Toxicological evaluation of methanol extract of Khaya senegalensis leaves in African catfish Clarias gariepinus

Abstract

The toxicity of methanol extract of Khaya senegalensis leaves was evaluated in Clarias gariepinus over 96 h exposure. The fish were exposed to 150 mg/L. 170 mg/L. 190mg/L, 210 mg/L and 230 mg/L of the extract and a control in acute static bioassay after a trial finding to determine the median lethal concentration (LC₅₀) of the extract. Exposed fish showed clinical signs, such a distress opercula ventilation, tail fin beats and  respiratory alteration. The frequency of opercula ventilation and tail fin beats were concentration dependent and showed significant association (P<0.05). The LC₅₀ value of 199,69mg/L was established for the extract in the exposed fish where mean mortally was significantly (P<0.05) concentration and exposure dependent. This plant is to be regarded as a piscine toxicant and should be discarded from the bank of rivers and dams.

Keywords: Acute effect, Histopathology, Khaya senegalensis, Clarias gariepinus