I beleive these laws were found unconstitional in a federal court realatively recently and all state laws regarding the private activity of two concenting adults have been repealed. Might have my wires crossed, but I do remember reading some news item to that effect.
This is the actual text from the Michigan Criminal Code 2005 that I carry on duty and use to enforce the laws.
750.158 Sexual delinquant person
Elements:
(1) Commit the abominable and detestable crime against nature, sodomy
(2) Either with mankind or with any animal
Penalty:
A Class F felony against public order, punishable by imprisonment in the state prison not more then 15 years, or if such a person was at the time of the said offense a sexually delinquent person, may be punishable by inprisonment in the state prison for an indeterminate term, the minimum of which shall be 1 day and the maximum of which shall be life.