Okla. Stat. tit. 4, § 85.2

Any domestic animal found running at large upon public or private lands in the State of Oklahoma, whose owner is unknown in the vicinity of the premises where found, shall be known as an "estray", and it shall be unlawful for any person, company or corporation or either of their employees or agents to take up an estray and retain possession of same, except as provided in this act.