Bimotrim Co Injection Dosage and administration 15 mg/kg (equivalent to 1 ml per 16 kg bodyweight) daily. Daily dosing should be repeated for two days after symptoms have resolved up to a maximum of 5 days. Cattle: By slow intravenous or intramuscular injection. Intramuscular injection is the preferred route of administration and should be given into the neck. Horses: By slow intravenous injection.