HAU DOLCE
A dog's calorie requirement
The number of kilocalories a dog needs per day. It is calculated from the formula RER = 70 x (weight in kg)^0.75 and then multiplied by a factor that depends on age, neutering and activity.
A dog's calorie requirement is calculated in two steps, and it is the same maths used by vet practices and the FEDIAF guidelines.
Step 1: RER, i.e. at rest
RER (Resting Energy Requirement) is the energy a dog needs when lying quietly:
RER = 70 x (body weight in kg)0.75
For a 10 kg dog: 70 x 100.75 = about 394 kcal.
Step 2: MER, i.e. real life
RER is multiplied by a factor matched to the dog:
- puppy up to 4 months: 3.0
- puppy over 4 months: 2.2
- neutered adult: 1.6
- intact adult: 1.8
- senior: 1.4
- weight loss: 1.0-1.3
Low activity lowers the factor by about 0.2, high activity raises it by 0.5. For our 10 kg neutered adult dog: 394 x 1.6 = about 630 kcal per day.
Step 3: from calories to grams
Divide the requirement by the calorie content of the food and multiply by 100. Wet food at 97 kcal/100 g: 630 / 97 x 100 = about 650 g a day. The same number of calories from dry food at 380 kcal/100 g is only about 166 g - and that is why wet and dry portions cannot be compared by eye.
What this formula does not cover
Pregnancy, lactation, metabolic diseases and working dogs. In these situations the vet sets the amount. The formula is a starting point, not gospel - check it against your dog's weight after two weeks.