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Sami Souissi - One of the best experts on this subject based on the ideXlab platform.
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Complete mitochondrial genome of the calanoid copepod Eurytemora affinis (Calanoida, Temoridae)
Mitochondrial DNA Part B, 2019Co-Authors: Beom-soon Choi, Jeonghoon Han, Dae-sik Hwang, Sami Souissi, Atsushi Hagiwara, Jae-seong LeeAbstract:The complete mitochondrial genome was sequenced from the calanoid copepod Eurytemora affinis. The sequenced total genome size was 18,553 bp. The mitochondrial genome of E. affinis has 13 protein-co...
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Population response of the estuarine copepod Eurytemora affinis to its bioaccumulation of trace metals
Chemosphere, 2019Co-Authors: Mahammed Zidour, Zakia Boubechiche, Yen-ju Pan, Capucine Bialais, Benoit Cudennec, Thierry Grard, Djamel Drider, Christophe Flahaut, Baghdad Ouddane, Sami SouissiAbstract:Abstract We evaluated the acute toxicities of metals cadmium (Cd), copper (Cu) and nickel (Ni) to a widely-distributed copepod Eurytemora affinis isolated from the Seine estuary. Both sexes of adult E. affinis were exposed separately to the three metals at concentration gradients to determine its 50% lethal concentration (LC50). After 4 days of exposure, both males and females showed a higher sensitivity to Cu (male LC50: 25.0 μg.L−1 and female LC50: 38.0 μg.L−1) than to Ni (male LC50: 90.0 μg.L−1 and female 161.0 μg.L−1) and Cd (male LC50: 127.8 μg.L−1 and female LC50: 90.0 μg.L−1). To assess for the first time, the extend of metal bioaccumulation and its effect at population scale, late stages (>200 μm) were collected and exposed to each metal at the concentration of 1/3 LC50, and to their mixture during 144 h without feeding. The Cd concentration consistently increased with time until the end of the experiment, whereas the Ni and Cu concentrations reached a plateau after 24 h and 72 h exposure, respectively. The results revealed that the copepods could accumulate Cu faster than Ni and Cd either in the treatment alone (0.58 L g−1.d−1) or in the three-metal mixture (0.72 L g−1.d−1) after 50% of exposure time (72 h). The number of individuals decreased in copepod populations except for the Cd treatment, where the number of nauplii increased. In addition, all treatments of metal exposure negatively affected bacterial densities in the copepod cultures, where the Cu treatment showed a negative remarkable effect compared with Cd and Ni treatment did.
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physiological improvement in the copepod Eurytemora affinis through thermal and multi generational selection
Aquaculture Research, 2016Co-Authors: Anissa Souissi, Sami Souissi, Benni Winding HansenAbstract:As a major part of fish larval diet in nature, copepods constitute an appropriate live prey for aquaculture purposes. Considering the difficulty of mastering copepod mass production, studies on their growth performance at different environmental conditions are needed to improve their productivity. In this study a new selective approach based on temperature control is proposed to improve the physiological (body size, fecundity and lipid storage) performance of copepods. The estuarine copepod Eurytemora affinis known to have a high genetic variance in temperature tolerance was used as a biological model. First two different copepod lines were obtained after long-term culture at constant cold (7°C) and warm (20°C) temperatures. Then both populations were transferred to a higher temperature of 24°C appropriate for aquaculture use and followed during five generations. During the first two generations (F1–F2) of a cold-acclimated population, female body size and fecundity decreased significantly whereas the survival rate remained high. The high lipid content of this population was used by females to compensate the heat shock of more than 10°C. However, the survival rate decreased dramatically in F3 but allowed the selection of robust individuals which progressively improved their fitness during the following generations. So, compared to the warm acclimated population, the cold acclimated one showed larger body size, higher fecundity and better lipid storage. After only five generations at 24°C the cold-acclimated population showed a significant genetic gain in prosome length compared to the warm acclimated one.
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Differential protein expression in the estuarine copepod Eurytemora affinis after diuron and alkylphenol exposures.
Environmental Toxicology and Chemistry, 2016Co-Authors: Céline Boulangé-lecomte, Sami Souissi, Elena Legrand, Kévin Cailleaud, Hélène Budzinski, Béatrice Rocher, Pascal Cosette, David Devreker, Joëlle Forget-lerayAbstract:Proteomics was used in the calanoid copepod Eurytemora affinis for screening of protein expression modifications induced by organic contaminants. The copepods were exposed in a continuous flow-through system for 86 h to environmentally relevant concentrations of contaminants representative of the pollution in the Seine Estuary (Haute-Normandie, France; diuron, 500 ng L(-1) ; alkylphenol mixture, 1000 ng L(-1) ). Proteome analysis of whole-body copepod extracts by 2-dimensional gel electrophoresis revealed that the contaminants induced modifications in protein expression, with the highest quantitative variations occurring after diuron exposure. Specifically, 88 and 41 proteins were differentially expressed after diuron and alkylphenol treatments, respectively. After mass spectrometry analysis, 51 (diuron exposure) and 15 (alkylphenol exposure) proteins were identified. The identified proteins were potentially related to energy metabolism, cell growth, nervous signal conductivity, excitotoxicity, oxidative stress response, and antioxidant defense. The data suggest a massive general disturbance of physiological functions of E. affinis after diuron exposure, whereas alkylphenols induced an alteration of a few targeted physiological functions. The protein expression signatures identified after contaminant exposure deserve further investigation in terms of the development of novel potential biomarkers for water quality assessment. Environ Toxicol Chem 2016;35:1860-1871. © 2015 SETAC.
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Evaluation of the Copepod Eurytemora affinis Life History Response to Temperature and Salinity Increases.
Zoological studies, 2016Co-Authors: Anissa Souissi, Sami Souissi, Jiang-shiou HwangAbstract:Anissa Souissi, Sami Souissi, and Jiang-Shiou Hwang (2016) Zooplankton and particularly copepods have a key role in the functioning of aquatic ecosystems. However, the mechanisms involved in the physiological responses of copepods to temperature and salinity increases are little understood, and the role of plasticity involved in facing environmental changes has rarely been demonstrated experimentally. In this study, the copepod Eurytemora affinis, widely distributed in the northern hemisphere, was selected as a biological model to test the effect of a 4°C temperature increase at two salinities. In addition to the optimal salinity (15 psu), a stressful condition of salinity 25 psu was also verified. Copepods from the Seine estuary were acclimated in laboratory to their optimal temperature of 15°C at salinity 15 PSU and then they were acclimated during several generations to their upper thermal limit (20°C) at two salinities (15 and 25 PSU), after which the temperature was raised by 4°C. This experiment revealed that after long-term acclimation and under unlimited food conditions, E. affinis maintained good fitness at 20°C and at both optimal and stressful salinities. After temperature increase to 24°C, the population remained viable but copepod size was significantly decreased as well as female's fecundity. The decrease of fitness was accentuated under the additional stressful condition of salinity 25 psu. This study demonstrated that the mechanisms of response to temperature and salinity increases (i.e. global warming) are complex, and should be investigated through experimental studies that consider acclimation and multigenerational factors. Our results will enrich the development of Individual-Based Models (IBMs) capable to test the role of microevolution and plasticity of E. affinis in the framework of future climate scenarios.
N. Toumi - One of the best experts on this subject based on the ideXlab platform.
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Spatial spring distribution of the copepod Eurytemora affinis (Copepoda,Calanoida) in a restoring estuary, the Scheldt (Belgium)
Estuarine Coastal and Shelf Science, 2010Co-Authors: Benoit Mialet, Stefan Van Damme, Frédéric Azémar, Tom Maris, C. Sossou, P Ruiz, M. Lionard, Antoine Lecerf, Koenraad Muylaert, N. ToumiAbstract:The spatial spring distribution of Eurytemora affinis (adults and C5) in the Scheldt estuary (Belgium) brackish and freshwater reacheswas studied in between 1996 and 2007. The bulk of the E. affinis population being generally situated in the brackish water reach (salinity > 0.5); we studied which environmental factors are responsible for its recent sporadic occurrence in the freshwater estuarine reach. Using PLS analysis, it is shown that its presence upstream is limited by a sufficient oxygen concentration (>4mg l-1) that is associated with temperature. Not only are the environmental conditions in the upstream zone important, but also the frequent presence of an O2 minimum zone in the mid-estuary (O2 min < 1.3mg l-1) seems to block the movement of the downstream E. affinis population in an upstream direction. Occasionally, the bulk of the population is however situated upstream. During these periods, high E. affinis abundancewas also observed in the Durme tributary. Our findings suggest the possibility to use E. affinis as an "indicator" species ofwaterquality, but also lead us to stress the necessity to consider conditions over the entire estuary when studying restoration effects, not exclusively in the zone of interest.
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Spatial spring distribution of the copepod Eurytemora affinis (Copepoda, Calanoida) in a restoring estuary, the Scheldt (Belgium)
Estuarine Coastal and Shelf Science, 2010Co-Authors: Benoit Mialet, Frédéric Azémar, Tom Maris, C. Sossou, P Ruiz, M. Lionard, S. Van Damme, Antoine Lecerf, Koenraad Muylaert, N. ToumiAbstract:Abstract The spatial spring distribution of Eurytemora affinis (adults and C5) in the Scheldt estuary (Belgium) brackish and freshwater reaches was studied in between 1996 and 2007. The bulk of the E. affinis population being generally situated in the brackish water reach (salinity > 0.5); we studied which environmental factors are responsible for its recent sporadic occurrence in the freshwater estuarine reach. Using PLS analysis, it is shown that its presence upstream is limited by a sufficient oxygen concentration (>4 mg l−1) that is associated with temperature. Not only are the environmental conditions in the upstream zone important, but also the frequent presence of an O2 minimum zone in the mid-estuary (O2 min
Reinhard Heerkloss - One of the best experts on this subject based on the ideXlab platform.
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does Eurytemora affinis copepoda control the population growth of keratella cochlearis rotifera in the brackish water dars zingst lagoon southern baltic sea
Journal of Plankton Research, 2009Co-Authors: Martin Feike, Reinhard HeerklossAbstract:Laboratory experiments and long-term zooplankton monitoring data suggest a possible suppression of the population growth of the rotifer Keratella cochlearis f. tecta by predation by the copepod Eurytemora affinis.
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Does Eurytemora affinis (Copepoda) control the population growth of Keratella cochlearis (Rotifera) in the brackish water Darß–Zingst Lagoon (southern Baltic Sea)?
Journal of Plankton Research, 2009Co-Authors: Martin Feike, Reinhard HeerklossAbstract:Laboratory experiments and long-term zooplankton monitoring data suggest a possible suppression of the population growth of the rotifer Keratella cochlearis f. tecta by predation by the copepod Eurytemora affinis.
Stefan Van Damme - One of the best experts on this subject based on the ideXlab platform.
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Spatial spring distribution of the copepod Eurytemora affinis (Copepoda,Calanoida) in a restoring estuary, the Scheldt (Belgium)
Estuarine Coastal and Shelf Science, 2010Co-Authors: Benoit Mialet, Stefan Van Damme, Frédéric Azémar, Tom Maris, C. Sossou, P Ruiz, M. Lionard, Antoine Lecerf, Koenraad Muylaert, N. ToumiAbstract:The spatial spring distribution of Eurytemora affinis (adults and C5) in the Scheldt estuary (Belgium) brackish and freshwater reacheswas studied in between 1996 and 2007. The bulk of the E. affinis population being generally situated in the brackish water reach (salinity > 0.5); we studied which environmental factors are responsible for its recent sporadic occurrence in the freshwater estuarine reach. Using PLS analysis, it is shown that its presence upstream is limited by a sufficient oxygen concentration (>4mg l-1) that is associated with temperature. Not only are the environmental conditions in the upstream zone important, but also the frequent presence of an O2 minimum zone in the mid-estuary (O2 min < 1.3mg l-1) seems to block the movement of the downstream E. affinis population in an upstream direction. Occasionally, the bulk of the population is however situated upstream. During these periods, high E. affinis abundancewas also observed in the Durme tributary. Our findings suggest the possibility to use E. affinis as an "indicator" species ofwaterquality, but also lead us to stress the necessity to consider conditions over the entire estuary when studying restoration effects, not exclusively in the zone of interest.
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zooplankton in the schelde estuary belgium the netherlands the distribution of Eurytemora affinis effect of oxygen
Journal of Plankton Research, 2003Co-Authors: Ward Appeltans, A Hannouti, Stefan Van Damme, Karline Soetaert, Rik Vanthomme, M TackxAbstract:During the 1990s, a spatial shift of the population of Eurytemora affinis (Copepoda, Calanoida) from brackish water towards lower salinities in the Schelde estuary coincided with an increase in oxygen concentration in the freshwater zone. Other ecological and hydrodynamic factors potentially influencing the spatial distribution of the species did not change significantly in either zone, which suggests that the E. affinis population actively responded to the change in oxygen concentration.
Benoit Mialet - One of the best experts on this subject based on the ideXlab platform.
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Spatial spring distribution of the copepod Eurytemora affinis (Copepoda,Calanoida) in a restoring estuary, the Scheldt (Belgium)
Estuarine Coastal and Shelf Science, 2010Co-Authors: Benoit Mialet, Stefan Van Damme, Frédéric Azémar, Tom Maris, C. Sossou, P Ruiz, M. Lionard, Antoine Lecerf, Koenraad Muylaert, N. ToumiAbstract:The spatial spring distribution of Eurytemora affinis (adults and C5) in the Scheldt estuary (Belgium) brackish and freshwater reacheswas studied in between 1996 and 2007. The bulk of the E. affinis population being generally situated in the brackish water reach (salinity > 0.5); we studied which environmental factors are responsible for its recent sporadic occurrence in the freshwater estuarine reach. Using PLS analysis, it is shown that its presence upstream is limited by a sufficient oxygen concentration (>4mg l-1) that is associated with temperature. Not only are the environmental conditions in the upstream zone important, but also the frequent presence of an O2 minimum zone in the mid-estuary (O2 min < 1.3mg l-1) seems to block the movement of the downstream E. affinis population in an upstream direction. Occasionally, the bulk of the population is however situated upstream. During these periods, high E. affinis abundancewas also observed in the Durme tributary. Our findings suggest the possibility to use E. affinis as an "indicator" species ofwaterquality, but also lead us to stress the necessity to consider conditions over the entire estuary when studying restoration effects, not exclusively in the zone of interest.
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Spatial spring distribution of the copepod Eurytemora affinis (Copepoda, Calanoida) in a restoring estuary, the Scheldt (Belgium)
Estuarine Coastal and Shelf Science, 2010Co-Authors: Benoit Mialet, Frédéric Azémar, Tom Maris, C. Sossou, P Ruiz, M. Lionard, S. Van Damme, Antoine Lecerf, Koenraad Muylaert, N. ToumiAbstract:Abstract The spatial spring distribution of Eurytemora affinis (adults and C5) in the Scheldt estuary (Belgium) brackish and freshwater reaches was studied in between 1996 and 2007. The bulk of the E. affinis population being generally situated in the brackish water reach (salinity > 0.5); we studied which environmental factors are responsible for its recent sporadic occurrence in the freshwater estuarine reach. Using PLS analysis, it is shown that its presence upstream is limited by a sufficient oxygen concentration (>4 mg l−1) that is associated with temperature. Not only are the environmental conditions in the upstream zone important, but also the frequent presence of an O2 minimum zone in the mid-estuary (O2 min
