Sometimes I think our commercial pet foods are too refined, given the hideous (to us) things our pups will eat, given the chance. People will dump stripped deer carcasses and if in an accessible place our guys are proud and happy to arrive with a foot/hoof or leg joint, fresh or over-ripe. We have to find the remains quickly and dispose of them. They have never seemed to be ill after such an orgy but have been sickened by new dog food brands, if not introduced slowly.
One of my terrierists was a stray until picked up by the dog warden. He has nabbed chipmunks in the backyard and even a rabbit while I walked him on leash. Everything is devoured, hoof, hide, head and hair. The only thing that bothered him was the chipmunk he gulped down whole and then a bit later regurgitated on our bed.
Of course manufacturers put ingredients in pet food to make it palatable. Human food has the same problem...fats, sweets, salts and refined starches are just yummy, technically not addictive but look at our nation-wide weight problems.