Canine's are not omnivores like humans, they are carnivores. They require animal based proteins and fats as energy sources, and have no nutritional requirement for carbohydrates. "Big Pet Food" comes up with "research" and BS explanations for putting crappy meats, by-products, chemical preservatives, grains and all other types of crap in their food. What they should say is we could care less about the health of your dog, we just want huge profit margins. Blindly following the lead of dog shows, vets, and pet retailers(who co incidentally benefit from selling crappy foods) Is the most idiotic(and unfortunately most common) excuse for animal abuse I have ever heard.