Efficacy of triclabendazole against Fasciola hepatica and Fascioloides magna in naturally infected calves.

Twenty calves (8 to 12 months old), naturally infected with Fasciola hepatica and Fascioloides magna, were obtained from Brazoria, Tex. They were randomly allotted to 3 treatment groups. One group (6 calves) was given the carrier without drug, the 2nd group (7 calves) was treated with triclabendazole at 6 mg/kg of body weight, and the 3rd group (7 calves) was treated with triclabendazole at 12 mg/kg. All treatments were administered as a drench. Calves given triclabendazole (either dosage level) had a 100% reduction in F hepatica burden as compared with the untreated controls. Both treatment doses also appeared to have detrimental effect on F magna infections. Viability of all flukes was determined on the basis of movement, color, and tegumental integrity. Clinical toxic reactions were not observed in the treated calves.