Why did the ox get kicked out of the herd?
Because it wasn't being an ox, it was being a butt-ox...!
Butt-ox
Explanation
Explain Bear
Listen here, kiddo. The joke is playing on "butt" (meaning behind) and "butt-ox", a portmanteau that sounds like buttocks. This is funny to the comedic genius who wrote the joke because oxen don't have butts, you uncultured swine.
Anonymous
haha