Topics:
Animal Physiology, Animal Refresher
Blood Volume as Percentage of Body Weight
Blood volume of an animal is generally ______ % of its body weight:
- 8% — Correct Answer
- 4%
- 12%
- 6%
Explanation:
Correct Answer: 8%
The total blood volume of an animal is approximately 8% of its body weight.
Body Fluid Compartments
- Total body water (TBW): 60–70% of body weight
- Total blood volume: 8% of body weight
- Plasma volume: 5% of body weight (55% of total blood volume)
- Formed elements (RBCs + WBCs + Platelets): 45% of total blood volume
- Intracellular fluid (ICF): 40% of body weight
- Extracellular fluid (ECF): 20% of body weight
Practical Example
- A 500 kg Holstein-Friesian cow has approximately 500 × 0.08 = 40 litres of blood.
- Plasma volume = 500 × 0.05 = 25 litres.
Measurement of Blood Volume
- Plasma volume is measured using Evans Blue Dye (T-1824).
- ECF is measured using inulin.
- TBW is measured using heavy water (deuterium oxide, D₂O) or tritium oxide.
📚 About this Topic — Animal Physiology
This multiple choice question is from Animal Physiology, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Physiology to strengthen your preparation.
