Submitted to: Proceeding of World Aquaculture Society
Publication Type: Abstract Only
Publication Acceptance Date: 4/26/1999
Publication Date: N/A
Technical Abstract: Ich is a common ectoparasite that invades the skin and gills of many species of freshwater fish. Potassium permanganate has been used in the past to control infestations of Ich, but its toxicity to the free-swimming theront is not known. The toxicity of this compound is reduced as the organic content of the water increases; this can be attributed to rapid chemical reduction of the permanganate anion to less toxic manganese compounds in the presence of oxidizable organic matter. In the present study, reconstituted hard water was used to eliminate the effects of organic matter, and the acute toxicity of potassium permanganate was observed. Ich was maintained by serial infestation using channel catfish as the host. Mature trophonts were gently scraped from the fish and placed into a small beaker containing tank water. The trophonts were allowed to adhere to the beaker for 1 hr and were then rinsed with reconstituted hard water to remove organic matter, and incubated for 24 hrs to allow for mitotic division. The theronts were exposed to concentrations of potassium permanganate ranging from 0.05 to 2 mg/l in 96 well microtiter plates and the toxicity was observed over a period of several hours. Results indicated that relatively low concentrations of potassium permanganate are toxic to Ich theronts. Ongoing research will focus on the effect of organic matter and water chemistry on toxicity and efficacy of potassium permanganate in the treatment of Ich in catfish.