Assessment of the sub-lethal effects of Sarosate ® on the liver and gills of Clarias gariepinus juveniles (Burchell, 1822)

Abstract

One hundred and twenty (120) Clarias gariepinus juveniles of average weight 24.8 ± 15.6 g were exposed to sub-lethal doses of Sarosate ® (0 mg, 0.10 mg, 0.15 mg and 0.20 mg) per liter of clean borehole water for 14 days after acclimatization to assess the toxicity on some internal organs. Exposed fishes were selected at day 1, 7 and 14, sacrificed and the liver and gills removed, fixed immediately in Bouin’s fixative and thereafter processed for photomicrograph. Normal liver and gill architecture were observed in the control. However, effects ranging from mild infiltration of inflammatory cells to portal aggregate of inflammatory cells were observed in exposed fish liver samples. Also, mild detachment of gills from the epithelium, distortion of gill filament and some ghost like appearance of the gill (necrosis) were observed. The observed features indicated toxicity effects of the herbicide on Clarias gariepinus hence could be useful biomarkers of toxicant exposure.