If a zoologist was handed the question “What do dogs eat?” the very first place they would look would look for would be studies of stomach or scat of wild and free roaming dogs. Fleming et al. (2001) that investigated the cadavers of 13,000 wild roaming domestic dogs, dingoes and hybrids of the two (making up the largest portion of the study). These dogs were culled in the outback of Australia. They found the stomach contents to contain 97% animal matter with the 3% vegetation coming from “smaller prey where the stomach contents could not be shaken free”. If the question is “what do dogs eat?”, the answer most certainly is meat.
Every independent biology book on the matter agrees. Dogs love it and thrive on it, and the fresher the better.
Need more convincing? Just look at those teeth! Ever see an omnivore with teeth like that? They’re not for attacking a wheat field, and that’s just the outside body parts. Inside they’re all about meat digestion, with a gut like battery acid and a short, rapid digestive system. They can even make their own carbohydrates (sugar) from protein and fat (a process called glycogenesis, something only carnivores can do). Nor do they have any amylase in their saliva for digesting carbohydrates in their saliva. Another trait of carnivores. Hence they do not require carbohydrates (plant food) in their diet. There is nothing omnivorous about this animal at all, biologically speaking.
Unfortunately meat is expensive, which is not ideal when making cheap, cereal based dog food. So over the last few decades dry food companies, via our veterinary universities thanks to extremely generous financial donations, have started re-teaching us that the dog not only is not only an omnivore (a meat and plant eater) but that he actually does better on a low meat-low protein diet, that is high in cereal/carbohydrates. A lucky coincidence that it also happens to be much cheaper to produce!
But Dogs eat Fruit and Vegetables!
Dogs will certainly eat fruit and vegetables – but only if fed to them by humans when they are pups. Due to human interference some pet dogs will scavenge or beg for fruit or vegetable matter now and again. However Kuo (1967) showed that if a dog is reared on a more normal meat based diet they will not eat vegetable matter later on. They can be reared on an all vegetable (or all dry food) diet and they will eat that every day too later on, leading owners to believe that their dog “loves vegetables”, a quirk that is readily exploited by dry food manufacturers. That the dog will eat vegetables or dry food is beyond doubt but this does not make it good for them. They are scavenging carnivores, total opportunists. If foods are experienced when young they are mentally tagged as safe and eaten for ever more. However just because they eat it does not make it good for them, after all how many things do we eat and know we shouldn’t!
And even if they are eating vegetables, all one has to do is look at their reaction to meat to know what they really want.
Kuo, Z. Y. (1967). The dynamics of behaviour development: An epigenetic view. New York: Random House.