Haematological studies of Oreochromis niloticus exposed to diesel and drilling fluid in Lagos, Nigeria.

Abstract

Haematological changes in Oreochromis niloticus after exposure to diesel (23.4 mg/L) and drilling fluid (492 mg/L) for 28 days was investigated. The blood parameters of O. niloticusrevealed a significant decrease in haemoglobin only in fish exposed to drilling fluid and mean cellular volume (MCV), in both diesel and drilling fluid. Blood parameters of the fish such as mean cellular haemoglobin (MCH) and mean cellular haemoglobin concentration (MCHC) increased significantly in both treatments. Significant increase in thrombocytes was also observed although only in fishes exposed to diesel. Diesel and drilling fluid evoked significant changes in the haematological parameters of O. niloticus, a fish that has great potentials in the culture fishery of Nigeria.   Key words:  Haematology, Oreochromis niloticus, diesel, drilling fluid, Nigeria,