An apparatus and method for applying an antimicrobial agent to whole or split animal carcasses include a closed or essentially closed chamber for limiting the escape of antimicrobial agent to the environment during antimicrobial treatment of the carcass. In one embodiment, a series of carcass cabinet panels moves in line with the passing animal carcass and forms an enclosure around the carcass by means of panels closing ahead of and behind the carcass. In another embodiment, the direction and spray pattern of positively charged aerosolized antimicrobial particles in a carcass cabinet is controlled by attracting the particles to preselected negatively charged regions within the carcass cabinet.