Untreated wood

Numerous feeding trials and laboratory experiments have shown that the nutrients in untreated wood are essentially unavailable to farm animals with the exception of a few less lignified hardwood species. The new concept of feeding cattle on high-grain rations has increased the possibility of using wood residues like sawdust and chips as the roughage component. Experiments have shown that sawdust is an effective roughage substitute when it constitutes up to 15% of the total ration. Cattle compensate for the lower energy of sawdust-diluted feed with higher intake. Some sawdusts - poplar is an outstanding example - are partly digestible by cattle. The in vitro digestibility of spruce sawdust is nil, of oak sawdust 5% and of poplar sawdust 30%. 

As % of dry matter

DM

CP

CF

Ash

EE

NFE

Ca

P

Ref

Pinewood, Germany

1.0

69.8

0.5

0.4

28.3

359

Digestibility (%)

Animal

CP

CF

EE

NFE

ME

Ref

Pine sawdust

Sheep

0.0

11.9

42.6

6.7

0.38

268

References

268, 359, 427