The development of Echinostoma hortense in several fresh water fishes fixation in 70 % ethyl alcohol and Hematoxylin-eosin stained was microscopic observed. The eggs from adult flukes collected from the intestine of rats were cultivated to miracidia, and exposed to Radix auricularia snails. The cercariae shed from the snails (Radix auricularis) were again exposed to several species of fresh water fishes in order to observe metacercaial formation in the fishes.
The results obtained in this study were as follows:
Cercaria were experimentally placed together with the fishes in a beaker containing tapwater. Three hundred cercaria were exposed to each fresh water fishes (Misgrunus anguillicaudatus, Moroco oxycephalus, Pseudogobio esocinus, Zaco platypus). Infectivity to each fresh water fishes was 33.3 % in Misgrunus anguillicaudatus and 30.6 % in Moroco oxycephalus and Pseudogobio esocinus, and 22.6% in Zacco platypus, respectively.
Cercaria wandering around the fresh water fishes attacked at the head part, fins area, scale or body surface within 30 min to two hours. It took approximately more then two hours until the metacercaria have completed invading the fishes. The metacercariae revealed peculiar distribution in body of the fresh water fishes. They were most frequently found from the head part including gill (M. auguillicaudatus 40%, M. oxycephalus 66.3%, P. esocinus 27.2% and Z. platypus 22.6%) and fins area.
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