If a light trail companion mule's daily ration is structured in thirds, what component occupies the one-third dedicated to bulk filler?

Answer

Beet pulp or low-sugar chaff.

A suggested structure for a light mule involves one-third bulk filler, such as plain beet pulp (soaked) or low-sugar chaff, to keep the hindgut occupied without adding starch load.

If a light trail companion mule's daily ration is structured in thirds, what component occupies the one-third dedicated to bulk filler?
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