View All Slides

5 Nutritional Reasons That Cats Aren’t Just Small Dogs

T. J. Dunn, DVM
Updated: February 11, 2021
Published: August 21, 2015
Share this:
Cats are from Mars, Dogs and from Venus

By T.J. Dunn, Jr., DVM

In so many obvious ways, cats look, act, react, and respond differently than dogs. What is more difficult to see, however, is the metabolic and chemical differences between the two. Here are just a few of those amazing variations, and the reasons why you should pay close attention to what’s in your cat’s food. 

1. Cats are Carnivores

The cat is considered by scientists to be a strict carnivore, while the dog is considered to be an omnivore. Both species are in the Class Mammalia and the Order Carnivora, but here’s the difference: Cat’s cannot sustain its life unless it consumes meat in some form. Dogs, however, are able to survive on plant material alone - they do not have to consume meat. But always keep in mind that dogs do best and, by nature, are primarily meat-eaters.

2. Cats Can’t Produce Taurine

Taurine, an amino acid, is important for healthy the functioning of the heart, retina, bile fluid and certain aspects of reproduction. However, unlike in dogs, cats must eat preformed Taurine. That is why cat food must contain some source of Taurine, and in a proper amount.

3. Cats Can’t Produce Vitamin A

Also called retinol, Vitamin A is required at the cellular level by both cats and dogs. Cats process little or no enzymes that will break down the plant-produced carotenoids. They must eat preformed active Vitamin A (that is, Vitamin A that already has been converted from carotenoids to its active form). Dogs, meanwhile, have enzymes in the lining of the intestine that can break down plant carotenoids and convert these into active Vitamin A.

4. Cats Are Sensitive to Low Arginine Levels

A building block for proteins, Arginine is a vital amino acid for the body’s. Cats are extremely sensitive to even a single meal deficient in Arginine, and they are unable to make their own Arginine within their chemical factory. Dogs meanwhile, are not very sensitive to low levels of Arginine in their diets, and they produce enzymes internally that can aid production of Arginine.

5. Cats Can’t Produce Arachidonic Acid

If a dog eats enough proper fats, his body can produce Arachidonic acid. Cats, meanwhile, cannot produce this acid due to their liver’s inability to convert linoleic acid into Arachidonic acid. 

Rejoice in the Differences

So there you have it. The next time you admire a cat's unique personality and behavior, and watch the way they egocentrically carry themselves for anyone to see, remember ... hidden beneath that furry skin is another unique and vast universe. You can't see it, but it's there, silently following the rules of nature to sustain our unique and valued feline friends. And it's that complex chemical cosmos, working it's fantastic magic that prompts us cat lovers to say, truly ... cats are different!

Additional Slideshows