©Association for Aquatic Sciences of Nigeria (ISSN: 0189-8779)
Journal of Aquatic Sciences 28 (1): 105- 112 (2013)
ACUTE TOXICITY OF CRUDE Euphorbia tirucalli LATEX EXTRACTS TO Oreochromis niloticus JUVENILES
M. USMAN1, A.M. ABARI1 AND S.A. OKUNSOBOR2
1 Department of Fisheries, College of Agriculture, P.M.B 33, Lafia. Nasarawa State.
2 Department of Wildlife, Forestry and Fisheries, Faculty of Agriculture, Nasarawa State University,
P.M.B 135. Lafia. Nasarawa State.
Acute toxicity of crude Euphorbia tirucalli latex extracts to Oreochromis niloticus juveniles was investigated in the College of Agriculture, Lafia.A four day static acute toxicity test was performed to determine the LC50 value of crude Euphorbia tirucalli latex extract for the fresh water fish, Oreochromis niloticus. Various concentrations of the toxicant were prepared as 0.00 ml/L (control), 10 ml/L, 15 ml/L1, 20 ml/L, 25 ml/L and 30 ml/L respectively. The LC50 values, their upper and lower confidence limits and slope were calculated. The acute toxicity of crude Euphorbia tirucalli latex extract exhibited a positive correlation between fish mortality and exposure periods. It was found that latex of Euphorbia tirucalli had higher piscicidal activity as compared with other synthetic pesticides, organophosphates and pyrethriod for Oreochromis niloticus. Hence, adequate precautions must be exercised when Euphorbia tirucalli latex is being used near fish-inhabiting water reservoirs and/or as ornamental plant.
Key Words: Toxicant, Euphorbia tirucalli, Oreochromis niloticus, haematological parameters, fish death