A very long time ago in the late 1800s people killed the pigs to get the bladders to make a rugby ball. If you don't know what a bladder is, it is something that holds the pigs pee.
Do you know how the people made a ball? They grabbed the bladder from the pig and they blew it up with their lips. It was smelly so they used the stem of a clay pipe as a tube to blow it so they did not blow it up with their lips.