Acute toxicity of liquid organic fertilizer to juveniles of <i>Clarias gariepinus</i>

Abstract

The study was carried out to determine the acute toxicity of liquid organic fertilizer to juveniles of Clarias gariepinus. Clarias gariepinus juveniles were exposed to different concentrations of liquid organic fertilizer for 96 hours under static conditions. The LC50 was calculated to be 328.10ml/L with Lower and upper confident limits of 275.02 ml/L and 391.42 ml/L respectively. At the contact phase there was a brief period of high excitability, visible avoidance characterized by fast swimming, leaping and attempts to jump out of the test medium, loss of equilibrium, followed by lethal (death) phase. There was no significant difference between the various mean values of temperature and pH (P > 0.05). The study revealed that acute concentrations of the liquid organic fertilizer were harmful to Clarias gariepinus juveniles. Liquid organic fertilizers could be applied in fresh water fish ponds and allowed for a period of time to break down through natural processes before stocking. Indiscriminate use of liquid organic fertilizer could also be avoided.