Mich. Comp. Laws § 317.62

Sec. 2. Any person or persons who at any time hereafter, in any part of the state of Michigan, without the consent of the owner or caretaker of any enclosure within which fur-bearing animals are kept for breeding purposes, and on the fence of which enclosure are kept posted notices forbidding trespassing on the premises where the said animals are kept, and plainly discernible at a distance of not less than 25 yards therefrom, shall pass within the said fence or such enclosure or climb over, break or cut through the same for the purposes of entering the said enclosure, or for any other purpose whatsoever, shall be guilty of an offense and liable to the penalty hereinafter provided.