Chances are, its scraps that wouldn't pass inspection for humans to eat!
So why should your dog have to eat it?
Here is a website
that lists ingredients of dozens and dozens of popular
and not so popular dog foods as well as store brands
and canned foods.
http://nav.webring.com/cgi-bin/navcgi?ring=rottie;id=238;go
100% free information to help dogs live a longer happier life!
Non-Commercial site. NOTHING FOR SALE !