Dog Food Ingredients

Nutritional requirements and dog food

Pet-nutrition experts say that the best dog food is made from top-grade ingredients like meat, whole grains and vegetables. What you don't want is a lot of filler as the primary ingredients; these are items that have less nutritional benefit.

According to reviews, better-quality dog food results in a healthier coat, fewer digestive problems and firmer stools. Because your dog will absorb more nutrients from better-quality dog food, less will be passed as waste.

Dogs love meat, and they need protein. Unlike cats, which need high amounts of protein and no carbohydrates at all, dogs need a diet that contains as much as 50 percent carbohydrates. Still, experts say meat should be the first ingredient, followed by healthy carbohydrate sources such as potatoes or more absorbable grains like rice.

If you've read any dog food labels, you might have noticed the term "byproduct." Meat byproducts consist mainly of animal parts that are not used for human consumption, such as bones, organs, blood, fatty tissue and intestines. If a label says "chicken byproduct," all the parts must come from chicken; the same goes for lamb, beef, etc.

There are two schools of thought when it comes to byproducts in dog food. Some say that because a dog in the wild would eat the entire animal when killing prey, including skin, organs and bones, some amount of byproduct in dog food is just fine. What you don't want, say reviews, is unidentified byproducts, often listed as "meat byproducts." Experts say this could include zoo animals, road kill and what's often referred to as 4-D livestock (dead, diseased, disabled, dying). Meat by-products can include euthanized dogs and cats. In 1990 the American Veterinary Medical Association and the FDA confirmed that some pet food companies were using the bodies of euthanized pets as byproducts in their foods. It turns out that this practice wasn't widespread but limited to small rural rendering plants and a few other assorted links in the pet food manufacturing chain. For these reasons, reviews that do approve of some byproducts in pet food say that dog owners should look for specific origin, such as chicken byproduct or lamb byproduct.

Note that in poultry-based dog foods, the term "byproduct" is used to identify byproduct meals. However, in other types of dog food, byproduct meal can be labeled as "meat and bone meal" (MBM) or even "beef and bone meal." This type of labeling is legal, but clearly misleading.

The other -- and prevailing -- school of thought is that byproducts should be avoided entirely, and that a dog's diet should contain meat, vegetables and absorbable grains. These critics say that it's simply too hard to know what exactly is included in byproducts, and some say that these unwanted animal parts may contain bacteria or even parts from cancerous animals. MBM used in cattle feed is suspected of being an agent in the spread of bovine spongiform encephalopathy (also known as mad cow disease).

Similarly, there's a low-quality ingredient called animal digest, which is the dry or liquid byproduct of the meat rendering process. Experts say that although there is meat content in animal digest, it's of little nutritional value because it is not very digestible.

In dry foods the listing of meat at the top of an ingredient list can be misleading, because meat has a high water content that is removed when processed into dry pet food. However, so-called "meat meal" is meat with the water removed, and finding it high up in the ingredient list is a good indication of a high-protein dry food. Again, beware of foods that contain meat and bone meal or beef and bone meal, as those are low-quality ingredients.

The quality of the carbohydrate sources also matter. According to information from wildlife advocacy organization Born Free USA, dogs can absorb almost all the nutrients from white rice, but grains like oats, flour and wheat have almost no nutritional value for them. Corn products aren't very valuable either, and peanut hulls have no value at all. Glutens are another group of ingredients that experts say don't provide much nutritional value to dogs, and are a particular concern since 2007's massive recall of pet foods tainted by contaminated wheat and rice gluten from China.

Dog food companies are making moves to get away from using artificial preservatives in dog food. Chemicals used as preservatives, like BHA, BHT and ethoxyquin, have been under scrutiny, and many companies are switching to natural preservatives like vitamin C (ascorbate) and vitamin E (tocopherols). Naturox, which is made from natural ingredients, is also gaining in popularity. Reviews say natural preservatives are much safer. Ethoxyquin has been of particular concern to some because it is also used to preserve certain ingredients -- mainly fishmeals -- before they reach the pet food maker and hence is not included on ingredient lists.