For people with a dog or a cat, you may have wondered if you can get away with feeding cat food to your dog or dog food to your cat. Cat owners especially have probably thought this, since cat food is often more expensive than dog food.
After all, the two foods look essentially the same, except that cat food seems to be chopped up (or molded) into smaller pieces. Is there any difference?
The answer is: yes, there is quite a bit of difference. Although you can probably get away with feeding dog food to your cat or vice versa, it’s not a good idea on a long-term basis.
A major difference is the protein makeup of the two foods. Cat food consists of about 30% protein, whereas food for dogs typically falls into the 20-25% range. While this may not seem like a significant difference, it can definitely add up over time.
The reason for this difference goes back to the evolutionary heritage of the animals. Cats are pure carnivores who survive almost exclusively on meat. Even during their domestication process, they mostly fed on mice, rats, and birds. This is why you will often see cats chasing and playing with these critters.
Dogs, on the other hand, aren’t pure carnivores. Like humans, they are omnivores. A dog’s dietary requirements are actually very similar to a human’s dietary requirements. Before the development of commercial dog food, dogs almost always ate the scraps of food that their owners gave them. So dogs need more vegetable and grain products than a cat does.
Cat food also contains taurine and vitamin A, while not all dog food does. Although every living creature needs these essential nutrients, dogs and humans can synthesize them from other compounds. Cats, on the other hand, have traditionally gotten these nutrients directly from the flesh of other animals, so if they don’t eat food that has been fortified with them, problems can arise. Hair loss, tooth decay, heart problems, and even blindness have been observed in cats that were given a diet of exclusively dog food.
Cat food also contains more arachidonic acid and niacin. These are compounds that dogs can also synthesize from a variety of foods, but cats must get them from meat. These nutrients are important to both animals, but cats need a bit more of them.