General Prohibition. A person may not conduct a livestock exhibition or exhibit livestock without first complying with the requirements of this chapter for the prevention of contagious or infectious disease. A person may not enter or show livestock at any exhibition if the livestock has a contagious or infectious disease. Ringworm. A person may exhibit livestock showing signs of ringworm only if the exhibitor possesses a certificate from a veterinarian stating that the affected livestock: Has been under appropriate ringworm treatment by that veterinarian for at least 21 days before entering the exhibition site; and Is no longer contagious to other animals. Rabies Vaccination. A person may not show livestock at any petting zoo unless all exhibited animals in the petting zoo, 105 days or older, are vaccinated against rabies as provided in COMAR 10.06.02, unless there is no rabies vaccine licensed and approved by the U.S. Department of Agriculture for that animal species.