Effectively using mold inhibitors and mycotoxin binders

Posted on September 8, 2015 in Swine Performance
By Dr. Leah Gesing

Some parts of the Midwest experienced extended periods of both rainfall and drought this summer.  It is expected that affected areas will have a higher prevalence of molds and mycotoxins in harvested grains this fall.  In fact, Dairyland Laboratories, Inc. recently tweeted that, since June 1, more than 60 percent of small grain (wheat, barley, oats, etc.) samples submitted for mycotoxin testing have contained greater than 5 ppm vomitoxin.  That is well above the 0.5 ppm threshold for complete feeds that is known to produce negative impacts on the pig.

Molds are the precursors to mycotoxins and high enough levels of mycotoxins can negatively impact growth and reproductive performance in pigs.  Therefore, it’s important to understand how and when certain types of molds grow asj well as what types of feed additives are available to control mold growth and mitigate the effects of mycotoxins when consumed by pigs.

Types of molds
There are two general types of molds (fungi) – field and storage fungi.  Field fungi grow on crops prior to harvest.  Common types include the Fusarium species, which produce vomitoxin, zearalenone, fumonisin, DON and T2.  Field fungi occur due to certain weather conditions.  As a result, whole geographic areas are expected to be affected.

Storage fungi have a more localized distribution within bins due to storage conditions and they can grow at very low moisture levels.  Storage fungi can be more difficult to detect because not all grain in a bin may be affected.  Thus, extensive sampling is required.  Common types include Aspergillus and Penicillium, which produce mycotoxins such as aflatoxin.

Feed additives
Two basic types of feed additives can help mitigate the growth of molds and the effects of mycotoxins.  These products are commonly referred to as mold inhibitors and mycotoxin binders.  It’s very important to understand that these two types of feed additives do not perform the same function.

Mold inhibitors can be added to grain or complete feed to prevent mold growth.  Thus, they reduce the risk of mold growth and mycotoxin production in grain or feed.  Mold inhibitors have no effect on mycotoxins that are already present.  That means that, even if additional mold growth is prevented by the inclusion of a mold inhibitor, mycotoxins may still be present in grain or feed.  Water is required for mold growth.  As such, typically more mold inhibitor will be required the higher the moisture content of the grain.

In contrast to mold inhibitors, products referred to as mycotoxin binders aid in the binding, deactivation, and/or breakdown of mycotoxins inside the gut of the pig.  They are commonly added to complete feed.  This type of product will do nothing to inhibit mold or mycotoxin proliferation in grain or feed.

Limiting effects of mycotoxins
It’s important to consider all grains and grain byproducts that may be contaminated with mycotoxins.  If corn that is used in fermentation has been contaminated with mycotoxins, the resulting distiller’s grains may contain as much as three times the concentration of mycotoxins as the source corn (Wu and Munkvold, 2008).

Don’t let grain contaminated with mycotoxins impair the growth or reproductive performance of your pigs.  The Vita Plus swine nutrition team can help you determine whether molds and mycotoxins could be a problem in your grain and complete feed.  We can also help you decide if the use of a mold inhibitor or mycotoxin binder may be prudent in your operation.

About the author:  Dr. Leah Gesing is a Vita Plus swine technical sales and support specialist.  She earned her bachelor’s degree in animal science from Iowa State University.  She continued there to earn her master’s degree in animal physiology, studying on-farm factors affecting market hog transport losses.  She then went on to the University of Illinois to earn her Ph.D. in animal sciences.  While in school, Gesing was involved with numerous research projects, teaching experiences, internships, and international travel.  Specifically, she conducted applied research in swine genetics, health, management and reproduction with Dr. Mike Ellis.  Her Ph.D. project evaluated the effect of timing of OvuGel® administration on reproductive performance in gilts synchronized for estrus.

Category: Feed quality and nutrition
Swine Performance