The cowboy

A cowboy rides into the western town and ties his horse up to the hitching rail outside the saloon.
Hops down, dusts himself off and walks around to the back of his horse. Then proceeds to lift the horses tail ands gives it a kiss on the butt.
The town sheriff is sitting on the porch of the saloon in a chair and says to the stranger,"that's a mighty weird habit you got there son".
The cowboy replies, "Not really sheriff. Three days in the desert and my lips are chapped . This stops me from licking them"