PRERELEASE DISEASE TREATMENT WITH POTASSIUM-PERMANGANATE FOR FALL CHINOOK SALMON SMOLTS

Standard potassium permanganate treatment (2 mg KMnO4/L freshwater for 1 h on three consecutive days) was applied to presmolts (parr) and sm olts of fall chinook salmon (Oncorhynchus tshawytscha). Smoltification was determined by gill Na+, K+-ATPase activity. Treatments were condu cted 73, 59, 45, 31, 16, and 2 d prior to full-strength seawater entry in aquaria. Potassium permanganate did not affect either growth or su rvival in seawater over 25 d. We observed a delayed rise in gill Na+,K +-ATPase activity in fish treated 16 d prior to seawater entry.