Nitrofurazone for Control of the Microsporidan Parasite Pleistophora Ovariae in Golden Shiners

Abstract

Abstract In a test of the efficacy of nitrofurazone to control infection of the Microsporidan parasite Pleistophora ovariae in ovaries of golden shiners (Notemigonus crysoleucas), the chemical was fed at levels of 1.10, 1.65, 2.20, 3.30, 5.51, and 7.71 g active ingredient per kilogram of feed (50-350 g/100 lb). The dosage response was nonlinear; maximal drug effect on incidence of infection was at a dose of 2.20 g and maximal effect on intensity of infection was at 3.30 g. The net production of shiners (not evaluated at the three highest treatment levels) was reduced in a pond in which the fish were given the 2.20-g treatment, suggesting that high levels of this drug may inhibit gonad development. None of the dosages tested yielded a complete cure.