Forage Particle Size

Dairyland provides Forage Particle Size analysis using the ASAE S424, which is the standard analysis that the Penn State Particle Separator is based upon (Lammers, 1996).  ASAE S424 was originally developed by researchers at the University of Wisconsin to evaluate the particle size of chopped forages.  This laboratory analysis features mechanical operatation, use of as-fed samples, and very large surface area, all of which enhance the repeatability and accuracy of the measured values (Mualfair et al., 2010).  Since its adoption by the American Society of Agriculture Engineers, this analysis has become the standard by which forage harvestor manufacturers measure particle length.

50 Corn Silage samples analyzed by ASAE S424 and the Penn State Particle Separator at Dairyland

The Forage Particle Size Report includes the following measurements:

The forage particle size separator divides a sample into 6 distinct particle size classes by shaking the sample through screens that vary in both width and depth of openings.

Interpretation

Researchers from the University of Wisconsin recommend the following for lactating dairy rations:

Sources
Lammers, B.P., D.R. Buckmaster, and A. J. Heinrichs. 1996. A simple method for the analysis of particle sizes of forage and total mixed rations. J. Dairy Sci. 79:922-928.
Maulfair, D.D., G.I. Zanton, M.Fustini, and A.J. Heinrichs. 2010. Effect of feed sorting on chewing behavior, production, and rumen fermentation in lactating dairy cows. J. Dairy Sci. 93:4791-4803.