Topics:
Animal Nutrition, Animal Refresher
Metabolic Water from Protein Oxidation
Metabolic water produces by oxidation of 1 g of protein is:
- 1.07 g
- 0.40 g — Correct Answer
- 0.56 g
- None
Explanation:
Correct Answer: 0.40 g
The oxidation of 1 gram of protein produces 0.40 g of metabolic water — the least of all major macronutrients because protein has a lower hydrogen-to-carbon ratio and part of the hydrogen is incorporated into urea (urinary loss).
Metabolic Water — Complete Reference Table
| Substrate | Metabolic Water per gram | Note |
|---|---|---|
| Fat | 1.07 g | Highest — richest in hydrogen |
| Glucose/Sugar | 0.60 g | |
| Starch | 0.56 g | |
| Protein | 0.40 g | Lowest — hydrogen lost as urea |
Why Protein Gives Least Metabolic Water
- Protein contains nitrogen → forms urea → nitrogen and associated hydrogens leave via urine
- This means less hydrogen is available for water formation compared to carbohydrates and fats
- Metabolic water comprises 5–10% of total water intake of domestic animals
Why Other Options Are Wrong
- 1.07 g → metabolic water from fat oxidation, not protein
- 0.56 g → metabolic water from starch oxidation
- None → incorrect; 0.40 g is the standard established value for protein
📚 About this Topic — Animal Nutrition
This multiple choice question is from Animal Nutrition, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Nutrition to strengthen your preparation.
