Under cooked food meat and eggs!!!
My dogs, (see my profile picture) are fed only raw food, raw meat, bones, eggs, fish. They eat whole chickens etc,(all their meet is human grade meat) after seeing what rubbish they put in commercial pet food we decided never to feed them that rubbish again. since we went over to feeding a far more natural diet, tour dogs have excelled! they are calmer, their coats have improved, their teeth never need cleaning and our little Shi-tzu 9 (now 10 years old) that has had a skin complaint all his life is now free of it, it cleared up within a few weeks of going over to raw food, our Irish Wolfhounds are pedigree dogs and regularly shown and win prizes.
And guess what, feeding human grade raw meat etc is actually cheaper!! :)
I think commercial dog food should be added to that list!!