No punchline.

(The punchline of these jokes is that there is no punchline. It's called a "Västgötaklimax". These are some of my favourites.)

Two cows were out flying. One of them then says to the other "you have a cinnamon bun in your ear".
"What?"
"You have a cinnamon bun in your ear."
"What?"
"You have a cinnamon bun in your ear."
"I can't hear you because I have a cinnamon bun in my ear."

Q: What's the difference between a horse?
A: All of its legs are of equal length, especially the right one.

Q: What's the similarity between an elephant?
A: None of them can ride a bicycle.

Two moose were sitting in a sauna. One of them then says "It's really hot in here". The other moose then answers "Yep".