Forty-four male golden Syrian hamsters weighing approximately
120 g were used. Hamsters were obtained from the Animal Unit,
Faculty of Medicine, Khon Kaen University. Most of hamsters
were infected orally with 50 OVMC in 0.85% NaCl solution (Tables 1
and 2) using the gastric intubation method. After 1 to 2 months
post-infection, all hamsters were euthanized by diethyl ether inhalation
and the liver of each animal was removed and examined
for adult worms of O. viverrini. Those with positive findings were
counted and recorded. The experimental protocol was approved by
the Animal Ethics