Studies on the invasion of Notocotylus attenuates (Notocotylidae: Digenea) into its snail host, Lymnaea peregra. In vitro observations on the hatching mechanism of the egg

Abstract

SUMMARYMedia are described which stimulate the eggs of Notocotylus attenuatus to hatch in vitro. Hatching involves opening of the operculum and emergence of the opercular cord to form a tube measuring approximately 75 μm in length along which the sporocyst passes. The sporocyst is then released from the end of the tube. It is suggested that in vivo the opercular cord serves to inject the sporocyst through the snail host's gut wall into the haemocoel.