: 15
Data/hora: 01/06/2024 03:34:51

Gonad transcriptome analysis of pearl oyster Pinctada margaritifera: identification of potential sex differentiation and sex determining genes
Provedor de dados: 5
Autores: 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

Identifying Robust Proxies of Gonad Maturation for the Protandrous Hermaphrodite     Tridacna maxima     (Röding, 1798, Bivalvia) from Individual to Population Scale
Provedor de dados: 5
Autores: Menoud, Mathilde; Van Wynsberge, Simon; Le Moullac, Gilles; Levy, Peva; Andrefouet, Serge; Remoissenet, Georges; Gaertner-mazouni, Nabila.
Monitoring gonadmaturation for protandrous and functional hermaphrodite species such as the giant clamTridacna maxima is difficult due to the juxtaposition and relative proportion ofmale and female tissues in the gonad [gonadal sex ratio (GSR)]. Here, the relevance of the widely used gonadosomatic index (GSI) as proxy of giant clam gonad maturation is tested with a large dataset (n = 265). Gonadosomatic index is compared with other indices, namely the proportion of the male part harboring spermatozoids, the proportion of empty oocyte follicles, the mean oocyte diameter, and the oocyte elongation. At gonad scale, high index variability highlighted partial spawning. At individual scale, male and female maturation proxies were contrasted, showing either...
Tipo: Text
Palavras-chave: Giant clam; Marine bivalve; Reproduction; Spawn; Tatakoto atoll; Histology; Tridacna maxima.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00333/44441/44111.pdf

Considering reefscape configuration and composition in biophysical models advance seascape genetics
Provedor de dados: 5
Autores: Van Wynsberge, Simon; Andrefouet, Serge; Gaertner-mazouni, Nabila; Tiavouane, Josina; Grulois, Daphne; Lefevre, Jerome; Pinsky, Malin L.; Fauvelot, Cecile.
Previous seascape genetics studies have emphasized the role of ocean currents and geographic distances to explain the genetic structure of marine species, but the role of benthic habitat has been more rarely considered. Here, we compared the population genetic structure observed in West Pacific giant clam populations against model simulations that accounted habitat composition and configuration, geographical distance, and oceanic currents. Dispersal determined by geographical distance provided a modelled genetic structure in better agreement with the observations than dispersal by oceanic currents, possibly due to insufficient spatial resolution of available oceanographic and coastal circulation models. Considering both habitat composition and...
Tipo: Text
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00387/49791/50345.pdf

Influence of water temperature and food on the last stages of cultured pearl mineralization from the black-lip pearl oyster Pinctada margaritifera
Provedor de dados: 5
Autores: Latchere, Oihana; Mehn, Vincent; Gaertner-mazouni, Nabila; Le Moullac, Gilles; Fievet, Julie; Belliard, Corinne; Cabral, Philippe; Saulnier, Denis.
Environmental parameters, such as food level and water temperature, have been shown to be major factors influencing pearl oyster shell growth and molecular mechanisms involved in this biomineralization process. The present study investigates the effect of food level (i.e., microalgal concentration) and water temperature, in laboratory controlled conditions, on the last stages of pearl mineralization in order to assess their impact on pearl quality. To this end, grafted pearl oysters were fed at different levels of food and subjected to different water temperatures one month prior to harvest to evaluate the effect of these factors on 1) pearl and shell deposition rate, 2) expression of genes involved in biomineralization in pearl sacs, 3) nacre...
Tipo: Text
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00428/54007/55223.pdf

Le Réseau de Suivi Lagunaire : un outil de diagnostic et d’aide à l’action pour la lutte contre l’eutrophisation des lagunes. Une stratégie d’information et de transfert aux acteurs.
Provedor de dados: 5
Autores: Daloz, Aurélien; Gaertner-mazouni, Nabila; Barral, Marc; Malet, Nathalie; Moragues, Laurent; Fiandrino, Annie; Laugier, Thierry; Derolez, Valerie; Munaron, Dominique.
Le RSL véritable outil de veille et d’aide à la décision, produit chaque année un diagnostic des lagunes de la Région Languedoc-Roussillon vis-à-vis de l’eutrophisation.Il permet ainsi d’alimenter les réflexions dans le cadre des démarches de gestion concertée, d’orienter la mise en œuvre d’action et les travaux de restauration prioritaires.
Tipo: Text
Ano: 2009
URL: http://archimer.ifremer.fr/doc/00008/11946/8652.pdf

Effect of temperature, food availability, and estradiol injection on gametogenesis and gender in the pearl oyster     Pinctada margaritifera
Provedor de dados: 5
Autores: Teaniniuraitemoana, Vaihiti; Lepretre, Maxime; Levy, Peva; Vanaa, Vincent; Parrad, Sophie; Gaertner-mazouni, Nabila; Gueguen, Yannick; Huvet, Arnaud; Le Moullac, Gilles.
The black-lip pearl oyster Pinctada margaritifera is a protandrous hermaphrodite species. Its economic value has led to the development of controlled hatchery reproduction techniques, although many aspects remain to be optimized. In order to understand reproductive mechanisms and their controlling factors, two independent experiments were designed to test hypotheses of gametogenesis and sex ratio control by environmental and hormonal factors. In one, pearl oysters were exposed under controlled conditions at different combinations of temperature (24 and 28°C) and food level (10,000 and 40,000 cells mL−1); whereas in the other, pearl oysters were conditioned under natural conditions into the lagoon and subjected to successive 17β-estradiol injections (100 μg...
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00285/39638/38184.pdf

Influence of preoperative food and temperature conditions on pearl biogenesis in Pinctada margaritifera
Provedor de dados: 5
Autores: Latchere, Oihana; Le Moullac, Gilles; Gaertner-mazouni, Nabila; Fievet, Julie; Magre, Kevin; Saulnier, Denis.
Trophic conditions and water temperature strongly influence bivalve physiological processes and metabolism. In black-lip pearl oyster Pinctada margaritifera, these parameters have been shown to affect shell biomineralization. The present study investigated the effect of preoperative food level (i.e., microalgal concentration) and temperature on pearl biomineralization. Donor and recipient oysters were conditioned at different levels of food and temperature during the preoperative phase to evaluate the influence of these factors on 1) pearl retention rate (grafting success), 2) expression of genes involved in biomineralization in the mantle and pearl sac and 3) pearl quality traits. Our study confirmed the influence of both microalgal concentration and...
Tipo: Text
Palavras-chave: Pinctada margaritifera; Cultured pearl; Biomineralization; Environment; Gene expression; Pearl quality.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00387/49799/50367.pdf

Growth, Survival and Reproduction of the Giant Clam Tridacna maxima (Röding 1798, Bivalvia) in Two Contrasting Lagoons in French Polynesia
Provedor de dados: 5
Autores: Van Wynsberge, Simon; Andrefouet, Serge; Gaertner-mazouni, Nabila; Wabnitz, Colette C. C.; Menoud, Mathilde; Le Moullac, Gilles; Levy, Peva; Gilbert, Antoine; Remoissenet, Georges.
Shell growth, reproduction, and natural mortality of the giant clam Tridacna maxima were characterized over a two-year-period in the lagoon of the high island of Tubuai (Austral Archipelago) and in the semi-closed lagoon of Tatakoto (Tuamotu Archipelago) in French Polynesia. We also recorded temperature, water level, tidal slope, tidal range, and mean wave height in both lagoons. Lower lagoon aperture and exposure to oceanic swells at Tatakoto than at Tubuai was responsible for lower lagoon water renewal, as well as higher variability in temperature and water level at Tatakoto across the studied period. These different environmental conditions had an impact on giant clams. Firstly, spawning events in the lagoon of Tatakoto, detected by gonad maturity...
Tipo: Text
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00371/48214/48335.pdf

Molecular Signatures Discriminating the Male and the Female Sexual Pathways in the Pearl Oyster Pinctada margaritifera
Provedor de dados: 5
Autores: Teaniniuraitemoana, Vaihiti; Huvet, Arnaud; Levy, Peva; Gaertner-mazouni, Nabila; Gueguen, Yannick; Le Moullac, Gilles.
The genomics of economically important marine bivalves is studied to provide better understanding of the molecular mechanisms underlying their different reproductive strategies. The recently available gonad transcriptome of the black-lip pearl oyster Pinctada margaritifera is a novel and powerful resource to study these mechanisms in marine mollusks displaying hermaphroditic features. In this study, RNAseq quantification data of the P. margaritifera gonad transcriptome were analyzed to identify candidate genes in histologically-characterized gonad samples to provide molecular signatures of the female and male sexual pathway in this pearl oyster. Based on the RNAseq data set, stringent expression analysis identified 1,937 contigs that were differentially...
Tipo: Text
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00256/36768/35374.pdf

Influence of farmed pearl oysters and associated biofouling communities on nutrient regeneration in lagoons of French Polynesia
Provedor de dados: 5
Autores: Lacoste, Elise; Gueguen, Yannick; Le Moullac, Gilles; Koua, Manaarii Sham; Gaertner-mazouni, Nabila.
Bivalve cultivation can significantly contribute to nutrient cycling in semi-enclosed ecosystems. We investigated the influence of suspended pearl oyster culture on nutrient regeneration in the water column of 3 oligotrophic lagoons in French Polynesia. The aim of this first study performed in a tropical area was to assess the seasonal variability of nutrient fluxes and to quantify the contribution of biofouling communities. In situ metabolic enclosure systems were used to measure nutrient uptake or release by ‘cultivation units’ (i.e. 4 pearl oysters with or without associated biofouling). In all 3 study lagoons (Tahiti, Mangareva, Ahe), nutrient fluxes produced by pearl oyster and associated biofouling communities (CR units) were 4- to 6-fold higher than...
Tipo: Text
Palavras-chave: Pearl oysters; Biofouling; Nutrient flux; Aquaculture impact.
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00201/31193/29592.pdf

Integrated management of pearl culture in French Polynesia in the context of global change: Synopsis of existing results
Provedor de dados: 5
Autores: Gueguen, Yannick; Gaertner-mazouni, Nabila; Lo, Cedrik; Le Moullac, Gilles.
The paper presents a state of the art on knowledge of the black pearl oyster aquaculture at the scale of French Polynesia. It also introduces the main results obtained throughout the multi-partners POLYPERL project. The goal of this project was to develop an integrated and participative action-research of the pearl oyster culture system, focusing on the environmental, technological, economical and societal dimensions impacting the industry. The research proposed ranges from the understanding of biological phenomena of the production system to socio-economic aspects and governance of the industry, taking into account the management of anthropogenic, climate and health risks. We introduce here the different papers from the POLYPERL project that are compiled...
Tipo: Text
Palavras-chave: Pearl culture; Global change; French Polynesia; Pinctada margaritifera.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00346/45698/45320.pdf

Biofouling development and its effect on growth and reproduction of the farmed pearl oyster Pinctada margaritifera
Provedor de dados: 5
Autores: Lacoste, Elise; Le Moullac, Gilles; Levy, Peva; Gueguen, Yannick; Gaertner-mazouni, Nabila.
In bivalve aquaculture, dominant fouling organisms are filter feeders which can compete for food with reared bivalves, sometimes causing mortality or reducing their growth rate. This study investigated the effect of biofouling on the farmed pearl oyster Pinctada margaritifera in two lagoons of French Polynesia. Survival, growth and reproduction of 2 year-old pearl oysters were monitored with regular sampling schedules, from the initial stage of colonization up to 20 months of biofouling accumulation. Control groups of pearl oysters were kept free of biofouling as is the current practice in pearl farms. After more than a year of monitoring, no significant difference was recorded in shell growth rate between pearl oysters reared with epibionts and the...
Tipo: Text
Palavras-chave: Pearl oyster culture; Pinctada margaritifera; Biofouling; Growth; Reproduction.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00201/31188/29587.pdf

Trophic relationships between the farmed pearl oyster Pinctada margaritifera and its epibionts revealed by stable isotopes and feeding experiments
Provedor de dados: 5
Autores: Lacoste, Elise; Raimbault, Patrick; Harmelin-vivien, Mireille; Gaertner-mazouni, Nabila.
Bivalve cultures support a host of epibionts, mainly suspension feeders, which can compete for food resources with the cultivated bivalves. However, the magnitude of interspecific competition for food in bivalve aquaculture settings remains inconclusive, especially in tropical areas. We investigated the interactions for food between the farmed pearl oyster Pinctada margaritifera and its epibionts, using stable isotope analysis and feeding experiments. Inter-and intraspecific variations of delta C-13 and delta N-15 stable isotope ratios (SIRs) were determined for oysters in the presence or absence of epibionts. The diet of the most abundant epibionts, Herdmania momus and Didemnum sp., was specified using isotope measurements and flow cytometry during...
Tipo: Text
Palavras-chave: Ascidian; Biofouling; Trophic interactions; Stable isotope; Flow cytometry.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00664/77582/79564.pdf

Evidence of the bioaccumulation of ciguatoxins in giant clams (Tridacna maxima) exposed to Gambierdiscus spp. cells
Provedor de dados: 5
Autores: Roue, Melanie; Darius, Helene Taiana; Picot, Sandy; Ung, Andre; Viallon, Jerome; Gaertner-mazouni, Nabila; Sibat, Manoella; Amzil, Zouher; Chinain, Mireille.
Ciguatera Fish Poisoning (CFP) is a foodborne disease classically related to the consumption of tropical coral reef fishes contaminated with ciguatoxins (CTXs), neurotoxins produced by dinoflagellates of the Gambierdiscus genus. Severe atypical ciguatera-like incidents involving giant clams, a marine resource highly consumed in the South Pacific, are also frequently reported in many Pacific Islands Countries and Territories. The present study was designed to assess the ability of giant clams to accumulate CTXs in their tissues and highlight the potential health risks associated with their consumption. Since giant clams are likely to be exposed to both free-swimming Gambierdiscus cells and dissolved CTXs in natural environment, ex situ contamination...
Tipo: Text
Palavras-chave: Giant clams; Ex situ contamination; Ciguatoxins; Gambierdiscus polynesiensis; LC-MS/MS; Neuroblastoma cell-based assay.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00343/45415/45123.pdf

Is sustainable development a motor or a constraint for the professionalization of the pearl oyster industry in tahiti?
Provedor de dados: 5
Autores: Rey-valette, Helene; Lacoste, Elise; Perez, Jose; Raux, Pascal; Gaertner, Jean-claude; Gaertner-mazouni, Nabila.
This article reports the results of a survey of the pearl oyster industry in French Polynesia territory. Its purpose is to examine the perceptions of the priorities for the development of this industry towards sustainable development. These perceptions were apprehended by a survey of pearl oyster farmers and other stakeholders of the sector (management authorities, scientists). After describing the methodological protocol of these investigations, it comes to confront the priorities chosen by professionals (i.e. pearl farmers) concerning sustainable development, with the perceptions of others stakeholders in the sector. Secondly it comes to build a typology of the priorities of pearl farmers concerning sustainable development. This analysis enables the...
Tipo: Text
Palavras-chave: Sustainable development; Pearl oyster farming; Perceptions; Collective learning process; Indicators; French Polynesia.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00288/39918/38479.pdf