VFA with Maximum Absorption Rate
Which VFA (Volatile Fatty Acid) has the maximum absorption rate from the rumen wall?
- Acetate
- Propionate
- Butyrate — Correct Answer
- All are absorbed equally
Correct Answer: Butyrate
The order of VFA absorption rate from the rumen wall is: Butyrate > Propionate > Acetate
Butyrate (4C) is the most lipid-soluble of the three main VFAs and is preferentially absorbed by rumen epithelial cells, where it is converted to β-hydroxybutyrate before entering the bloodstream.
Mechanism
VFA absorption occurs by passive diffusion — only the undissociated (protonated) form crosses the lipid membrane. Lipid solubility increases with chain length: Butyrate > Propionate > Acetate.
VFA Quick Reference
- Ratio: Acetate 65% : Propionate 20% : Butyrate 10%
- ATP: Acetate 10, Propionate 17, Butyrate 25
- Milk fat → Acetate; Glucose/Lactose → Propionate; Ketone bodies → Butyrate
📚 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.