Bad Joke for a Saturday

A cowboy rides his horse slowly into town, pulls up in front of the saloon, dismounts and ties the horse to the hitchin rail. He then walks arround behind the horse, raises it tail, and plants a kiss squarely on the old pooper then ambles into the bar.
After a bit, the bartender says, "Cowboy, we all couldn't help but notice what you did out there, would you be so kind as to tell us why?"
The cowboy replies, "I have chapped lips."
"How in thunder will kissing your horses ass help chapped lips?'
"keeps me from lickin em."