International Journal of Histology and Cytology

International Journal of Histology and Cytology Vol. 1 (4), pp. 031-036, April, 2014. © International Scholars Journals

Full Length Research Paper

Histological changes in liver, gills and kidney of catfish (Heterobranchus bidorsalis) exposed to cypermethrin concentration

Adebola K.* and Folorunsho Ayo

Department of Fisheries and Aquaculture Technology, Faculty of Agricultural Sciences, University of Ibadan, Nigeria.

E-mail: [email protected]

Accepted 12 March, 2014

Abstract 

Fingerlings of Heterobranchus bidorsalis (mean weight 11.88 g) were exposed to various sub-lethal concentrations of cypermethrin (0.032, 0.034, 0.036, 0.038 and 0.040 ml/L), a toxicant, and the histological effects were recorded. The 96 h bioassays were also conducted to determine the lethal concentration (LC₅₀) of cypermethrin on the test fish. The 96 h LC₅₀ of H. bidorsalis exposed to Cypermethrin was 0.036 ml/L. The physical reactions observed in the fish were: discolorations of the skin, erratic swimming, loss of reflex, hyperactivities, surfacing, and these effects increased with increasing concentration of the toxicants and duration of exposure. The pH and dissolved oxygen of the test media showed slight decrease from lowest concentration (0.032 ml/L) to the highest concentration (0.040 ml/L) while the temperature increased slightly with increasing concentration (0.032, 0.034, 0.036, 0.038 and 0.040 ml/L). The histological examination of the gills, kidney, livers of the fish after 96 h showed pathological changes and alterations such as gills infiltration, inflammation of the livers, vacuolation and necrosis. There was excessive necrosis degeneration in higher concentrations (0.038 and 0.040 ml/L) and there was increase in mortality as the concentrations increased.

Key words: Histology, cypermethrin, xenobiotic, Heterobranchus bidorsalis, acute toxicity, LC₅₀.