Occurrence of acanthocephalans in the Eurasian otter Lutra lutra (L.) (Carnivora, Mustelidae) in Bulgaria, with a survey of acanthocephalans recorded from this host species

Three Eurasian otters (Lutra lutra) originating from Pazardzhik Region (South Bulgaria) were examined for helminth parasites. Three species of acanthocephalans were recorded: Pomphorhynchus laevis, Acanthocephalus anguillae and A. ranae. These species are not specific parasites of otters, the former two occurring in various freshwater fishes and the latter being a parasite of anurans. A review of acanthocephalan species recorded from L. lutra is presented. The possible transmission routes by which otters become infested with acanthocephalans are considered to be either paratenic transfer of encysted extra-intestinal juveniles in paratenic hosts or postcyclic transmission of mature intestinal worms in definitive hosts.