Recent achievements in the chemotherapy of myxosporean infections of fish.

Until quite recently, the therapy of fish diseases caused by myxosporeans has been an unsolved problem. Fumagillin is the only effective drug which can be successfully applied against several myxosporeoses in the form of prolonged feeding. It has been used with good results against sphaerosporosis of common carp, hoferellosis of goldfish, myxidiosis of eel, and proliferative kidney disease, whirling disease and ceratomyxosis of salmonids. Already a 4- to 6-day feeding of medicated diets containing 0.05-0.1% fumagillin was effective against the early blood stages of Sphaerospora, while toltrazuril failed to kill these parasites.