Calves ( n = 6 calves/group ) were assigned to receive marbofloxacin SC in the neck at 1 of 3 dosages ( 2 mg/kg , q 24 h for 6 days [ regimen 1 ] ; 4 mg/kg , q 48 h for 6 days [ regimen 2 ] ; and 4 mg/kg , q 24 h for 3 days [ regimen 3 ] ) .