Changes in haematological parameters of Tilapia guineensis exposed to different concentrations of detergent under laboratory conditions
The haematological changes in Tilapia guineensis exposed to sub-lethal concentrations of detergent were investigated. One hundred and eighty adult T. guineensis (mean length 17cm+2.61 SD and mean weight 145.22g+3.14 SD), were exposed using static renewal assay to different concentrations (0.00, 0.50, 1.00, 1.50, 2.00 and 2.50 mg/L) of detergent for 15 days. The experiment evaluated sub-lethal effect of the exposure on some haematological parameters including haemoglobin (Hb), red blood cell (RBC), packed cell volume (PCV), white blood cell (WBC), leucocrit, thrombocytes, neutrophils, lymphocytes, monocytes, mean corpuscular haemoglobin concentration (MCHC), mean corpuscular volume (MCV) and oxygen carrying capacity (OCC). The results showed a significant (P<0.05) reduction in the values of Hb, RBC, PCV, leucocrit, thrombocytes, lymphocytes, MCHC, and OCC, with increasing concentrations of the toxicant. However, exposure of T. guineenisis to detergents caused significant elevation in the values of WBC, neutrophils, monocytes, MCV and MCH when compared to the control values. Exposure of this species to sub lethal levels of detergents altered some components of its haematological variables, which may lead to abnormal metabolism of the fish. Therefore, there is need for proper disposal of domestic wastes containing detergent into the aquatic environment.
Keywords: Detergent, toxicity, aquatic environment, haematology, tilapia