“You don’t get to clean the turds out of the flower pot for a week”, isn’t really a good punch line. The conceptual continuity breaks with your punch line. If you put the words “chicken”, “pig”, and “cow” into the lead in to the joke it makes it all the more ridiculous; in fact, this is not even considered a joke, but a bit of word play, and at best a desperate try for a spoonerism-joke, and it just fails miserably at that.