There’s a tremendous amount of money invested in silage, from growing the crop to storing it. Yet shrink on dairies ranges from 15 to 25 percent, if not more! This level of shrink can equate to a loss of 15 to 25 cents for every dollar invested in putting the silage up.
Where silage shrink occurs
The largest amount of shrink and reduction in quality seems to occur at the top of the silage pile. This part of the pile is the worst in terms of packing density. It’s also exposed to the most oxygen. This enables oxygen to easily penetrate the silage, creating an environment for molds and yeast to replicate, which will lead to deteriorated silage (aka, top spoilage).
Generally, top spoilage represents about one-third of what was once good silage. For example, 4 inches of top spoilage was originally 12 inches or 1 foot of quality silage. It is best not to feed the spoiled portion of the silage in order to minimize the risk of costly health and production challenges. This part of the pile, therefore, should be a major focus in terms of management.
Making silage is easier said than done and is much like piecing a puzzle together. Since there are so many pieces to the silage puzzle, it can be difficult. The key factors include making sure forages are harvested at the correct maturity and moisture, proper packing, excluding oxygen and managing the face at feed out. In terms of top spoilage, all these areas can be a factor, with packing density and excluding oxygen being most important.
Cost-effective ways to improve silage management:
- Silage packing density should be 15 lbs. DM/ft³ or more.
- Typically, a ratio of one pack tractor to one harvester will achieve 15 lbs. DM/ft³.
- Design piles to allow for more packing on the side or shoulder of the pile.
- Use a temporary cover overnight or in between any breaks in harvest.
- Utilize a mold inhibitor on the silage surface prior to covering.
- Cover the pile as quickly as possible once harvest is complete.
- Seal plastic edges and seams with gravel bags or dirt to prevent airflow under the plastic.
- Only unseal what you need for the day to limit the oxygen exposure of the silage.
Higher quality silage with lower shrink will benefit your bottom line. Given that silage is a major component of the cow’s diet and impacts the types and amounts of other ingredients in the diet, taking steps to improve silage management practices and specifically focusing on reducing top spoilage can have a big impact on reducing silage shrink and improving quality. There is a lot of money invested in putting up silage, so it is crucial to make sure that it is put up correctly to minimize shrink, retain nutrients and ultimately preserve that investment.