Kloxerate Plus DC (Dry Cow) Presentation Kloxerate Plus Dry Cow is an off-white, stable intramammary suspension prepared under sterile conditions. Each single dose 4.5 g syringe contains: Cloxacillin (as benzathine salt) 500 mg Ampicillin (as the trihydrate) 250 mg in a long acting base with 3% aluminium monostearate. Ampicillin and cloxacillin are semi-synthetic penicillins derived from 6-aminopenicillanic acid.