Individual and combined effects of copper and parasitism on osmoregulation in the European eel Anguilla anguilla

• Published in: Aquatic Toxicology
• Main Authors: Lorin-Nebel, Catherine, Felten, Vincent, Blondeau-Bidet, Eva, Grousset, Evelyse, Amilhat, Elsa, Simon, Gael, Biagianti, Sylvie, Charmantier, Guy
• Other Authors: Ecologie des systèmes marins côtiers (Ecosym), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Centre de formation et de recherche sur l'environnement marin (CEFREM), Université de Perpignan Via Domitia (UPVD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité de Recherche Interactions Animal-Environnement - EA 4689 (IAE), Université de Reims Champagne-Ardenne (URCA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: Osmolality; Ionic concentrations; Gills; Na+/K+-ATPase activity; Anguilla anguilla; Anguillicoloides crassus; Copper; [SDE]Environmental Sciences; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; European eel
• Online Access: https://hal.archives-ouvertes.fr/hal-01119341; https://doi.org/10.1016/j.aquatox.2012.11.018

International audience The European eel (Anguilla anguilla), a catadromous species, breeds in the sea and migrates to estuarine, lagoon or freshwater habitats for growth and development. Yellow eels, exposed to low or fluctuating salinities, are also exposed to multiple other stressors as pollution, over-fishing and parasitism, which contribute to the dramatic decrease of eel populations in several European countries. The objective of this study was to evaluate the single and combined effects of waterborne copper and experimental infestation of eels with the nematode Anguillicoloides crassus after a salinity challenge from nearly isotonic (18 ppt) to hypo- (5 ppt) and hypertonic (29 ppt) conditions, in order to investigate the osmoregulatory capacity of eels exposed to these stressors. In a nearly isotonic condition (18 ppt), blood osmolality remained constant over the 6 weeks contamination to Cu2+ and Anguillicoloides crassus. In fish exposed to a salinity challenge of 29 ppt for 2 weeks, no significant effect was recorded in blood osmolality, Na+/K+-ATPase (NKA) activity, Na+ and Cl- concentrations. After 2 weeks at 5 ppt however, a significant blood osmolality decrease was detected in fish exposed to Anguillicoloides crassus infestation with or without Cu2+ addition. This decrease may originate from lower Cl- levels measured in eels exposed to both stressors. Blood Na+ levels remained relatively stable in all tested animals, but gill NKA activities were lower in eels exposed to combined stress. No apparent branchial lesions were detected following the different treatments and immunolocalization of NKA revealed well-differentiated ionocytes. Thus, the 5 ppt challenge in eels exposed to copper and Anguillicoloides crassus seems to clearly enhance iono/osmoregulatory disturbances