The present invention is directed to an activator composition comprising copper sulfate, zinc sulfate, sodium chloride, and ammonium sulfate, for the activation of an anti-microbial composition. The resulting activated anti-microbial composition is used for the treatment of an infectious disease of a foot of an animal, particularly for the use of ungulates. Benefits of using the activator composition, either alone or in conjunction with other anti-microbial compositions, include the reduction of copper deposited into the environment from anti-microbial treatments, extended use of an anti-microbial composition, and maintenance of low levels of infectious diseases of the feet of animals.