Acute Toxicity of Mercury Chloride on Fingerlings of Clarias gariepinus
Nwakanma, C., & Ochukor, C.M
Department of Environmental Management and Toxicology
College of Natural Resources and Environmental Management
Michael Okpara University of Agriculture, Umudike, Abia State, Nigeria
Email:dr.nwakanmac@gmail.com
ABSTRACT
In this study, 90 fingerlings of Clarias gariepinus were divided into six treatments of five fish each. The different groups were exposed to the different concentrations of 0mg/L, 2mg/L, 4mg/L, 6mg/L, 8mg/L and 10mg/L for a period of 96 hours. The experiment was triplicated. The results revealed that all the fish of treatments exposed to 0mg/L of Hgcl2 (control) survived whereas all the fish of treatments exposed to 8mg/L and 10mg/L died. The determination of 96 hours LC50 was carried out by computing the mortality result in probit program of SPSS. The median lethal concentration was 0.55mg/L with lower and upper confidence limits of 3.188mg/L and 6.96mg/L respectively. Also in this study, the histopathological alteration in the muscle tissue of Clarias gariepinus caused by the mercury chloride were observed. After 96 hours of introducing different concentration of mercury chloride of the determination of 96 hours LC50. The control (0mg/L) shows the fish skeletal muscle tissue with evenly sized muscle bundles displaying typical but less obvious cross striation as well as thick intermuscular connective tissue while the highest concentration (10mg/L) compared to 0mg (control) shows there is severe variability in muscle bundle size, accentuation of cross striations and severe reduction of muscle density with prominent myonecrosis as well as moderate thinning of intermuscular connective tissue.
Keywords: Toxicity, Clarias gariepinus, Mercury Chloride, Histopathology
