Ensiling unique forage byproducts – Dr. Michelle Der Bedrosian, Vita Plus

By Dr. Michelle Der Bedrosian, Vita Plus forage products and dairy technical specialist
Ensiling byproducts has been practiced for thousands of years.  It is more common in foreign countries and southern states where it makes sense to buy in bulk and store the byproduct for longer periods of time.  However, as producers attempt to save money where they can, buying and storing byproducts in bulk may become more common in the Midwest.

Some producers may chose to ensile byproducts because:

• Unique forages can provide a source of feed for the animals at a lower cost.
• Ensiling limits the growth of undesirable microorganisms and toxic substances during storage.
• Ensiling minimizes typical feed quality losses associated with storage.
• Ensiling limits shrink in stored byproducts for longer periods of time
• Ensiling can preserve and improve palatability of the feed.

Some popular unique forage byproducts to ensile are bypass sweet corn, bottomlage (what is left in the field after toplage is harvested), wet distiller’s grains, wet brewer’s grains, wet gluten feed, wet beet pulp and cannary waste products.  The keys to ensiling these materials are similar to making silage from any other crop:

1. Start with a high-quality product with sufficient sugars in it for fermentation.  Protein-rich feeds low in fermentable carbohydrates are going to be more difficult to ensile.  One strategy is to thoroughly mix these byproducts with easily fermentable, energy-rich byproducts, such as molasses.  In some situations, the molasses can be watered down to encourage an even distribution and to add moisture to the crop, should it require additional moisture.
2. Moisture content is key.  To ensile any unique forage byproduct, the moisture content should be between 25 and 50 percent moisture.  Wetter feeds will need more sugars to combat Clostridia.  While water can be added to drier feeds to obtain such moisture, this can be laborious, time-consuming, and can result in a product with wet and dry patches.  My personal recommendation is to try your best to get within this range.
3. Ensure the proper chop length.  The finer the chop length, the better silage the byproduct will make.
4. Pack the byproduct well.  This goes with the previous point about chop length.  Longer chop lengths are going to be harder to pack.  The key to making quality silage is to create a hospitable environment for acid-producing bacteria to grow.  This is an environment devoid of oxygen.  A good packing density will ensure a robust fermentation and minimize shrink.
5. Cover the byproduct with a quality, oxygen-limiting plastic.  This also functions to jump-start fermentation.  Studies have shown that crops covered with a quality, oxygen barrier plastic, such as Silostop^®, undergo a more rapid fermentation, have a lower pH, retain better quality and have less shrink.

Once the “silo” is sealed, acids will be produced and the byproducts will ferment.  Using an inoculant can help minimize shrink and maximize quality of the byproduct silage, but it is crucial to ensure the unique forage byproduct is not exceedingly hot at the time of ensiling.  Ideally, the temperature should not exceed 90 to 95 degrees F.  If the temperature exceeds 130 degrees F, it could kill any inoculant applied to the byproduct.

As with all silages, once the silo is opened and the byproduct is exposed to air, spoilage yeasts kept dormant by the oxygen-free environment begin to grow.  Byproducts with higher quantities of yeast, like wet distiller’s grains, will spoil faster and, in this case, an L. buchneri-based inoculant, such as Vita Plus Crop-N-Rich^® Buchneri inoculant, is ideal.

In conclusion, ensiling byproducts is not ideal in every situation.  Dry, excessively wet, or pre-fermented byproducts that will only be stored for a few days and fed immediately are not ideal to ensile.  However, ensiling offers a method to retain quality and minimize shrink, if done properly.