It looks as if Slate reporter Jackson Landers finally read the many books published by Ann Martin about what is in dog food [May 6, Smarter Living, "A Dog-Eat-Dog World, Literally"]. I first read Martin's book "Food Pets Die For" more than 10 years ago and immediately put my dogs on organic dog food.
I often tell people to not feed commercial dog food to their pets because of what is in it. Vets have had trouble putting dogs to sleep because they have been eating the drug that puts them to sleep all of their lives. The drug does not break down during the cooking process. Neither does the mad cow prion.