Herd. One or more animals that are:
(1) Under common ownership or supervision and are grouped on one or more parts of any single premises (lot, farm, or ranch) or
(2) All animals under common ownership or supervision on two or more premises which are geographically separated but on which animals have been interchanged or had direct or indirect contact with one another.
9 CFR § 55.1
Accredited veterinarian. A veterinarian approved by the Administrator in accordance with part 161 of this chapter to perform functions specified in subchapters B, C, and D of this chapter.