Toxicity effect of African mesquite (Prosopis africana) seed on African catfish (Clarias gariepinus) juveniles

Toxicity test of African Mesquite (Prosopis Africana) seed on African Catfish (Clarias gariepinus) was carried out to determine the acute lethal concentration (LC50) in 24 – 48 hours. Two hundred and fifty (250) juveniles were acclimatized in the laboratory for 14days. Ten (10) fishes were placed in each of the experimental plastic containers, containing test concentrations of 0 ml, 10 ml, 20 ml, 40 ml, 80 ml, 160 ml, 320 ml and 640 ml/liter of water. The 24 and 48 hours LC50 of Prosopis africana applied to Clarias gariepinus juvenile were 118.25ml/l and 53.70ml/l respectively. Toxic reactions exhibited by the fish include erratic movement, air gulping, and loss of reflex. Mortality increased with increase in concentration of Prosopis africana and time of exposure in Clarias gariepinus juveniles. The acute toxicity that killed all the fish within 24 hours was discovered to be the highest concentration (640ml/l) of the extract. It is then recommended that Prosopis africana plant should be used as organic piscicide and further study on the toxicity of Prosopis africana plant on other commercially viable fish be studied.Keywords: Bioassay, Extract, Toxicity, Concentration, Mortalit