Frothy bloat on pasture is most commonly associated with which type of forage?

• A. Legume forages.
• B. Grass only.
• C. Silage.
• D. Grain-based diet.

Answer: (A)

Frothy bloat from grazing happens when gas produced in the rumen gets trapped in a stable foam, which the animal cannot eructate away. Legume forages, such as alfalfa and clover, are most likely to cause this because they are highly leafy and rapidly fermentable, and they contain components that promote foam stability. When animals graze lush, young legume pastures, they ingest large amounts of material that readily forms foam in the rumen, so gas becomes trapped and the stomach distends.

Grass pastures tend to produce less of this stable foam, so they’re less commonly associated with frothy bloat on pasture. Silage or grain-based feeds aren’t pasture grazing and involve different bloat dynamics, so they aren’t the typical pasture-related cause.