Anthelmintic treatment of prepatent stephanuriasis with flubendazole, levamisole and disophenol and the effects on liver-specific serum enzymes.

Haematological parameters and liver specific serum enzymes were examined in pigs during the first 12 weeks of liver migration of larvae following experimental infection with 1000 infective Stephanurus dentatus larvae. No significant changes in total red blood cell counts, packed cell volume, or haemoglobin content were observed. Total white blood cell counts and circulating eosinophils rose rapidly from days 5 and 19 after infection, respectively. Treatment with a mixture of levamisole (LEV) at 10 mg/kg and flubendazole (FLU) at 50 mg/kg in feed four weeks after infection halted the leucocyte response and returned values to normal in two weeks. Disophenol (DIP) at 15 mg/kg subcutaneously restricted the leucocyte response but it was only terminated following FLU treatment alone on day 61. No effects of S dentatus or either anthelmintic treatments on liver specific serum enzymes glutamate dehydrogenase, sorbitol dehydrogenase or gamma-glutamyl transpeptidase were found. Animals killed seven, 26 and 54 days after treatment showed significant resolution of fibrotic liver lesions after LEV + FLU but not after DIP. We conclude that LEV + FLU is an effective treatment for prepatent stephanuriasis but that liver damage is insufficiently traumatic to release sufficient enzymes into serum to be pathognomonic or to assess anthelmintic efficacy.