Comparison of a combination of oxfendazole and fenthion versus ivermectin in feedlot calves.

A trial involving 6,169 feedlot calves was conducted under commercial feedlot conditions in western Canada to compare the relative efficacy of treatment with a combination of oxfendazole and fenthion (O/F) versus ivermectin (I) with respect to the outcome variables, final weight, gain, days on feed (DOF), dry matter intake (DMI), average daily gain (ADG), dry matter intake to gain ratio (DM:G), and morbidity, mortality, and carcass grade parameters.There were no significant differences (p >/= 0.05) between the treatment groups for final weight, gain, DOF, DMI, ADG and DM:G. In addition, there were no significant differences (p >/= 0.05) in the carcass grading parameters between the treatment groups. The bovine respiratory disease (BRD) relapse rates, the overall mortality rates, and the cause specific mortality rates were not significantly different (p >/= 0.05) between the treatment groups. The BRD treatment rate in the O/F group was significantly lower (p </= 0.05) than in the I group, but this difference was not economically important.These data indicate that a combination of oxfendazole and fenthion is comparable to ivermectin with respect to performance, animal health, and carcass grade parameters.