What is the formula for resting energy requirement (RER) in dogs?

• A. 60 × BW^0.75
• B. 70 × BW^0.75
• C. 70 × BW
• D. 70 × BW^0.5

Answer: (B)

Resting energy requirement is the number of calories a dog needs at rest to maintain basic bodily functions in a comfortable environment. Metabolic rate scales with body size in a way that isn’t linear, following a 3/4 power relationship with body weight. The widely used formula reflects this by multiplying the body weight (in kilograms) raised to the 0.75 power by 70. So the resting energy requirement is 70 × BW^0.75, with BW in kilograms. This matches observed energy needs across different dog sizes.

For example, a 10 kg dog would have an RER of about 70 × 10^0.75 ≈ 390 kcal/day. The other options don’t fit this scaling: using 60 instead of 70 underestimates RER, using a linear BW relationship overestimates energy needs in larger dogs, and using BW^0.5 underestimates due to too small an exponent.