Combating vomitoxin in
grain supplies
After high infection rates in 2009, producers must be prepared
for possible DON contamination.
Vomitoxin, more commonly known as DON, originates from the
mold Fusaruim gramineanum. It infects cereal grains (wheat
barley and oats) in addition to corn and sorghum. Growth on
the grain kernel is dependent upon high moisture and warm
conditions at the time of flowering for wheat or late in the
growing season for corn and sorghum.
During the 2009 season, there were several areas in Europe
and the U.S. that experienced climatic conditions precipitating
a high level of infection. Water-logged soils prevented early
harvesting thus allowing more time for the mold to grow.
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greatest concern from the 2009 crop. Infected corn has a
salmon or pink color of the ear at the tip, although shelled corn
may look normal. Most elevators apply a rapid test for DON
but a more comprehensive laboratory procedure (HPLC) is
used to determine the presence of other molds and is highly
recommended although expensive.
Infected wheat develops a scab and the kernel is thin and
light in weight. Screening grain removes much of the toxin as
it is concentrated in the fines and bran component of wheat.
See a critical analysis of the 2009 feed
contamination.
www.WATTAgNet.com/15424.html
Mold toxin is water soluble and thus concentrates
in processed grain by-products and is present at a
level three times higher in wheat bran or in the DDGS
products available for livestock feeds compared to
the original grain.
Although all livestock are sensitive to DON, pigs
are the most sensitive species and gestating sows
and piglets should be fed the best -quality grains.
Typically anorexia or feed refusal is observed when
DON is present. When pigs consume contaminated feed at a high level of intake emesis (vomiting)
occurs hence the name “vomitoxin” attributed to
this mycotoxin.
DON is not a mold produced during storage if
corn is properly dried to less than 14% moisture
and the bins are aerated and the corn is held at
under 45 F. There are several products on the market with
value to increase feed intake and weight in pigs. Research is
continuing on several products to determine the most effective
additive for swine diets. [FM]
Adapted from a presentation made at the 2010 Alltech
Symposium
Fusarium colony (pink mycelium) growing from wheat kernels, courtesy of BioVision
Seed Labs.
Other molds that are closely associated with DON are T- 2
toxin (hemorrhagic changes) and zearalenone (reproductive
dysfunction in sows).
Corn grain from the 2009-2010 harvest in the region from
Iowa to the east coast was infected by DON. Although the
other fusariummolds are often present in grains, DON is the
