Question

Which of these is used to prevent the urea poisoning in ruminants?

• A. HCOOH
• B. \(\text{CH}_3\text{COOH}\)
• C. \(\text{CH}_3\text{COCOOH}\)
• D. \(\text{C}_2\text{H}_5\text{COOH}\)

Hint:

Ammonia (\(\text{NH}_3\)) is uncharged and easily crosses membranes.
Ammonium (\(\text{NH}_4^+\)) is charged and cannot cross membranes.
Acidifying the rumen with acetic acid (\(\text{CH}_3\text{COOH}\)) traps ammonia in the non-toxic \(\text{NH}_4^+\) form.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Urea is widely used as a non-protein nitrogen (NPN) source in ruminant feed.
If consumed in excess, rumen urease rapidly converts urea into ammonia (\(\text{NH}_3\)), raising rumen pH and leading to systemic ammonia toxicity (hyperammonemia).

Step 2: Detailed Explanation:
To treat or prevent urea poisoning, the alkaline rumen environment must be acidified.
- Adding a weak organic acid such as acetic acid vinegar (\(\text{CH}_3\text{COOH}\)) lowers the rumen pH.
- Under acidic conditions, toxic free ammonia (\(\text{NH}_3\)) is protonated into non-volatile, non-absorbable ammonium ions (\(\text{NH}_4^+\)).
- This protonation prevents the rapid absorption of ammonia across the rumen wall into the bloodstream, resolving the systemic toxicity.

Step 3: Final Answer:
The substance used to prevent urea poisoning is \(\text{CH}_3\text{COOH}\), corresponding to option (B).