Investigation of Selected Heavy Metals, Histopathological and Oxidative Stress Responses of Nile Tilapia, Oreochromis niloticus in Water from the Hadejia-Nguru Wetlands Nigeria

Hadejia-Nguru wetland has been known to be a productive area of Agricultural engagements and fisheries activities allowing for intensive farming fishing activities, effluents from agricultural sewage, chemical seepages enter this water body. This study investigated the levels several heavy metals Mercury (Hg), Lead (Pb), Cadmium (Cd),Chromium (Cr), Aluminum (Al) in O. niloticus tissues (gills, liver, muscle) collected five sampling sites area. Tissue histology presence antioxidant enzymes revealed degree tissue damage stress fish. The results showed concentrations order Hg>Cr>Pb>Al>Cd, which are higher than maximum residue limits recommended by FAO WHO. Superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), reduced glutathione (GSH) were observed at high gills, muscle. Liver fish level SOD concentration 18.3μg/ml, followed 16.93 μg/ml CAT with 1.48 U/ml was MDA highest liver 1.08n/mol there no significant difference between other organs (P < 0.05). Reduced 18.36 seen Histopathology select i.e. muscle cells that affected toxicity environment. metal toxicity, enzymes, is an indication contamination serves as means monitoring safety freshwater organisms.