Okla. Admin. Code § 325:20-1-21
The Official Veterinarian must be a graduate veterinarian and licensed to practice in the State of Oklahoma. He or she shall recommend to the Stewards any horse that is deemed unsafe to be raced, or a horse that it would be inhumane to allow to race. He or she shall supervise the taking of all specimens for testing according to procedures approved by the Commission except in those cases provided for in Rule 325:20-1-22. He or she shall provide proper safeguards in the handling of all laboratory specimens to prevent tampering, confusion, or contamination. All specimens collected shall be sent in locked and sealed cases to the laboratory. He or she shall have the authority and jurisdiction to supervise the practicing licensed veterinarians within the enclosure. He or she shall report to the Commission the names of all horses humanely destroyed or which otherwise expire at the meeting and the reasons therefore. No Official Veterinarian shall directly treat or prescribe for any horse scheduled to participate during his/her term of appointment at any recognized meeting except in an emergency or for the administration of a diuretic to facilitate the collection of a urine sample, either case of which shall be immediately reported to the Stewards. The Official Veterinarian shall place horses on the Veterinarian's List and may remove from the List those horses which, in his/her opinion, can satisfactorily compete in a race.
Okla. Admin. Code § 325:20-1-21