Abstract
The prophylactic effects of chemicals and immunostimulants on theTetrahymena infection of guppies (Poecilia reticulata) were studied through experimental infections.Tetrahymena pyriformiswas used in an experimental infection on a guppy population pre-treated by the following method; the base of the caudal fin was covered with a 10% acetic acid-soaked cotton strip for 3 min. The study consisted of screening anti-Tetrahymenachemicals, testing prophylactic effects of selected chemicals or immunostimulants, and finally evaluating the combination effects of the chemicals and immunostimulants. The single uses of chemicals or immunostimulants did not completely prevent theTetrahymenainfection. Prevention was attained by the combination of a 0.5% sodium chloride bath and a feeding of C-UPIII (a Chinese herb mix) diet.