1. What is Respiratory Exchange Ratio?

The Respiratory Exchange Ratio (RER) is the ratio between the amount of carbon dioxide (CO₂) produced and oxygen (O₂) consumed during metabolism. It provides insight into the type of fuel (carbohydrates vs fats) being metabolized.

2. How Does the Calculator Work?

The calculator uses the RER equation:

Where:

• \( VCO_2 \) — Carbon dioxide output (mL/min)
• \( VO_2 \) — Oxygen consumption (mL/min)

Explanation: The ratio indicates which macronutrients are being metabolized - values near 1.0 suggest carbohydrate metabolism, while values near 0.7 suggest fat metabolism.

3. Importance of RER Calculation

Details: RER is important for understanding metabolic status, nutritional requirements, and energy expenditure in dogs. It's particularly useful in veterinary nutrition and critical care.

4. Using the Calculator

Tips: Enter VCO₂ and VO₂ in mL/min. Both values must be positive numbers measured under standardized conditions.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal RER value for dogs?
A: Normal resting RER in dogs typically ranges between 0.7-1.0, depending on diet and metabolic state.

Q2: How does RER differ from RQ?
A: RER (Respiratory Exchange Ratio) is measured at the mouth, while RQ (Respiratory Quotient) reflects cellular metabolism. They are equal during steady-state conditions.

Q3: When should RER be measured?
A: RER is most meaningful when measured after the dog has rested and is in a post-absorptive state (typically 4-6 hours after eating).

Q4: What affects RER values?
A: Diet composition, exercise, stress, and metabolic disorders can all affect RER values.

Q5: How is RER used clinically?
A: In veterinary medicine, RER is used to estimate resting energy requirements and guide nutritional support.