Va. Code Ann. § 3.2-6001

The Commissioner, the Board, the State Veterinarian, and all other veterinarians within the Commonwealth shall use their best efforts to protect livestock and poultry from contagious and infectious disease. It shall also be the duty of the Commissioner, the Board, and the State Veterinarian to cooperate with the livestock and poultry disease control officials of other states and with the U.S. Department of Agriculture in establishing interstate quarantine lines and regulations so as to best protect the livestock and poultry of the Commonwealth against all contagious and infectious diseases.