1. What is Resting Energy Requirement (RER)?

The Resting Energy Requirement (RER) represents the number of calories a pet needs at rest in a thermoneutral environment. It's the baseline energy requirement before accounting for activity level, life stage, or health status.

2. How Does the Calculator Work?

The calculator uses the RER equation:

Where:

• \( Weight \) — Body weight in kilograms
• 70 — Constant multiplier
• 0.75 — Exponential factor for metabolic scaling

Explanation: The equation accounts for the non-linear relationship between body weight and metabolic rate, with smaller animals having higher metabolic rates per unit of body weight.

3. Importance of RER Calculation

Details: RER is the foundation for determining a pet's daily caloric needs. It's used to calculate maintenance energy requirements (MER) by applying appropriate multipliers based on life stage, activity level, and health status.

4. Using the Calculator

Tips: Enter the pet's weight in kilograms. For accurate results, use the pet's current weight (not ideal weight) unless specifically calculating for weight loss.

5. Frequently Asked Questions (FAQ)

Q1: Is RER the same as daily caloric needs?
A: No, RER is the baseline requirement. Daily needs are typically 1.2-2.0× RER depending on activity level, life stage, and health status.

Q2: How do I convert my pet's weight from pounds to kilograms?
A: Divide pounds by 2.205 to get kilograms (e.g., 10 lbs ÷ 2.205 = 4.535 kg).

Q3: Does this work for both dogs and cats?
A: Yes, the RER calculation is the same for both species, though their maintenance energy multipliers may differ.

Q4: What about puppies/kittens or pregnant pets?
A: These life stages require energy multipliers above RER (typically 2-3× RER for growth and reproduction).

Q5: How often should I recalculate my pet's RER?
A: Recalculate whenever your pet's weight changes significantly (e.g., ±10% of body weight).