September 26, 2007

Swine specialist defines ideal size for feed particles

Lesser particle size of feed can improve the digestibility of the diet, according to a Kansas State University (K-State) animal scientist.

According to K-State Research and Extension swine specialist Bob Goodband, particle size should be maintained at approximately 700 microns with an optimal range of 650 to 750 microns. Larger particle sizes result in poor feed efficiency while smaller particle sizes increase the energy cost of grinding, susceptibility to ulcers, and problems with feeders' and bins' bridging, he said.

For every 100 microns that particle size is above the recommend range, the resulting cost for lost feed efficiency will be about US$0.65 (or 65 cents) per pig, he said.

"For example, suppose you haven't checked your particle size recently, and it has crept up to 1,000 microns. If you reduce that particle size to 700 microns, that will save you almost two dollars for every finishing pig marketed," he noted.

Goodband said producers can ensure proper particle size by performing routine maintenance, such as changing hammer mill screens or turning hammers. Producers should also adjust the gap between rolls and re-groove rolls in roller mills regularly.