This goes for pets also. I know 230 has several articles on making your own dog food. But back to the original point. Chickens can free range for the majority of their feed, so can cows, goats and horses. But rabbits I fore see a problem. The occasional pig I raise won't be that much of a problem unless I try to raise more than one a year.
One of the more forgotten possible sources of meat that is total self sufficient is young pigeon. Pigeons if you set them up now, would be a source of at least some meat. They can be set up in a loft or attic now (or bird type house in the yard) let them get established before hand they will feed and water them selves.
Just a thought