Ultrastructural studies on the tegument of dicrocoelium dendriticum [Rudolphi, 1819] loss 1899

The tegument of Dicrocoelium dendriticum was studied by scanning and transmission electron microcopy. It consists of an anucleate surface syncytium and a deeper nucleated zone. The syncytial layer covers the entire surface of the fluke. It is connected to the nucleated zone through thin cytoplasmic strands. The syncytium is bounded by an apical plasma membrane, which is highly folded. This layer mainly contains abundant mitochondria of varying size and shape as well as two types of granules, dumbbell shaped and spherical. Although the apical surface shows active exocytosis, no evidence for endocytosis was observed. This study revealed the presence of this liver fluke in sheep imported from other counties