Histological assessment of gills and liver of Oncorhynchus mykiss exposed to sublethal concentrations of the antibiotic erythromycin

Abstract

Event Abstract Back to Event Histological assessment of gills and liver of Oncorhynchus mykiss exposed to sublethal concentrations of the antibiotic erythromycin Sara Rodrigues1*, Sara C. Antunes1, Bruno S. Nunes2 and Alberto T. Correia3 1 FCUP and CIIMAR, Portugal 2 CESAM and DBio, Portugal 3 UFP and CIIMAR, Portugal The ever-increasing presence of therapeutic drugs in the aquatic environment has been systematically reported during the past years. Among these substances, antibiotics are particularly important because they are widely used in medical and veterinary practice, livestock production and aquaculture. Erythromycin (ERY) is a macrolide antibiotic, which is widely used in human therapeutics, but also in aquaculture practices. ERY was already detected in surface waters, in levels between several 19.2 ng/L to 1 μg/L. Therefore, it is necessary to characterize its potential ecotoxicological effects, including tissue modifications in target and non-target species. Histological assessment of different tissues of exposed fish are useful tools for ecotoxicological studies, helping to establish causal relationships between contaminant exposure and several biological responses. This study assessed the acute and chronic histopathological effects of erythromycin in Oncorhynchus mykiss. Gills and liver of rainbow trout were examined histologically after acute (0.001, 0.010, 0.100, 1.000 and 10.00 mg/L) and chronic (0.05, 0.10, 0.20, 0.40 and 0.80 µg/L) exposures. A qualitative and semi-qualitative evaluation of both tissues was performed, and also a quantitative evaluation of various lamellar structures (morphometric measurements) and PAGE index (proportion of the secondary lamellae available for gas exchange). In both exposures, proliferative and degenerative alterations were the most predominant changes in gills. Organisms exposed to the highest concentrations of erythromycin had significant higher gill pathological indices in both acute and chronic experiments. Significant alterations in morphometric measurements and a decrease in the PAGE index were also observed. O. mykiss exposed to ERY had slightly higher levels of degenerative and circulatory alterations in liver. The liver pathological index increased significantly with higher concentrations for both exposures. The hereby results suggest a cause-effect relationship at environmentally relevant concentrations between the exposure to ERY and the histological damage. Keywords: Erythromycin, rainbow trout, Gills, Liver, histopathology Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Poster Presentation Topic: Physiology, Behavior and Toxicology Citation: Rodrigues S, Antunes SC, Nunes BS and Correia AT (2015). Histological assessment of gills and liver of Oncorhynchus mykiss exposed to sublethal concentrations of the antibiotic erythromycin. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.FMARS.2015.03.00203 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: 07 Dec 2015; Published Online: 07 Dec 2015. * Correspondence: Dr. Sara Rodrigues, FCUP and CIIMAR, Porto, Portugal, up201208875@fc.up.pt Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Sara Rodrigues Sara C Antunes Bruno S Nunes Alberto T Correia Google Sara Rodrigues Sara C Antunes Bruno S Nunes Alberto T Correia Google Scholar Sara Rodrigues Sara C Antunes Bruno S Nunes Alberto T Correia PubMed Sara Rodrigues Sara C Antunes Bruno S Nunes Alberto T Correia Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.