Toxicological effects of selenium on the haematological parameters of a freshwater catfish, Heteropneustes fossilis (Bloch)

Freshwater catfish, H. fossilis were exposed to selenium for acute (1.77 mg.L⁻¹) subacute (0.88 mg.L⁻¹) and sublethal (0.59mg.L⁻¹) concentrations at different time intervals. The LC₅₀ value of Selenium for 96h is 8.85 mg.L⁻¹. Significant alterations were observed in the haematological parameters. The RBC, Hb, PCV, values exhibit significant decrease, whereas increase in the values of WBC and clotting time at acute, subacute and sublethal concentrations for 96h and short (10–20 days) term but no other changes were found on long (30–60 days) terms exposure.