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Trophic cues promote secondary migrations of bivalve recruits in a highly dynamic temperate intertidal system ArchiMer
Foret, Martin; Barbier, Pierrick; Tremblay, Rejean; Meziane, Tarik; Neumeier, Urs; Duvieilbourg, Eric; Olivier, Frederic.
Post-settlement dispersal is a key process in the recruitment of bivalves. To assess the role of such secondary migrations and to identify potential associated triggers, we conducted an in situ sampling survey during the summer recruitment period on the bivalve assemblages of a coarse-sediment temperate tidal habitat in the Chausey archipelago (Normandy, France). The dynamics of drifters were studied using three types of settler traps (for example, bedload, pelagic, and sinking transports), and we monitored both the abiotic (hydrological and hydrodynamic conditions) and the trophic (nano- and pico-sized particulate organic matter [POM]; fatty acid composition of POM and sediment organic matter [SOM]) environmental parameters. Such an approach allows the...
Tipo: Text Palavras-chave: Behavior; Bivalve recruits; Post-settlement dispersal; Secondary migrations; Trophic environment.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00475/58662/62406.pdf
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Impact of arachidonic acid enrichment of live rotifer prey on bacterial communities in rotifer and larval fish cultures ArchiMer
Seychelles, Laurent H.; Doiron, Kim; Audet, Celine; Tremblay, Rejean; Pernet, Fabrice; Lemarchand, Karine.
Rotifers (Brachionus plicatilis), commonly used at first feeding in commercial fish hatcheries, carry a large bacteria load. Because they are relatively poor in essential fatty acids, it is common practice to enrich them with fatty acids, including arachidonic acid (AA). This study aims to determine whether prey enrichment with AA may act as a prebiotic and modify the microbial community composition either in AA-enriched rotifer cultures or in larval-rearing water using winter flounder (Pseudopleuronectes americanus) as a larval fish model. AA enrichment modified the bacterial community composition in both the rotifer culture tanks and the larval-rearing tanks. We observed an increase in the number of cultivable bacteria on TCBS (thiosulfate-citrate-bile...
Tipo: Text Palavras-chave: Communauté bactérienne; Rotifères; Enrichissement en acide arachidonique; Vibrio sp.; Prébiotique; Bacterial community; Rotifers; Arachidonic acid enrichment; Vibrio sp.; Prebiotic.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00137/24778/25189.pdf
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Integrative Study of Physiological Changes Associated with Bacterial Infection in Pacific Oyster Larvae ArchiMer
Genard, Bertrand; Miner, Philippe; Nicolas, Jean-louis; Moraga, Dario; Boudry, Pierre; Pernet, Fabrice; Tremblay, Rejean.
Background: Bacterial infections are common in bivalve larvae and can lead to significant mortality, notably in hatcheries. Numerous studies have identified the pathogenic bacteria involved in such mortalities, but physiological changes associated with pathogen exposure at larval stage are still poorly understood. In the present study, we used an integrative approach including physiological, enzymatic, biochemical, and molecular analyses to investigate changes in energy metabolism, lipid remodelling, cellular stress, and immune status of Crassostrea gigas larvae subjected to experimental infection with the pathogenic bacteria Vibrio coralliilyticus. Findings: Our results showed that V. coralliilyticus exposure induced (1) limited but significant increase...
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Ano: 2013 URL: http://archimer.ifremer.fr/doc/00144/25504/23662.pdf
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Effect of Rhodomonas salina addition to a standard hatchery diet during the early ontogeny of the scallop Pecten maximus ArchiMer
Tremblay, Rejean; Cartier, Simon; Miner, Philippe; Pernet, Fabrice; Quere, Claudie; Moal, Jeanne; Muzellec, Marie-louise; Mazuret, Michel; Samain, Jean-francois.
The main objective of this study was to identify algal diets that maximize the survival and growth and alter the biochemical content of Pecten maximus larvae with the aim of improving metamorphosis. We also evaluated the potential of the cryptophyceae Rhodomonas salina as a food source for these larvae. Two flagellates, Isochrysis aff. galbana (T) and Pavlova lutheri (P), and two diatoms, Chaetoceros gracilis (C) or Skeletonema costatum (S), were tested as two ternary diets, namely PTC and PTS. PTC and PTS were compared with diets that also included R. salina (R). The addition of R. salina and the replacement of C. gracilis by S. costatum in the traditional hatchery diet seem to be two interesting alternatives for increasing the productivity of larval...
Tipo: Text Palavras-chave: Algal fatty acids and sterols; Energetic content; Metamorphosis; Nutrition; Scallop.
Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-2404.pdf
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Trophic environments influence size at metamorphosis and recruitment performance of Pacific oysters ArchiMer
Lagarde, Franck; Richard, Marion; Bec, Beatrice; Roques, Cecile; Mortreux, Serge; Bernard, Ismael; Chiantella, Claude; Messiaen, Gregory; Nadalini, Jean-bruno; Hori, Masakazu; Hamaguchi, Masami; Pouvreau, Stephane; Roque D'Orbcastel, Emmanuelle; Tremblay, Rejean.
Reproduction and recruitment of benthic invertebrates are influenced by the climate and by the ecological structure of marine ecosystems, along with local anthropogenic pressures such as eutrophication or oligotrophication. Using the Pacific oyster Crassostrea gigas as a biological model, we tested the hypothesis that the variability in prodissoconch II (PII) size (i.e. size at metamorphosis) depends on ecological functioning. Settlement and recruitment were assessed at 5 sampling sites on the French Mediterranean shellfish farmed Thau lagoon during the main summer recruitment events in 3 consecutive years (2012-2014). Hydrobiological and planktonic analyses were conducted at 3 sampling sites. Our results showed that recruitment was extremely...
Tipo: Text Palavras-chave: Larval ecology; Recruitment; Prodissoconch II; Crassostrea gigas; Oligotrophication; Cryptophytes; Thau lagoon.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00454/56613/58334.pdf
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Effect of the probiotic strain Phaeobacter gallaeciensis after bacterial challenge on the complete larval development of Pecten maximus ArchiMer
Genard, Bertrand; Larouche, Olivier; Nicolas, Jean-louis; Miner, Philippe; Beaudin, Marie-lou; Tremblay, Rejean.
The aim of this project was to evaluate the impact of probiotic (Phaeobacter gallaeciensis, X34 strain) treatment on the complete development (from veliger to metamorphosis) of Pecten maximus larvae in the context of a bacterial challenge and in conditions more representative of hatchery practices. To that effect, the present study was divided into two main steps. In the first, we used in vitro analyses (antibiograms and microplate assays) to validate the inhibition abilities of X34 on the growth of four Vibrio pathogen species. During the second step, we added pathogens (Vibrio pectenicida) into rearing tanks after two weeks of pre-treatment with the probiotic and then followed the larval development of Pecten maximus through the monitoring of survival...
Tipo: Text Palavras-chave: Probiotics; Hatchery; Bacterial challenge; Larval development; Pecten maximus; Phaeobacter gallaeciensis; Vibrio.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00213/32429/30895.pdf
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Scallop larval survival from erythromycin treated broodstock after conditioning without sediment ArchiMer
Holbach, Marine; Robert, Rene; Boudry, Pierre; Petton, Bruno; Archambault, Philippe; Tremblay, Rejean.
Pathogenic bacteria are known to be one of the main factors affecting Pecten maximus larval survival in hatcheries. As a result, juvenile production often relies on the use of antibiotics during larval culture. However, limitations of the usage of chemicals such as chloramphenicol in aquaculture have been reinforced due to their negative environmental impact and alternatives are accordingly needed. Thus, the importance of bacterial transfer from oocytes to larvae has been studied here as well as procedures to limit larval mortality in P. maximus. In order to reduce bacterial contamination during larval development, we focused on two periods, broodstock conditioning and post-fertilization. The animals were conditioned for 2 months with two erythromycin...
Tipo: Text Palavras-chave: Scallop; Broodstock conditioning; Larval survival; Vibriosis.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00240/35171/33675.pdf
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Temperature effect on survival, growth, and triacylglycerol content during the early ontogeny of Mytilus edulis and M. trossulus ArchiMer
Rayssac, Nathalie; Pernet, Fabrice; Lacasse, Olivia; Tremblay, Rejean.
Temperature is a major factor contributing to the biogeography of intertidal poikilotherms. The population dynamics of intertidal invertebrates like mussels are strongly dependent on larval supply and larval mortality. Unlike adults, which are resistant to fluctuating environmental conditions, larvae are highly sensitive to the physicochemical conditions of the pelagic zone. The effects of rearing temperature on larval and post-larval performance of 2 coexisting mussels species, Mytilus edulis and M. trossulus, were examined in this study. In the first experiment, larvae of both species were reared separately at constant temperatures of 10, 17, and 24 degrees C from D-larvae to the dissoconch stage. In the second experiment, pediveligers were reared under...
Tipo: Text Palavras-chave: Thermal adaptation; Bivalve mollusk; Selection; Biogeography; Lipid; Larval ecology.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00019/13028/10159.pdf
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Shells of the bivalve Astarte moerchi give new evidence of a strong pelagic-benthic coupling shift occurring since the late 1970s in the North Water polynya ArchiMer
Olivier, Frederic; Gaillard, Blandine; Thebault, Julien; Meziane, Tarik; Tremblay, Rejean; Dumont, Dany; Belanger, Simon; Gosselin, Michel; Jolivet, Aurelie; Chauvaud, Laurent; Martel, Andre L.; Rysgaard, Soren; Olivier, Anne-helene; Pettre, Julien; Mars, Jerome; Gerber, Silvain; Archambault, Philippe.
Climate changes in the Arctic may weaken the currently tight pelagic-benthic coupling. In response to decreasing sea ice cover, arctic marine systems are expected to shift from a 'sea-ice algae-benthos' to a 'phytoplankton-zooplankton' dominance. We used mollusc shells as bioarchives and fatty acid trophic markers to estimate the effects of the reduction of sea ice cover on the food exported to the seafloor. Bathyal bivalve Astarte moerchi living at 600m depth in northern Baffin Bay reveals a clear shift in growth variations and Ba/Ca ratios since the late 1970s, which we relate to a change in food availability. Tissue fatty acid compositions show that this species feeds mainly on microalgae exported from the euphotic zone to the seabed. We, therefore,...
Tipo: Text Palavras-chave: Arctic; Climate change; Sclerochronology; Pelagic-benthic coupling; Match; Mismatch hypothesis; Bivalve growth.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00686/79854/82695.pdf
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Effect of shear velocity and flow regimes on scallop post-larval detachment feed on two different diets ArchiMer
Gagne, Renee; Tremblay, Rejean; Olivier, Frederic; Pernet, Fabrice; Miner, Philippe; Samain, Jean-francois.
Through biological flume experiments, we studied the effect of shear velocity and attachment period on the percent detachment of Pecten maximus post-larvae of different sizes reared on two experimental diets. The first diet, (Pavlova lutheri, Isochrysis galbana, Chaetoceros calcitrans), which served as a reference diet (PTC), is commonly used in bivalve hatcheries; the second is the PTC diet with the addition of Rhodomonas salina (PTCR). Our results indicate that the detachment of post-larvae fed PTCR diet showed significant interactions between scallop length, attachment period and shear stress, while the post-larvae feed with the PTC diet showed only effect of shear stress factor. Furthermore, post-larvae exposed to various flume velocities showed...
Tipo: Text Palavras-chave: Attachment; Pecten maximus; Benthic boundary layer; Flume; Diet.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00111/22219/20056.pdf
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Nursery function of coastal temperate benthic habitats: New insight from the bivalve recruitment perspective ArchiMer
Barbier, Pierrick; Meziane, Tarik; Foret, Martin; Tremblay, Rejean; Robert, Rene; Olivier, Frederic.
Marine habitat function has been typically investigated in terms of biogeochemical regulation but rarely in terms of population renewal, which is mainly controlled by recruitment dynamics. The recruitment phase is crucial for organisms with a bentho-pelagic life cycle, such as bivalves, and it regulates the population renewal success. This study provides new insight on the role of temperate benthic habitats on bivalve recruitment, as a function of nursery areas. Six dominant benthic habitats of the Chausey archipelago (Normandy, France) were studied. In each habitat, bivalve recruit assemblages were described at the end of two reproductive seasons. Furthermore, Ostrea edulis juveniles were immerged on each habitat during two months to compare growth...
Tipo: Text Palavras-chave: Benthic habitats; Bivalve recruitment; Nursery function; Ostrea edulis; Fatty acids.
Ano: 2017 URL: http://archimer.ifremer.fr/doc/00367/47863/47845.pdf
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Validation of trophic and anthropic underwater noise as settlement trigger in blue mussels ArchiMer
Jolivet, Aurelie; Tremblay, Rejean; Olivier, Frederic; Gervaise, Cedric; Sonier, Remi; Genard, Betrand; Chauvaud, Laurent.
Like the majority of benthic invertebrates, the blue mussel Mytilus edulis has a bentho-pelagic cycle with its larval settlement being a complex phenomenon involving numerous factors. Among these factors, underwater noise and pelagic trophic conditions have been weakly studied in previous researches. Under laboratory conditions, we tested the hypothesis that picoplankton assimilation by the pediveliger blue mussel larvae acts as a food cue that interacts with anthropic underwater sound to stimulate settlement. We used C-13-labeling microalgae to validate the assimilation of different picoplankton species in the tissues of pediveliger larvae. Our results clearly confirm our hypothesis with a significant synergic effect of these two factors. However, only...
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Ano: 2016 URL: https://archimer.ifremer.fr/doc/00616/72843/72949.pdf
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Match/mismatch between the Mytilus edulis larval supply and seston quality: effect on recruitment ArchiMer
Toupoint, Nicolas; Gilmore-solomon, Lisandre; Bourque, Francois; Myrand, Bruno; Pernet, Fabrice; Olivier, Frederic; Tremblay, Rejean.
We considered Cushing's match/mismatch theory in a heterotrophic environment and hypothesized that settlement and recruitment success in blue mussel are higher when the food supply is rich in polyunsaturated and essential fatty acids (PUFA/EFA). To test this hypothesis, we monitored larval development as well as fatty acid composition in trophic resources during two successive reproductive seasons. The decoupling we found between the presence of competent larvae in the water column and settlement rates strongly suggests that metamorphosis is delayed until conditions are suitable. In both years, the major mussel settlement peak was synchronized with a phytoplanktonic pulse rich in EFA, consisting of a large autotrophic bloom in 2007 and a short but...
Tipo: Text Palavras-chave: Fatty acids; Larval supply; Match/mismatch; Mytilus edulis; Picoeukaryotes; Recruitment; Settlement rate; Trophic settlement trigger.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00098/20923/19676.pdf
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Antimicrobial Compounds from Eukaryotic Microalgae against Human Pathogens and Diseases in Aquaculture ArchiMer
Falaise, Charlotte; Francois, Cyrille; Travers, Marie-agnes; Morga, Benjamin; Haure, Joel; Tremblay, Rejean; Turcotte, Francois; Pasetto, Pamela; Gastineau, Romain; Hardivillier, Yann; Leignel, Vincent; Mouget, Jean-luc.
The search for novel compounds of marine origin has increased in the last decades for their application in various areas such as pharmaceutical, human or animal nutrition, cosmetics or bioenergy. In this context of blue technology development, microalgae are of particular interest due to their immense biodiversity and their relatively simple growth needs. In this review, we discuss about the promising use of microalgae and microalgal compounds as sources of natural antibiotics against human pathogens but also about their potential to limit microbial infections in aquaculture. An alternative to conventional antibiotics is needed as the microbial resistance to these drugs is increasing in humans and animals. Furthermore, using natural antibiotics for...
Tipo: Text Palavras-chave: Biological activity; Antimicrobial; Antibacterial; Antifungal; Antiviral; Biological activity; Haslea; Microalgae; Sustainable aquaculture.
Ano: 2016 URL: http://archimer.ifremer.fr/doc/00349/46052/45719.pdf
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Expression of candidate genes related to metabolism, immunity and cellular stress during massive mortality in the American oyster Crassostrea virginica larvae in relation to biochemical and physiological parameters ArchiMer
Genard, Bertrand; Moraga, Dario; Pernet, Fabrice; David, Elise; Boudry, Pierre; Tremblay, Rejean.
Quantification of mRNA of genes related to metabolism, immunity and cellular stress was examined in relation to a massive mortality event during the culture of American oyster larvae, Crassostrea virginica which was probably, in regard to previous microbiological analysis, induced by vibrio infection. To document molecular changes associated with the mortality event, mRNA levels were compared to biochemical and physiological data, previously described in a companion paper. Among the 18 genes studied, comparatively to the antibiotic control, 10 showed a lower relative gene expression when the massive mortality occurred. Six of them are presumed to be related to metabolism, corroborating the metabolic depression associated with the mortality event suggested...
Tipo: Text Palavras-chave: Massive mortality; Relative gene expression; Metabolism; Immunity; Cellular stress; Larvae.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00075/18585/16138.pdf
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Physiological and biochemical changes associated with massive mortality events occurring in larvae of American oyster (Crassostrea virginica) ArchiMer
Genard, Bertrand; Pernet, Fabrice; Lemarchand, Karine; Boudry, Pierre; Moraga, Dario; Tremblay, Rejean.
In this paper, biochemical and physiological analyses were used to characterize changes associated with mortality event occurred during veliger development of American oyster, Crassostrea virginica. Biochemical analyses included the evaluation of lipid classes, fatty acid composition and total protein content. Larval physiology was evaluated by studying feeding activity, enzymes related to energy metabolism, oxidative stress levels and enzymatic antioxidant defenses. These analyses were complemented by bacterial community analyses as well as by measuring larval oyster performance. We observed that mortality events coincided with (1) strong changes in the surrounding bacterial community; (2) a progressive decrease in feeding activity; (3) higher levels of...
Tipo: Text Palavras-chave: Massive mortality; Larvae; Microbial environment; Lipid; Fatty acids; Energy metabolism; Oxidative stress; Antioxidant enzymes; Crassostrea virginica.
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00051/16231/13753.pdf
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Fecundity, growth rate and survivorship at the interface between two contiguous genetically distinct groups of Semibalanus balanoides ArchiMer
Brind'Amour, Anik; Bourget, Edwin; Tremblay, Rejean.
On the western coast of the Atlantic, according to the literature, 2 distinct groups of Semibalanus balanoides occur with a distinct interface near the Miramichi Estuary, New Brunswick, in the Gulf of St. Lawrence. On each side of this interface, the groups are characterized by clinal variations for MPI (mannose-6-phosphate isomerase) and GPI (glucose-6-phosphate isomerase). The present study was carried out to determine whether selection occurs at this interface, to establish how early in the sessile life period it occurs and to examine the selecting forces involved. Reciprocal transplant experiments of newly settled individuals to both sides of the interface were carried out. No significant differences specifically linked to source or destination were...
Tipo: Text Palavras-chave: Semibalanus; Genetics; Selection; Fecundity; Growth rate; Survival.
Ano: 2002 URL: http://archimer.ifremer.fr/doc/00048/15970/13410.pdf
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Lipid requirements of the scallop Pecten maximus (L.) during larval and post-larval development in relation to addition of Rhodomonas sauna in diet ArchiMer
Gagne, Renee; Tremblay, Rejean; Pernet, Fabrice; Miner, Philippe; Samain, Jean-francois; Olivier, Frederic.
The main objective of this study was to evaluate the effect of the addition of Rhodomonas salina in the diet of Pecten maximus on growth, survival and metamorphosis success in relation to biochemical content. Food quality is an essential factor in the success of larval, post-larval and juvenile development. A diet rich in polyunsaturated fatty acids present an advantage for growth, survival and metamorphosis success. Larvae and post-larvae fed with the diet containing R. sauna showed a higher accumulation of arachidonic acid (20:4n-6) and generally a lower concentration of docosahexaenoic acid (22:6n-3). Addition of R. sauna in diet was related with higher level of eicosapentaenoic acid (20:5n-3) in larval stages, but lower level in post-larvae. Addition...
Tipo: Text Palavras-chave: Nutrition; Biochemical characteristics; Fatty acids; Sterol profiles.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00019/13045/10205.pdf
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Physiological and biochemical indicators of mussel seed quality in relation to temperatures ArchiMer
Tremblay, Rejean; Landry, Thomas; Leblanc, Neil; Pernet, Fabrice; Barkhouse, Carla; Sevigny, Jean-marie.
The bivalve's aquaculture industry is an important component of the economy in Eastern Canada. Seed collection is an initial and critical activity in most bivalve aquaculture industries including mussel farming in Prince Edward Island, production is entirely dependent on natural spat collection. Although seed supply is not a concern from a quantitative standpoint, there are growing concerns about the quality of natural seed. The general objective of this study was to identify and assess mussel seed quality criteria on the basis of physiological and biochemical status under laboratory and field conditions. The performance, as estimated by metabolic measurements, lipid class composition, multi-locus heterozygosity (MLH) and survival to stressful environment...
Tipo: Text Palavras-chave: Wild seed; Aquaculture; Physiological fitness; Growth; Survival; Multi-locus heterozygosity; Mytilus spp..
Ano: 2011 URL: http://archimer.ifremer.fr/doc/00051/16232/13754.pdf
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Effects of hydrodynamic factors on Pecten maximus larval development ArchiMer
Holbach, Marine; Robert, Rene; Miner, Philippe; Mingant, Christian; Boudry, Pierre; Tremblay, Rejean.
Hatchery production of great scallop, Pecten maximus, remains unpredictable, notably due to poor larval survival. Large-scale flow-through systems up to 3500 L have been developed to avoid the use of antibiotics in static systems. Alternatively, small-scale flow-through systems have been successfully applied for oysters but they proved to be unsuitable to rear scallop larvae. By focusing on physical factors presumed to limit P. maximus larval development, this study aimed to optimize great scallop larvae rearing parameters under controlled conditions. First, the influence of aeration on larval performances, energetic metabolism and antioxidant defences were studied both in static and flow-through systems. Aeration depressed larval food intake, regardless...
Tipo: Text Palavras-chave: Aeration; Flow-through; Larval physiology; Pecten maximus.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00384/49508/51151.pdf
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