there is one about the dogs who went to a party
and hung their assholes by the door, when a fire
broke out they did not have time to grab their own
on the way out...thus they are forever sniffing to
see if they can find their own again!

as for bawdy ballads, I am sure there are many.

Someone (Donovan?) did one about space travellers
with explicit details about how they take care of
bodily functions in outer space.
The Intergalactic Laxative offends some, if it is
offensive you are looking for...