Reminds me of the children's story about the guinea pigs sent on British Rail, that bred en route to their destination.The station master demanded payment for hundreds of pigs..
"I don't care if they be Guinea Pigs or other pigs - 'cause pigs is pigs!"
Edit: I remembered it as a British tale, but it seems it originates in the US:
http://en.wikipedia.org/wiki/Pigs_Is_Pigs