Topics:
Animal Nutrition, Animal Refresher
VFA Responsible for Milk Sugar Production
VFA responsible for milk sugar (lactose) production is:
- Acetate
- Propionate — Correct Answer
- Butyrate
- None
Explanation:
Correct Answer: Propionate
Propionate (Propionic acid) is the gluconeogenic VFA — it is the main precursor for glucose synthesis in ruminants, and glucose is subsequently used for lactose (milk sugar) synthesis in the mammary gland.
VFA Functions — Summary
| VFA | Rumen Proportion | Key Role |
|---|---|---|
| Acetate | 65% | Milk fat synthesis |
| Propionate | 20% | Gluconeogenesis → Lactose (milk sugar) synthesis |
| Butyrate | 10% | Ruminal epithelium energy; ketone body formation |
Propionate — Key Facts
- Propionate is the main gluconeogenic precursor in ruminants (Table 19: Glucose ← Propionate)
- High concentrate diets increase propionate → higher milk yield
- ATP from propionate oxidation: 17 ATPs per mole
Why Other Options Are Wrong
- Acetate → responsible for milk fat synthesis; not milk sugar
- Butyrate → converted to β-hydroxy butyrate (ketone body) by ruminal wall; not glucose precursor
- None → incorrect; propionate's gluconeogenic role is well established
📚 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.
