Protein is best known for supplying amino acids to build hair, skin, nails, muscles, tendons, ligaments, and cartilage. It also plays a main role in hormone production.
The protein in dog foods can be supplied by animal sources, plant sources or a combination of the two. High-quality animal-source proteins contain all of the essential amino acids dogs need, while a single plant-based protein might not contain adequate amounts of some essential amino acids.
Common animal-based protein sources used in pet food include chicken, lamb, fish, and beef.
Even though they are often fed plant-based diets, dogs are not herbivores. While dogs are technically considered to be omnivores—animals that eat both animal- and plant-based foods—they should be treated primarily as carnivores to better fulfill their specific nutritional requirements.
Dogs are members of the Canidae family. This family also includes the wolf, coyote, fox, and jackal. The ancestors and relatives of today's common dog hunted animals and ate them as a means of survival.
The body structure of domestic dogs is similar to that of their ancestors and relatives and is ideal for eating prey. Dogs have the enlarged carnassial teeth after which carnivores are named. Their gastrointestinal tract is simple and does not have the capacity to digest large amounts of plant products.
Animal-based proteins help dogs achieve optimal health.
As your dog matures, his body functions change. He might have decreased immune-system function, deterioration of skin and coat quality, and more frequent intestinal problems. So it makes sense that what a mature dog eats might also need to change.
Throughout a dog's life, a process called peroxidation occurs. This is a normal process the body uses to destroy cells that outlive their usefulness and to kill germs and parasites, but this process also can destroy or damage healthy cells. As a dog ages, the damage caused by peroxidation accumulates and, in turn, increases the risk of certain problems such as infections.
Antioxidants are naturally occurring components in the body (but also can be acquired through diet). They help maintain overall health by neutralizing the peroxidation process of cellular molecules.
Research sponsored by IAMS™ found that dogs fed a diet rich in antioxidants such as vitamin E had improved immune responses and vaccine recognition. This might be especially important for mature/senior dogs, because IAMS research has found that, as dogs age, immune responses can decrease.
Eating a complete and balanced diet with omega-3 fatty acids, such as those found in vitamin-rich fish oils, also helps rejuvenate dry skin and develop a healthy, lustrous coat.
Aging dogs might have higher numbers of unfavorable bacteria and lower numbers of beneficial bacteria in their intestines, which can result in clinical signs of gastrointestinal problems (such as diarrhea). A diet with a moderately fermentable fiber source such as beet pulp can help maintain intestinal health. Beet pulp provides energy for the cells lining the intestine and promotes proper stool formation.
Different dogs show signs of aging at different times, and much of this variation is associated with size. Larger dogs generally appear mature/senior sooner than smaller dogs. The table below can show you when your dog should start a mature diet with a food such as IAMS ProActive Health™ Mature Adult.
Dog Weight and Transition to Mature/Senior Foods
| Weight Range | Age to Begin Transition |
|---|---|
| More than 90 lbs | 5 years |
| 51 to 90 lbs | 6 years |
| 21 to 50 lbs | 7 years |
| Up to 20 lbs | 7 years |