An antimicrobial composition and a method for administering the antimicrobial composition through the water or feed of livestock, wherein the antimicrobial composition is made up of lysozyme and various other agents that act synergistically with lysozyme, such as, dried egg powder, albumen, a sequestering agent and /or a lantibiotic. The composition is used to inhibit the growth of, and diseases and epidemiological significant effects caused by, Clostridium perfinigens , E, coli and Salmonella , in the gut of livestock. More particularly, the antimicrobial composition and method relate to a feed additive that can be administered to poultry and /or swine through their feed. The use of such a feed additive may also inhibit other enteric pathogens that may be present in the gut of livestock.