Trial of Avermectin B 1a , Mebendazole and Melarsoprol against Pre-Cardiac Dirofilaria immitis in the Ferret (Mustela putorius furo)

Abstract

Avermectin B1a was active against the pre-cardiac stage of D. immitis in ferrets. The drug was given orally at 0.2 mg/kg on days 38-42 of infection. At necropsy, 5 1/2 mo. after inoculation, worms were almost totally absent from the hearts of these ferrets. The efficacy of melarsoprol against developing Dirofilaria, which was demonstrated in dogs by other workers, was demonstrated in ferrets given oral doses at 100 mg/kg on days 38-42 of infection. The reported efficacy of mebendazole was not evident in the ferret host in this study, probably because the treatment (100 mg/kg orally on days 38-42) was shorter and later than that reported for dogs.