In Vitro Organic Matter Digestion

In Vitro Organic Matter Digestion

The procedure is “two-stage”: (1) incubation of a sample with rumen microorganisms for 48 h followed by (2) 44 h incubation with acid-pepsin. Results are expressed in percentage units, meaning the percentage of OM which was “digested” or disappeared. Estimated quality of forage is indicated by the IVOMD value rather than by the yield per unit land area of digestible OM (DOM). If it is desired to calculate DOM yield, use the following equation:


Failure to multiply DM yield by BOTH OM concentration and IVOMD is an error.

Suggested Text Statement: In vitro organic matter digestion (IVOMD) was performed by a modification of the two-stage technique (Moore and Mott, 1974).


Moore, J. E., and G. O. Mott. 1974. Recovery of residual organic matter from in vitro digestion of forages. J. Dairy Sci. 57:1258-1259.