If you have even a small number of acres, you can pasture poultry. If you have a little bit more, you can pasture sheep, goats, and cows. Many people feel that raising animals on pasture is superior to feed. The meat and eggs have superior nutrition (it's been tested) and the animals live lives more similar to how their genetics intended them to live.
I've raised chickens on pasture for both eggs and meat. For raising broilers on pasture, I wasn't happy with the Cornish Rocks. They don't seem to like to move too far from their feeders. This year we are going to try some Freedom Rangers - I'll report back! This breed is supposed to be meant for eating grass,weeds and bugs. My layers are great foragers so I'm hopeful.
Learn the basics of pasturing poultry.
Photo © Flickr user Brian Forbes