Code of Federal Regulations Title 43. Public Lands:  Interior § 43.4750.2–1 Health and identification requirements

(a) An individual determined to be qualified by the authorized officer shall verify each excess animal's soundness and good health, determine its age and sex, and administer immunizations, worming compounds, and tests for communicable diseases.

(b) Documentation conforming compliance with State health inspection and immunization requirements for each wild horse or burro shall be provided to each adopter by the authorized officer.

(c) Each animal offered for private maintenance, including orphan and unweaned foals, shall be individually identified by the authorized officer with a permanent freeze mark of alpha numeric symbols on the left side of its neck. The freeze mark identifies the animal as Federal property subject to the provisions of the Act and these regulations by a patented symbol, the animal's year of birth, and its individual identification number. The authorized officer shall record the freeze mark on the documentation of health and immunizations. For purposes of this subpart, a freeze mark applied by the authorized officer is not considered a brand.