Bacitracin is a mixture of related cyclic polypeptides produced by a member of the Bacillus subtilis group (24). Unlike most antibiotics its use is limited in oral administration and typical methods of application are by adsorption through the skin where the drug degrades the bacterial cell wall in Gram positive bacteria by blocking the dephosphorylation of the C55-isoprenyl pyrophosphate (25), an important molecule in the process of building the bacterial cell wall. Its main application is for fowl animals such as chickens in the form of an antibiotic drug and no MRLs have yet been established for this drug.