Rabbits, Quail and Worms - the rabbits produce meat and their manure falls down into the pen below, which contains coturnix quail and worms. The worms feed on the rabbit and quail manure, and, in turn, the quail eat maggots and worms and produce meat and eggs. What a cool system!
It may not be the BEST farm task, but when it needs to be done, these tips will come in handy when you decide to delve into butchering chickens. http://www.attainable-sustainable.net/butchering-chickens/