Acute Toxicity of Glyphosate on Clarias Gariepinus Fingerlings

The effects of glyphosate on mortality rate and behavioural responses of Clarias gariepinus fingerlings were investigated under laboratory conditions for 96 hours exposure period. The lethal concentration (LC50) value of glyphosate on fingerlings of Clarias gariepinus was 0.0018 ml/l for 96 hours of exposure. The regression equation was found to be Y= 9.132 + 1.365 * Log conc; R2 = 0.9277 (Y= probit kill). Fingerlings also exhibited several abnormal behaviours, including restlessness, uncoordinated movement, loss of equilibrium, air gulping and staying motionless at tank bottom. Oxygen consumption by fingerlings decreased with increased concentration of glyphosate.