Model of Cellulose Disappearance from the Rumen

Abstract

Lignin concentration in fiber influences the extent of in vivo ruminant digestion, but increasing lignin content during digestion does not slow rate of digestion. Digestion of Lignified fiber proceeds as if the cellulose is of two definable components—potentially digestible and indigestible. Indigestible cellulose disappears from the rumen by passage only. Passage is proportional to that present and may be expressed as a linear semilog function of time. The potentially digestible cellulose disappears by both passage and digestion. These two simultaneous rates sum to one rate which is proportional to that present and may be expressed as a linear semilog function of time. The fractional digestion of the potentially digestible component in the rumen is given by the digestion rate over the sum of digestion rate and passage rate. © 1972, American Dairy Science Association. All rights reserved.