In terms of tissue distribution of O. viverrini metacercariae in
fish, our results showthat themajority ofmetacercariaewere found
in the body muscles followed by the base muscles of the pectoral
fins, and rarely in tail and dorsal fins, but none at all in the ventral
or anal fins. Already Vichasri et al. (1982) reported in their earlier
work that the most of O. viverrini metacercariae were found in the
body muscles and only small numbers in the base muscles of the
fins. Although Harinasuta and Vajrasthira (1960) reported 90–100%
of O. viverrini metacercariae in the base muscles of the pectoral fins,
at that time not much attention was paid for the body muscles as
the site of infection. The body muscles of the cyprinoids suppose to
be the preferential site of infection of O. viverrini metacercariae.