Eurytrema spp in Ruminants
Pancreatic flukes have a thick body and are 8–16 mm long × 6 mm wide. They are parasites of the pancreatic ducts and occasionally of the bile ducts of sheep, pigs, and cattle in Brazil and Asia. Three species, Eurytrema pancreaticum, E coelomaticum, and E ovis are recognized. The first intermediate hosts are terrestrial snails (Bradybaena spp), and the cercariae are released onto herbage and ingested by grasshoppers (Conocephalus spp) or tree crickets (Oecanthus spp), which are the second intermediate host. After the animal ingests a metacercarial-infected grasshopper, the immature flukes excyst in the duodenum and migrate to the pancreatic duct, where they mature. The prepatent period of E coelomaticum in cattle is 3–4 mo.
There are no obvious clinical signs, but a general weight loss may occur in heavy infections. Dicrocoelium-like eggs can be demonstrated in feces. Light infections cause proliferative inflammation of the pancreatic duct, which may become enlarged and occluded. In heavy infections, fibrotic, necrotic, and degenerative lesions develop. These result in increased plasma concentrations of γ-glutamyl transpeptidase and AST. Losses are reported due to condemned pancreas, but the pathogenesis suggests an additional loss of production.
The control of intermediate hosts may not be practical. Treatment with praziquantel (20 mg/kg, for 2 days) or albendazole (7.5 mg/kg for sheep, 10 mg/kg for cattle) have reportedly been effective.