One of the most heavily attended breakout sessions at the 2014 Professional Dairy Producers of Wisconsin Business Conference, March 13-14, was a session on “shredlage.” During that session, Dr. Randy Shaver, University of Wisconsin-Madison dairy scientist, discussed a major feeding study underway at UW-Madison’s Arlington research farm.
The 16-week trial involves 120 cows, each fitted with an SCR collar to monitor rumination numbers. The ration for one group of the cows in the study provides 50 lbs. of the brown midrib (BMR) corn shredlage per day; the ration for the second group has 50 lbs. of the conventionally processed BMR corn silage; and a third group is being fed 40 lbs. of BMR conventionally processed silage along with 10 lbs. of chopped dry alfalfa hay and an extra 2.6 lbs. of dry ground shelled corn. Shaver reported that the cows in the trial are averaging up to 110 lbs. of milk per day.
In a previous UW-Madison study involving 112 cows, starch and fiber digestibility and dry matter intake improved in a ration utilizing shredlage. Fat-corrected milk was up 2 lbs. per cow per day.
A summary of that study concluded the proportion of material on the top (coarsest) screen of the Penn State Separator was greater for shredlage. This was also the case for the TMR which contained shredlage. There was no sorting of the TMR for either treatment. DMI tended to be greater for cows fed shredlage, as did fat-corrected (FCM) and energy-corrected milk. The FCM response to shredlage increased as the treatment period progressed. Kernel processing score and ruminal and total tract starch digestibilities were greater for the shredlage diet.
Corn shredlage differs in how the stalks are torn and shorn in a lengthwise manner rather than being cross-cut with conventional choppers. With a proper setting of the gap between the rolls, which run at a different speed, the corn kernels will also be processed or crushed in order to make the starch readily available.
Shredlage equipment increases the theoretical length of cut of the corn silage to between 26 and 30 millimeters (26 millimeters is 1.1 inches) with a 2- to 3-millimeter gap between the rolls, Shaver said. He noted that conventional corn choppers have a theoretical length of cut of 13 to 19 millimeters and a roll gap of 1 to 3 millimeters.
Shredlage equipment continues to evolve. Past limitations have included heavier wear and tear on equipment, as well as slower field travel slows and higher horsepower requirements.