Necessary Nutrients
Fortunately, it's easy to find out whether your dog is getting the correct amount of nutrients. Health and safety regulations do require that dog foods list their ingredients and their nutritive values on their labels. You can learn a lot about the quality of the food by looking carefully at the label on the package.
You're looking for some basic factors that must be present for sound nutrition: proteins, carbohydrates, vitamins, minerals, and fats. The ingredients are listed in descending order by weight — that is, how much of the ingredient is actually in the product. Therefore, if a pure meat source like chicken, beef, or lamb is right up there at the top, you can be sure you're buying a protein-rich food.
Proteins
Proteins are present in all kinds of meat and meat by-products, such as chicken, lamb, beef, or chicken meal. These are the best sources of protein for your dog. Many foods use vegetable proteins such as soy. These are harder for your dog to digest, so although you will invariably find them in his food, make sure they aren't a sizable source of that food's ingredients. A dog's need for protein varies depending on his age, size, and activity level. You'll see that puppy foods have high levels of protein, whereas senior foods contain lower levels.
Dogs need a total of twenty-two amino acids, but their bodies can only synthesize twelve of them. Essential amino acids include arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Good health correlates to the consumption of the proper amino acids.
Carbohydrates
Carbohydrates, which are necessary for energy, also make up some of the primary ingredients in dog food. Their sources are typically rice, corn, or some other grain, though more and more frequently vegetables such as sweet potatoes are being used as well. Wheat and soy can sometimes trigger an allergic reaction in dogs, which is why more and more formulas use rice as their starch. Some dogs aren't affected at all, however, so it's always wise to monitor your dog's overall health.
Vitamins and Minerals
Dogs need vitamins and minerals to keep their bodies functioning, just as we do. A lack of iron means not enough hemoglobin to pick up red blood cells in the lungs, which means a less energetic dog. A lack of vitamin E can result in brittle skin. Vitamin C has been called a wonder vitamin for its curative powers. Several commercially available foods on the market now already add special vitamins to the food to compensate for certain conditions. One of the most popular is the addition of glucosamine and chondroitin in foods for senior dogs, as these vitamins promote joint health.
If you're not sure what a particular vitamin's function is and you note that there's a lot of it in your dog's food, do some research and, most important, observe your dog for the potential side effects (hopefully good ones).
Fats
Fat is a necessary part of any dog's (or animal's) diet. Fat is what keeps the skin supple and the coat shiny. Too little fat, and your dog will end up with a dry, brittle coat and dry skin; too much fat, and you'll end up with an obese, well-greased dog. Fat is extremely palatable to dogs, so manufacturers need it for nutritive and taste values. This can lead to problems with storage, as fats tend to oxidize and go rancid when exposed to air or heat. They must be preserved in order to hold.
What about preservatives in the food?
Manufacturers use preservatives to maintain freshness, taste, and texture. In the 1980s, dog breeders raised concerns about the adverse effects of a common chemical preservative, ethoxyquin. Ethoxyquin and the chemicals BHA and BHT were thought to contribute to numerous health problems. Now these are rarely used, though it's important to check for them. Instead, most manufacturers use natural preservatives — tocopherol, a form of vitamin E, and ascorbic acid (vitamin C).
Canine nutrition is a hot topic. The bottom line is how well your dog does with the food you feed her. If you select a premium brand and feed according to the guidelines in this chapter, your dog should show all the signs of being healthy: clear, shiny eyes; soft, supple coat; pink gums; normal stool and urine; and appropriate energy level. If she doesn't seem healthy to you, speak with your veterinarian and research a dietary change.
All-Important Water
No discussion of what to feed a dog is complete without mentioning water. This is a nutrient as important to dogs as it is to other living things. Dogs can go longer without food than they can without water. To stay hydrated, and to cool off, dogs need a constant supply of fresh, clean, cool water.
Don't let your dog drink out of the toilet. This is not a substitute for a water bowl, and in fact could be contaminated with bacteria that could seriously harm your dog.
It's absolutely necessary to leave out a clean bowl of water at all times for your dog. Dogs can't tell you when they're thirsty, so it's vital that you leave water for them at all times. That way, when they're thirsty, they'll drink. Change the water in your dog's bowl a few times a day, and clean the bowl thoroughly once a day. Attention to the water bowl may also alert you to any changes in how much — or little — your dog is drinking, which can be an indication of a more serious medical condition.
