By Dr. Hans H. Stein

December, 2010

It is well known that corn needs to be ground to be effectively utilized by pigs. For many years it has been common practice to recommend grinding to an average particle size between 650 and 700 microns. This particle size was based on research showing that if grain is ground to a smaller particle size, then problems with ulcers in pigs may increase.

There is, however, also research showing that energy and nutrient digestibility will increase if particle size is reduced below 650 microns. Because of this increase in nutrient and energy digestibility, less feed is needed to produce one pound of gain if grain particle size is reduced. Newer research has indicated that feed conversion may be improved by 3 to 5% if corn particle size is reduced from 650 to 450 microns. There is, therefore, substantial savings associated with reducing grain particle size and many producers are now grinding to an average particle size of 450 to 500 microns.

Problems with ulcers do not seem to be as much of an issue any longer because most diets contain more fiber than they used to because of inclusion of DDGS in the diets. Inclusion of more fiber in the diets reduces the risk of pigs getting ulcers so inclusion of fiber sources such as DDGS or wheat middlings in the diets reduces the risk of pigs getting ulcers. But there are also producers who do not use DDGS who have reduced the particle size of the grain without experiencing problems with ulcers.

With the increasing costs of feed ingredients, it is necessary to look at all opportunities for reduction in feed costs – and reduction of the grain particle size is an easy way to start saving.