A long-lasting persistent, uniform film-forming skin protecting germicidal composition provides a long-lasting persistent barrier film when applied to skin. The compositions have particular utility as barrier teat dips for protecting cows against mastitis. A barrier film-forming agent is selected from the modified or hydrolyzed polysaccharides, particularly a hydrolyzed or modified starch, such as dextrin and maltodextrin. The barrier film-forming agent is stably solubilized in a solvent that dries to form the long-lasting persistent uniform film over the animal skin. The compositions also contain antimicrobial agents that fight against microbes that manage to penetrate the protective barrier film. Particularly, advantageous is that all the materials used are safe food additive and cost effective over the traditional barrier film forming agents.