Global Journal of Fisheries Science

In this study, the tolerance of Clarias gariepinus finger-lings (15.5 g) to chemotherapeutic doses of potassium permanganate was investigated. The experiment was done in 15 plastic tanks (106 each) in hatchery facilities by testing ten doses of potassium permanganate in two experimental batches; 1.0, 3.0, 5.0, 7.0, and 0.0 mg/L in batch one and 0.5, 2.0, 4.0, 6.0, and 0.0 mg/L in batch two, for three duration periods (0, 3 and 6 days) in three replicates. Blood samples were obtained and parameters such haematocrit, haemoglobin concentration, red blood cells (RBCs), and white blood cells (WBCs) were measured. The internal parasites in organ tissue and blood were investigated and the mortality and survival rate were evaluated. Empirical data of the results obtained were subjected to statistical analysis using two-way ANOVA. The results of analysis data showed high variation (p<0.05) in the hematological profiles of treated fish under varying levels of potassium permanganate and exposure duration periods (15.24 to 9.74, 32.04 to 18.74, 8582.0 to 13140.0 and 9.11 to 3.71 for Hb, PCV, WBCs and RBCs respectively), which resulted in varying levels of stresses and some biological, biochemical and physiological changes in the fish. The investigation of blood and internal tissues parasites revealed no infectious cases (p<0.05). These results show that potassium permanganate can negatively affect the hematology of Clarias gariepinus, leading to various stress levels with serious deterioration of fish health and a dramatic increase in mortality rate. It is recommended that 2 to 3 mg/L concentrations of potassium permanganate are suitable for treatment without causing tolerance and at the same time can be used in controlling external infection.