With corn silage harvest coming up, it is important to take your time and make sure you put up the best feed that you can. Dairy One offers Corn Silage Processing Score (CSPS) testing. CSPS is determined by drying ~160 grams of a corn silage sample and shaking the dried sample for 10 minutes on a series of sieves.
The percentage of starch that passes through the coarse sieves (particles < 4.75 mm) represent the adequately processed kernels. The percentage of starch passing through the 4.75 mm sieve is determined by subtracting the amount of starch that did not pass through the 4.75 mm sieve from the total starch in the sample. The percentage of starch that passed through the 4.75 mm sieve is the CSPS. The guidelines for interpreting the results are:
- Greater than 70% - Optimum
- 50 - 70% - Adequate
- Less than 50% - Inadequately Processed
The concept is similar to that of the Penn State Shaker Box in an attempt to quantify particle size distribution. Properly processed silage should achieve a balance between coarse particles to stimulate chewing and rumination and fine particles to enhance digestibility. The CSPS specifically targets starch. Starch in the coarse fraction will be less digested than that in the fine. Lower CSPS scores associated with starch in the coarse fraction can result in an increase of fecal starch. Studies from VitaPlus and Dr. Jim Ferguson at the University of Pennsylvania show that a decreasing fecal starch can result in increased milk production. In contrast, fine particles passing through a 1.18 mm sieve are more readily digestible, but rapid fermentation may cause problems when rations low in effective fiber are fed.
Use the CSPS to ensure that the kernels in your silage are properly processed to promote starch digestibility and enhance the feeding value of your silage.