(1) When a pen, alleyway or any section of a market becomes filthy, or is considered deleterious to animal health, it must be ordered closed and be placarded by a representative of the Montana department of livestock, animal health division. The placard must read: "CLOSED. THIS PEN UNFIT FOR YARDING LIVESTOCK. BY ORDER OF THE MONTANA DEPARTMENT OF LIVESTOCK, ANIMAL HEALTH DIVISION." The use of such pen, alleyway or section of yard must be discontinued until it has been put in satisfactory sanitary and physical condition, and the placard removed by a representative of the Montana department of livestock, animal health division.