Bioindication potential of Nile Tilapia (<i>Oreochromis niloticus</i>) from Otto River in Unale, Ibaji Local Government Area, Kogi State

Abstract

The aim of the study was to assess the bio-monitoring potential of Nile Tilapia (Oreochromis niloticus) from Otto River in Unale, Ibaji L.G.A, Kogi State, Nigeria.Fifteen samples of Nile Tilapia together with water samples were collected from Otto River in Unale. Oreochromis niloticus and water samples were also collected from unpolluted river of Ebocho in Odeke in the same LGA to serve as control for the study. Heavy metals (i.e., Pb, Cd, Cu and Zn) concentrations, length-weight relationship and condition factor were determined on the fish samples. Nitrate, nitrite, Dissolved Oxygen (DO) and salinity were determined for the water samples.The concentration of lead and cadmium was above the WHO permissible limits while copper and zinc were below WHO permissible limits. Decreasing order of heavy metals concentration was Pb>Cd>Cu>Zn. The water quality parameters were within the permissible limits. The isometric growth pattern observed in this study is an indication that the fishes are in good health conditions. The condition factor values (>1) of the studied fish samples suggests that the physico-chemical quality of river Otto favours the well-being of fish samples studied. The high accumulation of lead and cadmium in the fish samples suggests that anthropogenic activities are going on around the river.

Keywords: Bio-monitoring, Heavy Metal, Condition Factor, Anthropogenic