Event Abstract Back to Event Short report on the ectoparasitic fauna from a wild Epinephelus marginatus and osmotic shock efficiency on their removal Alfredo M. Rodrigues1, Luís M. Silva1, Sílvia C. Gonçalves2, 3*, João P. Correia1, 2, Rui M. Rosa1 and Nina S. Vieira1 1 Flying Sharks, Portugal 2 MARE - Marine and Environmental Sciences Centre, School of Tourism and Maritime Technology, Polytechnic Institute of Leiria, Portugal 3 MARE – Marine and Environmental Sciences Centre, Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Portugal The Caligidae family is one of the main crustacean parasitic groups affecting groupers and dusky groupers. Those ectoparasites usually feed on the hosts epidermal tissue, mucus and blood, being a severe pathogen for some fish. The freshwater dip or osmotic shock, is commonly used to remove known parasites, like Cryptocaryon irritans, from fish hosts, and it’s usually effective against external trematodes, protozoan parasites and ectoparasites. This method works for most ectoparasites, as they lack efficient mechanisms for osmoregulation, which causes death after a short period on freshwater. Teleost fish on the other hand, can adjust to reduced salinity for short periods of time since they have efficient osmoregulation mechanisms, allowing them to survive without damage. The hyposaline treatment was effective against Neobenedenia melleni in another grouper species (Epinephelus itajara) in Brazil, however, no previous studies were conducted on Epinephelus marginatus species. A dusky grouper (E.marginatus) was captured in Faial Island, Azores, to be sent to a public aquarium. The main goal of this study was the removal of the visible copepods found on the grouper, using the osmotic shock procedure, and a short characterization of those ectoparasites. The procedure was performed at Porto Pim Aquarium. The dusky grouper was put into a tank whereas the marine water was being slowly replaced with freshwater. As the salinity dropped, the visible ectoparasites fell from the fish, and were collected using nets on the tank and water outlets. Parasite samples were analysed through light microscopy, which resulted in the identification of Lepeophtheirus sp. specimens (Siphonostomatoida). A total of 540 parasites were collected and their sex ratio was estimated (15:10). Lepeophtheirus sp. individuals were measured both in width and length, measuring a total of 200 individuals (100 males and 100 females randomly collected). After the freshwater dip procedure, no more visible parasites were found on the grouper, which leads to the conclusion that this method was efficient for this species. Although some Caligidae species resist to salinity drops, becoming temporarily inactive in a numbness state until the salinity rises again, in the present study all the parasites were dead after the osmotic shock and the grouper appeared to be clear of ectoparasites. Keywords: copepod, Epinephelus marginatus, Lepeophtheirus sp, parasite, Grouper, Caligidae, Osmotic shock Conference: IMMR | International Meeting on Marine Research 2016, Peniche, Portugal, 14 Jul - 15 Jul, 2016. Presentation Type: Poster presentation Topic: Biodiversity, Conservation and Coastal Management Citation: Rodrigues AM, Silva LM, Gonçalves SC, Correia JP, Rosa RM and Vieira NS (2016). Short report on the ectoparasitic fauna from a wild Epinephelus marginatus and osmotic shock efficiency on their removal. Front. Mar. Sci. Conference Abstract: IMMR | International Meeting on Marine Research 2016. doi: 10.3389/conf.FMARS.2016.04.00068 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 12 Apr 2016; Published Online: 13 Jul 2016. * Correspondence: Prof. Sílvia C Gonçalves, MARE - Marine and Environmental Sciences Centre, School of Tourism and Maritime Technology, Polytechnic Institute of Leiria, Peniche, 2520-641, Portugal, scgoncalves@ipleiria.pt Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Alfredo M Rodrigues Luís M Silva Sílvia C Gonçalves João P Correia Rui M Rosa Nina S Vieira Google Alfredo M Rodrigues Luís M Silva Sílvia C Gonçalves João P Correia Rui M Rosa Nina S Vieira Google Scholar Alfredo M Rodrigues Luís M Silva Sílvia C Gonçalves João P Correia Rui M Rosa Nina S Vieira PubMed Alfredo M Rodrigues Luís M Silva Sílvia C Gonçalves João P Correia Rui M Rosa Nina S Vieira Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. 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