Colorado Revised Statutes Title 35. Agriculture § 35-48-103. Inferior bulls or rams

(1) It is unlawful for any person, firm, or corporation to permit any inferior bull over the age of one year or any inferior ram over the age of two months to run at large in this state. Any bull shall be considered an inferior bull that is not registered or eligible for registration as a purebred animal.

(2) Any person permitting cows of which he is the owner or agent of the owner to run at large upon the public ranges of this state shall furnish during breeding season at least one registered purebred bull of one of the recognized beef breeds, not less than eighteen months of age, for every twenty-five head of cows or fraction thereof over ten head so permitted to run at large in this state. No owner or agent of the owner shall permit any jersey, holstein, guernsey, ayrshire, or other bull not registered or eligible for registration as one of the recognized beef breeds to run at large in this state under any pretense whatever, and should any such bull break through any enclosure surrounded by a lawful fence, the owner of such animal shall be liable for all damages occasioned by such trespass.

(3) Any person violating any of the provisions of this section commits a civil infraction.