Efficacy of febantel paste against naturally acquired gastrointestinal nematodes of cattle. 
Twenty calves with naturally acquired gastrointestinal nematode infections were assigned to 10 replicates of 2 calves each and were treated with febantel paste (5 mg/kg of body weight, PO) or an equivalent volume of paste vehicle (control calves).  Adverse reactions were not observed after febantel treatment.  At necropsy, gastrointestinal nematode counts in febantel-treated calves, compared with control calves, were reduced by over 99% for all major species except Trichuris discolor, counts of which were reduced by only 69%.  Counts of gastrointestinal nematode eggs in feces of febantel-treated calves were reduced by 100% after treatment.