Summary
Results showed that the performance of an individual grinder did not change from batch to batch as long as the grinding process was replicated the same batch after batch. A majority of smaller producers (56%) use a screen that is a ¼ inch or larger in their hammer mills when grinding feed. Their results indicate average particle sizes are larger than the target of 700 microns. The results of this trial show that hammer mills with a 3/16-inch screen or less perform best in achieving a target of 700 microns.
Kansas State Research has shown that every 100-micron reduction in particle size will yield a 1.2% improvement in feed efficiency. This equates to about $0.45 per pig with present feed prices. The economic impact to Ohio producers that participated in the project who had particle sizes greater than 800 microns is approximately $198,000 in lost efficiency. Keep in mind that feed prices are relatively low and that higher feed prices would have a much greater economic impact on producers.
The challenge for producers and commercial feed mills will be the need to continuously monitor micron sizes and make the necessary adjustments to maintain the desired final micron size. General maintenance and upkeep are important factors that determine micron size and these should be performed routinely. Prolonged use will lead to excessive wear and require replacement of screens, hammers and rollers to maintain feed quality targets. Through the implementation of a weekly or monthly monitoring system for micron size on feed produced, producers and feed mills could capture increased efficiencies and improve profit potential
References
Baker, S., and T. Herrman. 1995. Evaluating particle size. MF 2051. Department of Grain Science and Industry, Kansas State University, Manhattan.
Goodband, D.R., M.D. Tokach, and J. Nelsson. 1995. The effects of diet particle size on animal performance. MF 2050. Department of Grain Science and Industry, Kansas State University.
Herrman, T. 1995. Sampling feed components and finished feed. MF 2036. Department of Grain Science and Industry, Kansas State University, Manhattan.
Koch, K. 1996. Hammer mills and Roller Mills. Northern Crops Institute, North Dakota State University, Fargo.