Vet World   Vol.10   August-2017  Article-21

Subchronic toxicity of Nile tilapia with different exposure routes to Microcystis aeruginosa: Histopathology, liver functions, and oxidative stress biomarkers

Background and Aim: Three-week subchronic exposure experiment was carried out on Nile tilapia, to determine their effects on fish behavior, tissues, liver functions, antioxidant enzymes, and lipid peroxidation.

Materials and Methods: Fish were exposed to four main treatments; orally fed diet plus toxic cells of M. aeruginosa (containing 3500 μg/g MC-LR), immersion in 500 μg MC-LR/L, intraperitoneal injection of M. aeruginosa MC-LR with a dose of 0.1 ml of extracted toxin at a dose of 200 μg/kg bwt, and the fourth one served as a control group, then the fish were sacrificed at the end of 3rd week of exposure.

Results: The results revealed no recorded mortality with obvious behavioral changes and an enlarged liver with the congested gall bladder. Histopathology demonstrated fragmentation, hyalinization, and necrosis of the subcutaneous musculature marked fatty degeneration, and vacuolation of hepatopancreatic cells with adhesion of the secondary gill lamellae associated with severe leukocytic infiltration. Furthermore, liver functions enzymes (aspartate aminotransferase and alanine aminotransferase, and the activities of glutathione peroxidase, glutathione reductase, lipid peroxidase, and catalase enzymes) were significantly increased in all treatments starting from the 2nd week as compared to the control levels.

Conclusion: In this context, the study addresses the possible toxicological impacts of toxic M. aeruginosa contain MC-LR to Nile tilapia, and the results investigated that MC-LR is toxic to Nile tilapia in different routes of exposure as well as different doses. Keywords: catalase, lipid peroxidation, Microcystis aeruginosa, microcystins, Nile tilapia.

Keywords: catalase, lipid peroxidation, Microcystis aeruginosa, microcystins, Nile tilapia.

How to cite this article: Abdel-Latif HMR, Khashaba AMA (2017) Subchronic toxicity of Nile tilapia with different exposure routes to Microcystis aeruginosa: Histopathology, liver functions, and oxidative stress biomarkers, Veterinary World, 10(8): 955-963.

Received: 21-05-2017  Accepted: 28-07-2017     Published online: 21-08-2017

Corresponding author: H. M. R. Abdel-Latif   E-mail: hmhany@alexu.edu.eg

DOI: 10.14202/vetworld.2017.955-963

Copyright: Abdel-Latif HMR and Khashaba AMA, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.