Colo. Rev. Stat. § 40-9-106
Every common carrier in this state must transport livestock from the initial point of shipment in this state to the point of destination in this state at an average rate of speed of not less than ten miles an hour and within such time, from the hour of loading at the initial point to the hour of arrival at the destination, that the point of destination shall be reached in not more than one-tenth as many hours as there were miles required to be traveled in the transportation of such shipment; except only that necessary stops of reasonable duration for feeding purposes, when required by the length of the journey, or necessary and imperative delays caused only by an act of God or inevitable accident shall not be computed in determining such minimum requirements as to speed.
C.R.S. § 40-9-106