Acute toxicity of <i>Jatropha curcas</i> (barbados nut) latex extracts to <i>Oreochromis niloticus</i> juveniles

Abstract

The effects of the latex extract of Jatropha curcas on mortality rate, opercular ventilation rate and some behavioural responses of Oreochromis niloticus juveniles were investigated under laboratory conditions over a 96 hours exposure period. Juveniles of Oreochromis niloticus (Trewavas) were exposed in plastic aquaria to 0.00mg.l-1 (control), 10mg.l-1, 15mg.l-1, 20mg.l-1, 25mg.l-1 and 30mg.l-1. Their opercular beats per minute, tail fin beats per minute, mortality and probit kill were determined. Symptoms of toxicosis observed include agitated swimming, loss of equilibrium, air gulping, periods of quiescence and death. Within 24 hours the opercular ventilation beats and tail fin beats of the exposed fish were significantly higher than in control fish (p<0.05). At 72 hours and 96 hours the opercular and tailfin beats in the control fish were significantly higher (P<0.05) than the exposed fish. The 96 hours LC50 was determined as 5.23 ml/l. Include significance of this study to conclude abstract.

Key words: acute toxicity, Jatropha curcas latex extract, Oreochromis niloticus, haematological parameters.