Biomarkers of toxicity inClarias gariepinusexposed to sublethal concentrations of polycyclic aromatic hydrocarbons

Sublethal concentrations of dichlorvos and paraquat induce genotoxic and histological effects in the Clarias gariepinus

“…The fish were fed twice daily with commercial Coppens fish feed (size: 1–3 mm) and water was changed daily in the holding tanks to prevent accumulation of toxic waste substances. Feeding was stopped 24 h prior to exposure of fish to test chemicals [ 31 ].…”

“…Fish were considered dead when there was no movement and the body was floating horizontally at the top or sinking at the bottom of the test media. Dead fish were removed and disposed immediately to prevent contamination of the test media [ 31 ].…”

“…The juveniles were exposed to 73 μg/L (10% 96-h LC 50 ), 7.3 μg/L (1% 96-h LC 50 ) for dichlorvos and 5 μg/L (10% 96-h LC 50 ), 0.5 μg/L (1% 96-h LC 50 ) for paraquat and control (water alone). A semi-static bioassay protocol was followed in which the test media was changed every 48 hours to prevent contamination of the test media with waste metabolites [ 31 , 32 ].…”

“…Following this, they were embedded in paraffin and then manually sectioned with a microtome at 4–5 μm. The sections were dewaxed and stained with hematoxylin and eosin (H&E) and examined using a digital light microscope (Leica® DM500) [ 31 ].…”

Haematology, Oxidative Stress and Micronuclei Frequency of Clarias Gariepinus Exposed to Glyphosate based Herbicide Glycot® GBHG

“…Sancho et al (2000) noted that teleost fish have proved to be good models to evaluate the toxicity and effects of contaminants on animals since their biochemical responses are similar to those of mammals. The African catfish C. gariepinus is an important economic fish found in most African rivers and is considered as a potential bioindicator species (Shagbanmu et al, 2018).…”