Comparative test of the efficacy of fenbendazole and mebendazole in the control of equine Strongyles

Abstract

The efficacy of Fenbendazole and Mebendazole against strongyle infections was evaluated in a controlled trial using 23 naturally infected mares. Such equines, aged from three to eighteen years, cross-bred and field-raised, were distributed in three groups, each with similar pre-treatment fecal egg counts. Group A: 8 received a single dose of granulated Fenbendazole at the level of 7,5 mg/kg, with the fodder. Group B: 8 received a single dose of granulated Mebendazole at the level of 2,000 mg/ animal, with the fodder and Group C: 7 being left as untreated controls. Worm differential larval counts were made on feces at: -12, - 8, - 4, 0, 1, 2, 3, 11, 18, 25, 31, 45 and 60 days of treatment. Fecal samples were collected at 24, 48 and 72 hours posttreatment. Alfortia edentata, Delafondia vulgaris, Strongylus equinus and small strongyles were recovered from such fecal samples. A significant reduction in the mean output of strongyle eggs posttreatment occurred in the Groups A and B. This reduction was larger and more lasting in Group A than in Group B.