Oral pharmacological treatments for parasitic diseases of rainbow trout oncorhynchus mykiss. III. Ichthyobodo necator.

A total of 32 drugs were evaluated as regards their efficacy for oral treatment of Ichthyobodo necator infestation of rainbow trout. In preliminary trials, all drugs were supplied to infected fish at 40 g per kg of feed for 10 d. The majority of the drugs tested (1,3-di-6-quinolylurea, aminosidine, amprolium, benznidazole, bithionol, chloroquine, diethylcarbamazine, dimetridazole, diminazene aceturate, febantel, flubendazole, ketoconazole, levamisole, mebendazole, netobimin, niclosamide, niridazole, nitroscanate, nitroxynil, oxibendazole, parbendazole, piperazine, praziquantel, ronidazole, sulphaquinoxaline, tetramisole, thiophanate, toltrazuril and trichlorfon) were ineffectdive. Metronidazole and secnidazole were 100% effective (unlike the other nitroimidazoles tested, namely dimetridazole, benznidazole and ronidazole). The non-carbamate benzimidazole triclabendazole was likewise 100% effective.