White spot disease, also known as Ich, is a parasite disease caused by ciliated protozoan, Ichthyophthirius multifiliis. There are several chemicals can be used for treatment of disease such as formalin, sodium chloride, hydrogen peroxide (1). This study was performed in order to evaluate the effect of Furazolidone on Ichthyophtirius multifiliis, Furazolidone is a nitrofuran derivatives that interferes with parasitic enzyme. Although its exact mechanism of action is unknown. It is effective against Giardi sp. Coccidia, Trichomonas and some entric bacteria.(2) 120 Gold fish were divided in four groups with duplicated. Groups 1 to 3 experimentally infected with Ichthyophthirius multifillis in water temperature18C◦. Group 4 was not affected considered as control. 72 hours post - infection mortality was started in challenged groups. Presence of parasite was detected on the skin and fins of dead fish under microscopic examinations. Three days after mortality initiation, group 1 were treated by bath with 50 mg/L Furazolidone for one hour and group 2 were treated with formalin at concentration of 250 ppm for one hour. Fish in group 3 were not treated. Treatments were repeated after three days. The fish were monitored for 2 weeks. Dead fish were collected every day and monitored for Ich disease. After 2 weeks mortality in experiment groups were compared statistically. In this study the data were analyzed using t-student test and LSD test at level significance (p≤0.05. The result of this study shows the difference between mortality in groups were significant (p≤0.05). Mortality in Furazolidone exposed group was lower than other groups while higher death rate was in non-treated group and formalin group was in between. Mortality rate in Furazolidon group (1) ,formalin group(2), non-treated group (3)and control were 17%, 40%, 67%, 0 % respectively. However the results showed that Furazolidone is more effective than formalin againstIch disease but excess studies are necessary to
