Parasites of Myocastor coypus – a Comparison in Farm Animals and Their Feral Counterparts

Abstract The parasitic status in the coypus (nutrias) Myocastor coypus, both farm-bred or free-living on river banks in the Czech Republic, was determined. Faecal samples were collected from 200 coypus originating from 11 farms (farm-bred animals) and from 20 individuals living at 14 natural localities (feral animals). Faeces were examined for nematode eggs and coccidian oocysts using the McMaster method. The evaluation of faeces from farm-bred coypus indicated infection with the following parasites: Trichuris sp., Strongyloides sp., Trichostrongylus sp., Eimeria seidelli, Eimeria nutriae, Eimeria coypi, and Eimeria myopotami. Free-living feral rodents harboured Eimeria nutriae, E. coypi, Strongyloides sp. and in one case also Trichuris sp. An additional visceral examination of 20 coypus originating from five farms revealed two nematode species in the gastrointestinal tracts, namely Trichuris myocastoris and Strongyloides myopotami. The study indicated that feral coypus are far less parasitized than their captive counterparts.