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Life Cycle of F. buski. (1)Immature eggs are discharged into the intestine and
stool. (2)Eggs
become embryonated in water, (3)eggs release miracidia , (4)which invade a
suitable snail
intermediate host . In the snail the parasites undergo several developmental stages
(sporocysts, rediae, and cercariae). (5)The cercariae are released from the snail
and (6)encyst
as metacercariae on aquatic plants. The mammalian hosts become infected by ingesting
metacercariae on the aquatic plants. (7)After ingestion, the metacercariae excyst in
the duodenum and (8)attach to the intestinal wall. There they develop into adult flukes
(20 to 75 mm by 8 to 20 mm) in approximately 3 months, attached to the intestinal wall of the mammalian
hosts (humans and pigs). The adults have a life span of about one year.
Image and text
taken from The
Centers for Disease Control |
Common species of intermediate host snail:
Planorbid snails of the genera Segmentia, Hippeutis, and Gyraulus.
Common water plants that harbor F. buski:
Water caltrop, Trapa
Water hyacinth, Eichhornia
Water chestnut, Eliocharis
Water bamboo, Zizania