Sawdust for Emergency Feeding of Dairy Cattle

Richard S. Adams, Penn State Emeritus, Professor of Dairy Science

Dairy farmers who are critically short of cash and normal forages, straw, or stover might consider feeding of hardwood sawdust or thin shavings in limited
amounts.  Some research done at several experiment stations including Penn State suggest that hardwood sawdust may be used at a level of 5 to 15% of the
total ration dry matter as a partial replacement for forage.

Do not use material that contains walnut since this may increase the incidence of founder, especially with horses.  Softwood sawdust is too poorly utilized
to warrant feeding.  Some problems with splinters in the GI tract or impaction may occur at higher levels of wood residue intake, or when it is fed for long
periods of over 90 to 100 days.  This can be kept at a minimum by putting the sawdust through a screen to remove slivers.

The digestibility of raw wood residue is relatively low compared to chemically treated wood in the form of cardboard boxes or newsprint paper.  It will,
however, help maintain normal rumen function in low forage, high concentrate rations.

Large breed dairy cows might be fed 2 to 6 lb of sawdust daily in a low forage, high concentrate ration, while dry cows or heifers probably should be
limited to 1 to 2 lb daily as a substitute for part of the forage that is fed.

Test the moisture level on non-kiln dried wood residue.  It may vary considerably.  The dry matter content of fresh or green sawdust may be only
40-50% while thoroughly air-dried or kiln dried material may be 85-88% dry matter.

The estimated nutrient content of hardwood sawdust or thin shavings is as follows on a dry matter basis:  crude protein 1.6%, acid detergent fiber 81%,
TDN .33%, NEL .300 Mcal/lb, calcium .11%, phosphorus .02%, magnesium .01%, potassium .05%, and sulfur .02%.  The feeding value of sawdust in a low forage
ration may be higher than indicated by its energy content, due to the contribution to the physical needs of the ruminant.  Preferably professional
help should be obtained in balancing all rations, especially those containing forage or roughage substitutes.

Source:  Richard S. Adams

Editor:  Charlotte Murphy
Ag Information Services -- News & Publications, Penn State
July 23, 1997
PENpages Number:  28902213