Is Radix peregra a new intermediate host of Fascioloides magna [Trematoda] in Europe? Field and experimental evidence

Rediae and immature cercariae of the giant liver fluke, Fascioloides magna, a pathogenic and important parasite of game animals, were found in 6 out of 7,277 Radix peregra (Gastropoda, Lymnaeidae) from two localities in Western and Central Bohemia, Czech Republic. In one of these localities a relatively high infection of Galba truncatula (26 out of 76) with mature cercariae of F. magna was detected. R. peregra, which is dominant over Galba truncatula, has never been reported as the natural intermediate host of F. magna. Its potential susceptibility to F. magna infection was confirmed experimentally with 67 snails of R. peregra (out of 371) infected. The present data indicate the capability of F. magna to expand the spectrum of its intermediate hosts and demonstrate the potential epizootiological importance of lymnaeid snails, other than G. truncatula, for transmission of the parasite in Europe.