Potassium permanganate as therapeutic agent in control of Epistylis sp. in cachara Pseudoplatystoma reticulatum and its effects an hematology

Abstract

The early phase of South American carnivorous catfish is commonly affected by ectoparasites. The use of the potassium permanganate (KMnO₄) as therapeutic agent for control of the natural infestation by ciliate protozoan Epistylis sp. in cachara juveniles, Pseudoplatystoma reticulatum, and its effects on hematology was evaluated in this study. The fish were submitted to three therapeutic baths, lasting 20 min in intervals of 48 h, with potassium permanganate in the concentrations of 0.0 mg L^-1 (control); 1.0 mg L^-1; 2.5 mg L^-1 and 4.0 mg L^-1. The different levels of the potassium permanganate tested did not interfere (P>0.05) in survival. The smaller (P<0.05) prevalence was observed in the concentration of 2.5 mg L^-1 (6.67 ± 6.70%). Effect on the erythrogram was not observed (P>0.05). The fish treated with the potassium permanganate in the concentration of 1.0 mg L^-1 showed higher percentage (P<0.01) of special granulocytic cells (SGC) in relation to that treated with the concentration of 2.5 mg L^-1; 4.0 mg L^-1 and control group. Independent of the concentration, the treated fish showed smaller absolute value of eosinophils (P<0.01) in relation to fish of control group. Potassium permanganate in the concentration of 2.5 mg L^-1 was effective in the control of the ciliate protozoan Epistylis sp. in cachara juveniles naturally infected.