Reduce spoilage at the feedbunk

By Dr. Michelle Chang-Der Bedrosian, Vita Plus forage products and dairy technical service
Spoilage occurs in silages that have been exposed to oxygen.  Yeasts come out of dormancy and consume lactic acid, raising silage pH and creating a hospitable environment for aerobic bacteria and molds to grow and degrade silage quality.

Producers are often only aware of a spoilage problem because they see mold spots in their silages.  However, molds take quite some time to grow to be visible.  That means the spoilage problem has been occurring for a while by the time the molds are visible.  More often than not, silages that are spoiling do not have visible molds.  Other signs of spoilage include high yeast and/or mold counts and heating above ambient temperatures.

Using the threshold of 500,000 colony-forming units (cfu) per gram to define “spoilage,” laboratory analysis of yeast counts finds the majority of silages in the Midwest are undergoing active spoilage during the spring, summer and fall months.  However, when asked, most producers say they do not have a spoilage problem.  This hidden spoilage problem can be a major source of forage shrink and can also lead to decreased milk production, intakes, animal health, and farm profitability.

Prevent spoilage when possible
Many farmers have compared the cost of treating silages with the Crop-N-Rich^® Buchneri forage inoculant versus treating silages with a product containing propionic acid.  The benefit of using this inoculant is that L. buchneri produces acetic acid, a potent antifungal, which is more powerful than propionic acid at killing yeasts and molds that cause spoilage.  However, inoculation with L. buchneri can only occur at harvest, and not everyone foresees spoilage at that time.

Another option to reduce spoilage effects
Organic acids offer a great alternative to inoculation with L. buchneri.  They can be added to the TMR while it is being mixed and some can provide protection against spoilage, which helps the TMR stay cooler for longer.  Using the right acid, in the right amount, can provide a strategic advantage against spoilage.

Lactic acid, formic acid, propionic acid and acetic acid are just some of the organic acids that can be purchased to spray on feed.

• Lactic acid and formic acid are applied to feed to decrease pH quickly; they do nothing to protect the feed against spoilage.
• Propionic acid and acetic acid prevent spoilage.  Acetic acid (the same acetic acid that is produced by L. buchneri) is generally more expensive than propionic acid, but it is more effective at killing yeasts and molds.

With these benefits in mind, we recently reformulated Vita Plus Bunklife-L, a liquid product used to extend the freshness and useful life of TMRs and grain or commodity feed mixes.  It now contains a higher quantity of acetic acid to make this product even more effective at killing yeasts and preventing spoilage.

The best way to prevent spoilage is to be aware of a spoilage problem.  If you are unsure whether spoilage is occurring on your farm, sending a sample to a laboratory (on ice) will tell you the answer easily.  Your Vita Plus consultant can help you identify and solve a spoilage problem.