In vivo assessment of Closantel ovicidal activity in Fasciola hepatica eggs

BACKGROUND: Fasciolasis is a zoonotic parasitic disease caused by Fasciola hepatica. Closantel is a flukicide and has been shown to have an efficacy in vivo e in vitro against mature and immature stages, does not exhibit ovicidal activity in vitro and the ovicidal effects in vivo at present are undetermined. Egg hatch assay (EHA) is a laboratory tool used to determine a given parasite's resistance to extant drug therapy remains a safe and reliable technique. In the present work the EHA was used to evaluate in vivo the ovicidal activity of Closantel on fluke eggs. METHODS: Sheep parasitized with liver flukes (Cullompton strain) were treated with Closantel (10 mg/kg bw) (oral and subcutaneous) stunned and exsanguinated at 12, 24, y 36 hs. Post treatment (pt). F. hepatica eggs were collected from bile. Eggs obtained of sheep without treatment were used as control. After a period of incubation (25 °C, 15 days in dark environment), hatching was induced for two hours of exposure to li...