An old dairy ration evaluation tool has a new trick. The Penn State Particle Separator (PSPS) received an update for 2013 in the form of a 0.16-inch (or 4 mm) screen. This new, smaller screen adds the ability to estimate the quantity (%) of a forage or total mixed ration (TMR) that provides physically effective fiber (peNDF) to the cow.
Feed particles captured on this new sieve are often high fiber in nature. Initially, these particles will be likely trapped in the forage mat of the rumen, but they are broken down easily with minimal rumination or by rapid microbial action. Research has shown that particles of this size have a small yet significant impact on buffering the rumen.
Commonly called the "Penn State Shaker Box," this particle separator has been used on farms since its creation in 1996 to quantitatively determine particle size in forages and total mixed rations. This newest update allows for even more thorough evaluation of feeds on the farm. The desired percent of particles landing in each sieve are listed below.
