Macaulay Culkin took part in a donkey show in Mexico this weekend ... but it was bestiality-free.
Mac and R&B singer Har Mar Superstar were in Tijuana for a concert. They posted this pic just before going on stage, teasing the surprise guest who was riding a zonkey.
For those unfamiliar -- zonkeys are donkeys painted to look like zebras ... a long-standing TJ thing.
The concert was a hit, though judging from the photos a little on the weird side. Then again, compared to what strippers do on stage in TJ this was Hannah Montana territory.