The authors acknowledge CONCYTEC from Peru for the financial support.

Fasciolosis caused by Fasciola hepatica, is the most prevalent parasitic disease in dairy cattle from the northern region of Cajamarca, Peru. The control of this parasite is based on the use of Triclabendazole (TCBZ), a drug that has been used for more than fifteen years in this area. Recent studies, however, have reported a lack of clinical efficacy after treating dairy cattle. This research was aimed to determine the efficacy of TCBZ in a clinical trial. Eleven dairy cows all positive to F. hepatica identified by presence of eggs in feces, were treated with TCBZ (Fasinex® 10%) at 12 mg/kg body weight. Fourteen and thirty days after treatment, the animals were analyzed for F. hepatica eggs in their feces by the fecal egg count reduction test. The results found show an overall efficacy of 31.05% and 13. 63% (14 and 30 days post treatment, respectively). Furthermore, an in vivo efficacy ...