Pet Columns, Office of Public Engagement, College of Veterinary Medicine at the University of Illinois at Urbana-Champaign

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What to Feed Wiley and Whiskers


Pet Column for the week of February 26, 2001


Office of Public Engagement
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
By Carrie Gustavson
Information Specialist

Poultry by-products, beet pulp, and corn gluten meal. That may not sound like what you want for dinner tonight, but that's what Max and Cody eat every day at my house. The label says it's good stuff, and Max's mouth is too full to complain. So how do you know for sure?

"When you are evaluating a pet food, what the label doesn't tell you is the quality of the ingredients," says Dr. Allan Paul, small animal Extension veterinarian at the University of Illinois College of Veterinary Medicine. "By-products" often include udders, lungs, and organ meats. That may be unappetizing to you and me, but it can be just as nutritious as meat or better for your four-legged friends.

Ingredients vary widely depending on the pet food, but the quality of the protein ingredients is most important. "A mixture of motor oil and leather can have the recommended amount of fat and protein, but it is completely non-digestible. Some proteins are more digestible than others. For example, a food based on a protein source such as chicken feet and beaks would be poorly utilized, because it's harder for a dog or cat to digest," says Dr. Paul.

Evaluating a pet food can be tricky, especially since there are thousands to choose from. In general, dry food will be more economical than wet foods, and cheaper foods may actually be more expensive than you think. That goes back to the quality of ingredients. If the food is poorly digested, you'll have to feed a lot more of it. With a more expensive, premium brand of food, you'll actually feed less because generally these foods are highly digestible.

To begin evaluating a pet food, start with the label. "You can get a rough idea of the contents by looking at the list of ingredients," says Dr. Paul. The ingredients are listed in order by weight. There is usually an 800 number to call if you have specific questions about the ingredients, too.

The label should also say that the diet is "complete and balanced." To make that claim on its label, a food must meet or surpass minimum nutritional requirements set by a governing body for pet food known as the Association of American Feed Control Officers, or AAFCO. Some pet food companies will actually test the food in research trials, which is even better. "If a company can respond to a client's question with scientific data, that's impressive," says Dr. Paul.

Often people think that since they take vitamin and mineral supplements, their pets should too. "A dog or cat has everything it needs in its diet, while people get to pick and choose. You can't transfer what we do or how you feed your kids to feeding a dog, cat, or puppy," says Dr. Paul.

That is especially true when it comes to calcium and vitamin D. People commonly think they should supplement calcium and vitamin D in a growing animal. "Excess calcium actually inhibits growth and can lead to developmental skeletal diseases," says Dr. Paul. Supplementation with the fat-soluble vitamins A and D can cause them to build up in the body and cause toxicity.

You really don't need to supplement a pet food diet with vitamins and minerals, but some owners want the "nutritional insurance" of supplementation. "There are all sort of interactions among different minerals. So if you supplement, give a balanced supplement. Don't just supplement calcium or vitamin D. Doing that will throw everything out of whack," says Dr. Paul.

Lastly, if your pet is healthy and happy, there is probably no need to change a diet that is working fine. If you do decide to try something different, change diets very gradually.

For more information about the nutritional wellness of your dog or cat, contact your local small animal veterinarian.