When selecting the best food for your dog’s regular diet, you should consider the caloric content of the food you choose.  If the food you select for your dog is energy-dense, and your dog is a couch potato, you may have to cut the daily ration considerably to prevent your dog from getting fat.  Some dogs respond to forced dieting with begging, counter-surfing, and garbage-raiding.  If your dog is one of these, you may have to seek out a high-fiber, low-calorie food one that may not necessarily contain the highest-quality protein or fat sources on the market to keep your dog feeling contentedly full without getting fat.

Dogs exhibit a wide range of energy requirements. You may have to seek out a higher- or lower-calorie food based on the following attributes that can affect your dog’s energy needs:

Activity level

The more a dog exercises the more energy he needs to consume to maintain his condition; it’s that simple.

Growth

Growing puppies have higher energy requirements than adult dogs. A food with a higher protein level, but a moderate (not high) fat level is ideal. Obese puppies are far more prone to degenerative joint disease especially in large and giant breeds than puppies with a normal or slim physique.

Age

The age at which a dog becomes a senior citizen varies from breed to breed, with larger dogs considered geriatric at earlier ages. Older dogs typically require fewer calories to maintain their body weight and condition, partly because they tend to be less active than younger dogs.

Source: “How to Choose Dog Food,” By Nancy Kerns, Whole Dog Journal

Environmental conditions

Dogs who live or spend much of their time outside in severe cold temperatures need from 10 percent to as much as 90 percent more energy than dogs who enjoy a temperate climate. The thickness and quality of the dog’s coat, the amount of body fat he has, and the quality of his shelter have direct effects on the dog’s energy needs.

Illness

Sick dogs have increased energy needs; it takes energy to mount an immune response or repair tissues. However, dogs who do not feel well also tend to be inactive, which lowers their energy needs.

Reproduction

A pregnant female’s energy requirement does not increase significantly until the final third of her pregnancy, when it may increase by a factor of three.

Lactation

A nursing female may require as much as eight times as much energy as a female of the same age and condition who is not nursing.

Neutering

It is generally accepted that neutered (and spayed) dogs have reduced energy needs. However, there are actually no studies that conclusively prove that neutered dogs require fewer calories simply as a result of lower hormone levels. It has been suggested that these dogs gain weight due to increased appetites and/or decreased activity levels.

Other individual factors

Other factors that can affect a dog’s energy requirement include its temperament (nervous or placid?) and skin, fat, and coat quality (how well he is insulated against weather conditions).