Frothy bloat is characterized by gas trapped in stable foam that cannot be eructated. Which option best reflects that description?

• A. Gas trapped in stable foam (mixed with rumen contents)
• B. Gas escapes normally by eructation
• C. No gas is produced
• D. Rumen distension without foam

Answer: (A)

Frothy bloat happens when the gas produced in the rumen becomes trapped inside a stable foam that cannot be eructated. That foam forms a persistent layer around the rumen contents, preventing the gas from escaping as a normal belch. Because the gas is enclosed in foam, the rumen distends and the animal is unable to relieve the pressure. The best match to this description is the idea that gas is trapped in stable foam.

The other ideas don’t fit this situation: gas escaping normally by eructation would relieve the gas, no gas being produced contradicts the premise of gas formation, and rumen distension without a foam layer points to a different form of bloat (free-gas bloat) rather than frothy bloat.