更新1:
I don't see the difference. There's no reason why we couldn't keeps dogs and cats in farms the same way we do other animals. And their meat also has plenty of protein and iron, like any meat.
更新2:
http://www.youtube.com/watch?v=4lVKakE5vtw
更新3:
@Naiomi - Pigs and cows are not wild animals. They once were, like dogs and cats, but were domesticated thousands of years ago. Also dogs and cats would not be pets if they were on a farm. They would be livestock.