The following is an excerpt from Petfinder.com’s The Adopted Dog Bible
Most high-quality, complete and balanced dog foods are formulated to meet the nutritional requirements of normal, healthy dogs. Pet parents can look for a statement on the bag or can indicating that the product meets the nutritional requirements set by the Association of American Feed Control Officials (AAFCO), which allows the manufacturer to place the “complete and balanced for all life stages” claim on the label.
The AAFCO, along with the Food and Drug Administration (FDA) and the Department of Agriculture (DOA), plays a role in regulating the pet food industry. The AAFCO is responsible for identifying ingredients that can legally be used in pet food, establishing nutrient profiles, providing protocols for feeding trials to ensure product safety, and enforcing the regulations, standards, and laws regarding the manufacture, distribution, and sale of pet food.
Meeting AAFCO standards is one element a pet parent can take into consideration when determining that a brand or kind of dog food is healthy and safe; but even with these safeguards in place, problems do occur.
In addition, many canine authorities believe that some commercial dog foods are loaded with unnecessary ingredients and potentially dangerous chemicals, fillers, and byproducts. It’s important to take your time researching and reading about the different pet foods available and reading their ingredient lists carefully. (See Reading Dog Food Labels for more information.)
The Whole Dog Journal, a monthly publication full of information on natural dog care and training, publishes an annual review of dry and canned dog food, which is a great resource to consider when choosing what to feed your dog.
Let’s start by looking at the three main types of commercial dog foods, which are wet, dry, and soft/moist. They differ in a number of characteristics, including moisture content, palatability, nutritional benefit, and cost.
Wet Food. All wet food, which is sold in cans, contains 75 to 80 percent water (look for “moisture content” on the label), 8 to 15 percent protein, and 2 to 15 percent fat. Because of the high moisture content, dogs can eat more of this type of food without gaining weight.
Canned foods offer the highest palatability when compared to dry and soft/moist products (which is good for finicky eaters, toothless dogs, and for hiding medications), but wet food also has the highest cost per serving. Once a can is opened, it must be refrigerated to retain freshness, and many dogs will not eat their food very cold. To solve this problem, most people will warm subsequent meals.
Dry Food. Dry food comes in bags (as with most things, the larger the bag, the bigger the cost savings) and contains 18 to 40 percent protein, 7 to 22 percent fat, 12 to 50 percent carbohydrates, and about 10 percent moisture.
Dry dog food comes in different shapes, sizes, and colors, because dogs discern the texture, density, size and shape of the food, and the way a food feels in the mouth contributes to its relative palatability. One advantage of dry dog food is that it acts like a toothbrush, helping to remove plaque and tartar from a dog’s teeth while he eats. In addition, it stays fresh longer than soft/moist and canned food once the package is opened.
Soft/Moist Food. This type of food is usually sold in boxes that contain single-serving pouches. Soft/moist dog food contains approximately 15 to 25 percent protein, 5 to 10 percent fat, 25 to 35 percent carbohydrates, and approximately 30 percent water.
Soft/moist food is highly palatable and convenient to serve and store (perfect for travel), although it is more expensive than dry food. However, soft/moist food should not be fed as a substitute for dry or wet food, as it is high in sugar and salt.