1. What is RER?

RER (Resting Energy Requirement) is the amount of energy required by an animal at rest in a thermoneutral environment. It represents the basic caloric needs for maintaining vital body functions.

2. How Does the Calculator Work?

The calculator uses the RER equation:

Where:

• \( BW \) — Body weight in kilograms (kg)
• 0.75 — The metabolic exponent for most mammals
• 70 — The coefficient derived from empirical data

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: Accurate RER estimation is crucial for determining appropriate nutritional requirements for pets, especially during illness, recovery, or weight management programs.

4. Using the Calculator

Tips: Enter body weight in kilograms. The value must be valid (weight > 0). For best results, use the most recent and accurate weight measurement available.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between RER and MER?
A: RER (Resting Energy Requirement) is the baseline energy need, while MER (Maintenance Energy Requirement) includes activity factors and is typically 1.2-1.8 times RER for normal pets.

Q2: Can I use this calculator for all pets?
A: This formula is primarily designed for dogs and cats. Other species may require different coefficients or equations.

Q3: How often should I recalculate my pet's RER?
A: Recalculate whenever your pet's weight changes significantly, or at least every 3-6 months for growing animals and every 6-12 months for adults.

Q4: Are there limitations to this equation?
A: The equation may be less accurate for very young, very old, or critically ill animals, and for breeds with extreme body compositions.

Q5: Should RER be used for weight loss programs?
A: RER is often used as a starting point for weight loss programs, but veterinary guidance is recommended as individual needs may vary.