title: Apparent drug resistance to the organophosphate dimethyl (2,2,2-trichloro-1-hydroxyethyl) phosphonate by monogenetic trematodes.
abstract: Gyrodactylus elegans on goldfish, (Carassius auratus) from a commercial farm were resistant to recommended dosages of dimethyl (2,2,2-trichloro-1-hydroxyethyl) phosphonate. Controlled experiments suggest that a dosage 100 times the commonly recommended minimal dosage (.25 mg/l) was required to remove trematodes. A hypothesis is proposed to account for the development of drug resistant trematodes based on the life cycle of the parasites and continual drug exposure.
mesh_terms: D000818:Animals; D004351:Drug Resistance; D004625:Embryo, Nonmammalian / Q000187:drug effects; D005399:Fishes / Q000469:parasitology*; D009943:Organophosphorus Compounds / Q000008:administration & dosage*; D014200:Trematoda / Q000187:drug effects*
chemical_list: D009943:Organophosphorus Compounds