Consulta: creatorFacets:"Galois, Robert"
Registros recuperados: 11
Data/hora: 04/06/2024 09:09:26

Dynamics of spatial patterns of microphytobenthic biomass: inferences from a geostatistical analyisis of two comprenhensive surveys in Marennes-Oléron Bay (France)
Provedor de dados: 5
Autores: Guarini, Jean-marc; Blanchard, Gerard; Bacher, Cedric; Gros, Philippe; Riera, Pascal; Richard, Pierre; Gouleau, Dominique; Galois, Robert; Prou, Jean; Sauriau, Pierre-guy.
Microphytobenthos plays an important role as primary producer in shallow embayments subject to a tidal regime. The present paper aims to characterize the spatial patterns of sedimentary chlorophyll a (chl a) biomass in 2 seasons in the wide intertidal mudflats of the Marennes-Oleron Bay (France); furthermore, it provides estimates of total microphytobenthic biomass. Accordingly, a systematic sampling scheme was performed in June 1995 and in January 1996. On average, biomass was higher in June (ca 120 mg chl a m-2) than in January (ca 85 mg chl a m-2). Moreover, the geostatistical analysis revealed that spatial similarities were propagated over larger distances in June (6 km) than in January (2.2 km). In order to account for this result , we suggest that...
Tipo: Text
Palavras-chave: Marennes Oleron; Intertidal mudflat; Geostatistics; Spatial distribution; Chrlorophyll a; Microphytobenthos.
Ano: 1998
URL: https://archimer.ifremer.fr/doc/1998/publication-3820.pdf

Effect of starvation on RNA, DNA and protein-content of laboratory-reared larvae and juveniles of Solea-solea
Provedor de dados: 5
Autores: Richard, P; Bergeron, Jean-pierre; Boulhic, M; Galois, Robert; Person, Jeanine.
Using analyses of individuals, dry weight, RNA, DNA and protein content were measured on the same samples to assess the nutritional status of laboratory-reared larvae and juveniles of Solea solea (L.). During the early life of S. solea, 2 growth periods could be distinguished by dry weight measurements and biochemical composition analysis. After metamorphosis, dry weight, RNA, DNA and protein content per individual increased more slowly than before metamorphosis. RNA, DNA and protein were strongly positively correlated to dry weight of fed larvae. Starvation led to immediate loss of weight and to decrease in RNA and protein content, while DNA amount per individual remained roughly constant. Percentage of protein relative to dry weight was always lower in...
Tipo: Text
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00072/18304/15868.pdf

Temporal changes in lipid condition and parasitic infection by digenean metacercariae of young-of-year common sole Solea solea (L.) in an Atlantic nursery ground (Bay of Biscay, France)
Provedor de dados: 5
Autores: Durieux, Eric; Galois, Robert; Begout, Marie-laure; Sasal, Pierre; Lagardere, Francoise.
Little attention has been paid to flatfish parasitism as a potential factor of variation in year-class strength. The aim of this study was to evaluate the relationship between parasitic infection and nutritional condition of young-of-year (YOY) common sole. Sole were collected monthly from May (early settlement) to November 2004 in a mussel pole culture area, using a push-net or a trawl, and dissected for parasite identification and counts. Total lipids were extracted from the whole body and lipid classes quantified. Triacylglycerols to sterols (free form) ratio (TAG/ST) was used as an index of nutritional status. Digenean metacercariae infection, characterized by two dominant genera, displayed clear seasonal dynamics and the highest records yet reported...
Tipo: Text
Palavras-chave: Nursery; Metacercariae; Parasitism; Lipid condition; YOY; Sole.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2512.PDF

Could a diet enriched with n-3 highly unsaturated fatty acids be considered a promising way to enhance the immune defences and the resistance of Penaeid prawns to environmental stress?
Provedor de dados: 5
Autores: Chim, Liet; Lemaire, Pierrette; Delaporte, Maryse; Le Moullac, Gilles; Galois, Robert; Martin, Jean-louis.
The prawn Penaeus stylirostris (Stimpson), when fed for 28 days with n-3 highly unsaturated fatty acid (HUFA)-enriched feed pellets, demonstrated an enhanced resistance to variations in environmental parameters (a decrease in temperature and salinity over a 4-day period from 28 degreesC to 17 degreesC and from 35 parts per thousand to 10 parts per thousand respectively) and an improvement in their immune defence potential, i.e. increased agglutination titre of plasma and increased respiratory burst of haemocytes.
Tipo: Text
Palavras-chave: Immunostimulation; Osmoregulation; Environment; Stress; Essential fatty acids; Crustaceans.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-606.pdf

Analysis of larval oyster grazing by flow cytometry
Provedor de dados: 5
Autores: Chretiennot-dinet, Marie-josèphe; Vaulot, Daniel; Galois, Robert; Spano, Anna-maria; Robert, Rene.
The ingestion of 8 algal species by oyster larvae (Crassostrea gigas Thunberg, 1793) was measured by flow cytometry (FCM). In a preliminary experiment, cell size (estimated by light scatter) and chlorophyll fluorescence of 30 algal species were evaluated to select those species which could be mixed together and still be easily discriminated by FCM. Grazing experiments were carried out over 48 h with 6 and 15-day old larvae fed on 3 algal mixtures, each containing 3 different algal species. The concentration of each species was estimated at 0, 6, 12, 24 and 48 h by FCM. Grazing pressure on a given algal species was dependent upon the age of the larvae, the time of the day and the composition of the mixture. Grazing rates of older larvae were about twice...
Tipo: Text
Palavras-chave: Oyster larvae; Crassostrea gigas; Grazing; Algae; Selective feeding; Flow cytometry.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00090/20164/17817.pdf

Stable isotopes (delta C-13, delta N-15) and modelling as tools to estimate the trophic ecology of cultivated oysters in two contrasting environments
Provedor de dados: 5
Autores: Leal, J; Dubois, Stanislas; Orvain, Francis; Galois, Robert; Blin, J; Ropert, Michel; Bataille, M; Ourry, A; Lefebvre, S.
Food sources for cultivated marine bivalves generally are not well identified, although they are essential for a better understanding of coastal ecosystems and for the sustainability of shellfish farming activities. In addition to phytoplankton, other organic matter sources (OMS), such as microphytobenthos and detritus (of terrestrial or marine origins), can contribute significantly to the growth of marine bivalves. The aim of this study was to identify the potential food sources and to estimate their contributions to the growth of the Pacific oyster (Crassostrea gigas) in two contrasting trophic environments of Normandy (France): the Baie des Veys (BDV) and the Lingreville area (LIN). Two sites were studied in the BDV area (BDV-S and BDV-N) and one in the...
Tipo: Text
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4621.pdf

Trophic importance of diatoms in an intertidal Zostera noltii seagrass bed: Evidence from stable isotope and fatty acid analyses
Provedor de dados: 5
Autores: Lebreton, Benoit; Richard, Pierre; Galois, Robert; Radenac, Gilles; Pfleger, Camille; Guillou, Gael; Mornet, Francoise; Blanchard, Gerard F.
A current predominant paradigm emphasizes the role of epiphytic algae for invertebrates in most seagrass food webs. However, in some intertidal Zostera noltii beds, epiphyte biomass is very low compared to microphytobenthos and seagrass biomasses. We assessed the role of microphytobenthos in a temperate intertidal Z. noltii bed by combining stable isotope and fatty acid (FA) analyses on primary producers, composite sources suspended particulate organic matter (SPOM) and sediment surface organic matter (SSOM) and the main macrofaunal consumers. Z. noltii showed high delta C-13 (-9.9 parts per thousand) and high 18:2(n-6) and 18:3(n-3) contents. Microphytobenthos was slightly more C-13-depleted (-15.4 parts per thousand) and had high levels of diatom...
Tipo: Text
Palavras-chave: Food web; Intertidal seagrass bed; Microphytobenthos; Zostera noltii; Stable isotope ratio; Fatty acid profiles; European Atlantic coast.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00035/14640/12051.pdf

Effects of water viscosity upon ventilation and metabolism of a flatfish, the common sole Solea solea (L.)
Provedor de dados: 5
Autores: Couturier, Christine; Rouault, Alice; Mckenzie, David; Galois, Robert; Robert, Serge; Joassard, Lucette; Claireaux, Guy.
The French Atlantic coast contains large highly productive intertidal mudflats that are colonised by juveniles of numerous flatfish species, including the common sole (Solea solea, L.). These ecosystems are also heavily exploited by the shellfish farming industry. Intensive bivalve culture is associated with substantial biodeposition (1-6 t-dw ha(-1) day(-1)), which directly or indirectly contributes to increase exopolysaccharide (EPS) concentrations at the interface between water column and seabed. EPS are long-chain molecules organised into colloids, which influence rheological properties of water, particularly viscosity. Increased water viscosity had consequences for ventilatory activity of juvenile flatfish, whereby the minimal pressure required to...
Tipo: Text
Palavras-chave: EPS; Hypoxia; Metabolism; Water viscosity; Biodeposition; Solea solea.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2801.pdf

Cost of Living Dictates what Whales, Dolphins and Porpoises Eat: The Importance of Prey Quality on Predator Foraging Strategies
Provedor de dados: 5
Autores: Spitz, Jerome; Trites, Andrew W.; Becquet, Vanessa; Brind'Amour, Anik; Cherel, Yves; Galois, Robert; Ridoux, Vincent.
Understanding the mechanisms that drive prey selection is a major challenge in foraging ecology. Most studies of foraging strategies have focused on behavioural costs, and have generally failed to recognize that differences in the quality of prey may be as important to predators as the costs of acquisition. Here, we tested whether there is a relationship between the quality of diets (kJ.g(-1)) consumed by cetaceans in the North Atlantic and their metabolic costs of living as estimated by indicators of muscle performance (mitochondrial density, n = 60, and lipid content, n = 37). We found that the cost of living of 11 cetacean species is tightly coupled with the quality of prey they consume. This relationship between diet quality and cost of living appears...
Tipo: Text
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00116/22749/20551.pdf

Influence of oil exposure on the physiology and ecology of the common sole Solea solea: Experimental and field approaches
Provedor de dados: 5
Autores: Claireaux, Guy; Desaunay, Yves; Akcha, Farida; Auperin, Benoît; Bocquene, Gilles; Budzinski, Hélène; Cravedi, Jean-pierre; Davoodi, Fariba; Galois, Robert; Gilliers, Camille; Goanvec, Christelle; Guerault, Daniel; Imbert, Nathalie; Mazeas, Olivier; Nonnotte, Guy; Nonnotte, Liliane; Prunet, Patrick; Sebert, Philippe; Vettier, Aurélie.
Evaluating the ecological impact of an oil spill is a complex issue requiring coherently articulated examination of the sequence of interactions that link the cell, where contaminants exert their effects, to the ecosystem, where interactions with human activities arise. This sequence of interactions traverses the frontiers between scientific disciplines (chemistry, toxicology, physiology, and fisheries ecology). Using the common sole (Solea solea L.) as a model species for the coastal habitats polluted by the "Erika" oil spill, our research project attempted to define indices of functional integrity that characterised the consequences of fuel exposure at the different biological levels. The coupling of field observations with experimental laboratory work...
Tipo: Text
Palavras-chave: Physiological ecology; Common sole; Complex system approach; Oil spill.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-405.pdf

Associations between tissue fatty acid composition and physiological traits of performance and metabolism in the seabass (Dicentrarchus labrax)
Provedor de dados: 5
Autores: Chatelier, Aurelien; Mckenzie, David; Prinet, Aurelie; Galois, Robert; Robin, Jean; Zambonino, Jose-luis; Claireaux, Guy.
Seabass were fed for 4 months with diets where the lipid was provided as either canola oil (CO), palm oil ( PO) or fish oil (FO), to generate diversity in their tissue fatty acid (FA) composition and investigate how this influenced major traits of exercise performance, cardiac performance and respiratory metabolism. In particular, based upon previous observations, we investigated the hypothesis that enriching the fish tissues with oleic and linoleic acids (OA, 18:1n-9 and LA, 18:2n-6, respectively) from the CO and PO diets would improve maximum exercise and cardiac performance, and increase aerobic metabolic scope. This proved to be the case; exercise respirometry on bass fitted with cardiac flow probes revealed that those fed CO and PO diets had a...
Tipo: Text
Palavras-chave: Diet; Fatty acid; Cardiovascular performance; Metabolism; Swimming; Dicentrarchus labrax; Seabass.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1860.pdf