Ceftiofur is an antibiotic of the cephalosporin type (third generation), licensed for use in veterinary medicine. It was first described in 1987. It is marketed by pharmaceutical company Zoetis as Excenel, Naxcel, and Excede and is also the active ingredient in that company's Spectramast LC (lactating cow formulation) and Spectramast DC (dry cow formulation) product.