Basic nutrition for Dogs

Pet nutrition principles for feeding dogs continue to evolve. An example of how far we've come concerns what we veterinarians, 30 years ago, used to call "All Meat Dogs." These pathetically sick and dying dogs were coming in to clinics all over the United States, thin, weak, with hair loss and metabolic imbalances as a direct result of eating a nationally advertised "All Meat" canned dog food.

Nearly everyone at that time thought that because dogs were carnivores (they're technically omnivores) that "all meat" diets must be the best thing for them! We know now that dogs cannot survive if fed 100% meat for extended periods.

FATS
Fats provide the most concentrated source of energy in the diet. They also supply the fatty acids that are important building blocks for important substances and essential to maintaining normal, healthy cells. Along with protein, fats contribute to a diet’s palatability, plus aid absorption of the fatsoluble vitamins A, E, D and K.

Like protein’s essential amino acids, fat has its own essential fatty acids (EFAs): linoleic acid, linolenic acid and arachidonic acid. Because they make up an important part of every cell, they are also required by animals. Linoleic acid is the source of omega-6 fatty acids, and linolenic acid is the source of omega-3 fatty acids. According to Strombeck, animals need more omega-6 (linoleic acid) than omega-3 fatty acids for health.

CARBOHYDRATES
Although dogs do not need carbohydrates because their bodies can get energy from protein and fats alone, carbohydrates that can be broken down by the digestive system and converted to glucose can also be a source of energy. (Carbs can be the main caloric source in some dog foods.)

Carbohydrates in the form of whole grains can furnish iron, minerals and fiber as well as other beneficial nutrients. Since cooking determines starch digestibility, and therefore its availability, starches need to be well cooked; otherwise, they tend to ferment in the large intestine. Carbohydrates can be found in vegetables and fruit, which also supply minerals, fiber, antioxidants, phytochemicals and some protein.

VITAMINS 
Fresh, wholesome food provides your dog (as well as you) with the best source of vitamins, organic substances required for normal functioning of the body. They are also important in the conversion of calories to energy. Ackerman points out that they are needed in only small amounts: “All of the vitamins needed by your dog on a daily basis could be provided by a fraction of a teaspoon.” (See chart on for ingredient sources for vitamins and minerals.)

MINERALS 
Minerals are inorganic nutrients that make up less than 1 percent of a dog’s body weight but are essential to many important functions, such as growth and strong bones and teeth. They are classified as either macrominerals or microminerals. It is important to note that two of the macrominerals, calcium (the most abundant mineral in the body) and phosphorus, must be in balance and given in correct proportions (the ideal calcium:phosphorus ratio is between 1:1 and 2:1). Microminerals (also known as trace minerals) serve very important functions as well. Balance is critical with all minerals because they interact; too much of one can interfere with the absorption of another.

BOTTOM LINE 
If you elect to feed your dog commercial food (and most of us do), here’s what to look for and what to avoid when you’re standing in front of a shelf of carefully designed bags, cans, pouches or boxes.

• High-quality named animal proteins should be the first ingredient, and, ideally appear more than once as top items on the ingredient list. Note that whole meat is made up of a lot of water (up to 75 percent), so if a whole meat is listed as the first item, the food might not contain an equal amount of meat by weight unless there is another whole meat, or a specifically named meat meal (chicken meal, for instance, which is about 10 percent water). Avoid foods that use generic “meat” meal; the actual type of meat needs to be named: lamb meal or chicken meal, for example. Fat should also come from named source, avoid generic “animal” fat.
• Whole fruit, vegetables and whole grains which contain the entire grain kernel. For example, rice rather than rice flour or bran. Refined grain products, gluten and mill runs should be avoided.
• Natural preservatives like tocopherols (Vitamin E) and Vitamin C, or antioxidants like rosemary extract.
• Avoid: All by-products (from meat, grain or any other source); added sweeteners (which are usually listed as grain fragments); artificial preservatives such as BHA, BHT, ethoxyquin, propylene glycol; and artificial flavors or colors.

Dry-Matter Basics
When you compare different types of foods — canned, kibble, etc. or simply different brands — you need to keep in mind the moisture content so you can compare like to like. Use the dry-matter basis.

First, establish the amount of dry matter by subtracting the percentage given for moisture from 100 percent. If the moisture is given as 10 percent, the food’s dry-matter content is 90 percent.

Next, convert the protein found in the Guaranteed Analysis statement to a drymatter basis by dividing its percentage by the amount of dry matter (calculated in the previous step). For example, if the protein is given as 26 percent, it converts to 28 percent on a dry-matter basis (26 divided by 90). If the moisture level had been, say, 30 percent, the dry matter content would have been 70 percent and protein would have been 37 percent (26 divided by 70).

You can do similar calculations for fat and fiber after converting their percentages to a dry-matter basis.

TREATS
Although treats are usually given in small portions (or ought to be!), make sure that you pay the same high level of attention to what’s in them as you do for all of your dog’s food. Look for organic, wholefood ingredients, including named meats, whole grains, lots of good fruit and/or vegetables and natural, food-based sweeteners (if they are used at all) — applesauce, honey or molasses, for example. Avoid by-products, artificial coloring, artificial flavoring and artificial preservatives. Look for individual portions that are easy to break into smaller bits.

Treats are often high in calories, so factor them in when thinking about your dog’s overall food intake. It is recommended that “treat substitutes” make up no more than 5 to 10 percent of a dog’s diet. If the calorie count isn’t listed on the label, find out what it is before giving them to your dog. Contact the manufacturer for calorie information if need be. 

Vitamin/mineral supplements for 99.9% of dogs are not required if the dog is on a high quality diet.In fact, providing extra calcium to large dogs on a proper diet will do harm. It is incorrect to give extra calcium just because "it's growing up so fast."

Dogs frequently develop allergies to corn, wheat, soy and other foods. Allergies are manifested usually by dry, itchy skin; reddened, swollen ears; itchy face and chin; compulsive licking of the paws. (Caution! These signs also are present when a dog has sarcoptic mites, so these parasites must be considered in any dog that seems to have a food allergy.) Vomiting and or diarrhea, meanwhile, may result if the dog develops food intolerances. Food allergies and intolerances can be a challenge for the veterinarian to properly diagnose.

Many dog food recipes fall short in certain nutrients, especially iron, copper, calcium, and zinc. Even some recipes created by veterinarians don't measure up. The University of California, Davis, School of Veterinary Medicine tested 200 recipes, many written by vets. The researchers found most of the recipes were short on some essential nutrients.

Your pet needs protein (animal meat, seafood, dairy, or eggs), fat (from meat or oil) and carbohydrates (grains or vegetables). He also needs calcium (from dairy or an ingredient such as egg shells), and essential fatty acids (from certain plant oils, egg yolks, oatmeal, and other foods).

And if that's not enough to consider, if your dog has a health problem, he may need a special diet. You may need a pet nutrition expert to create custom recipes.

Should I Feed Canned or Dry ... or Both?

If dog owners had to choose one or the other, canned food or dry food, they should choose the dry. Canned food is generally 75% water, so 75% of your purchase price is going toward a non-nutritive ingredient that you can readily obtain from your own water faucet. Plus, there is an advantage to oral hygiene in the friction of the dry dog food, helping to keep the gums and teeth healthier than if the dog were eating only canned food.