‘Vomitoxin’ a nasty word for this year’s wheat crop

WOOSTER, Ohio — A word perhaps as disgusting as it sounds has reeked havoc on wheat growers across the cornbelt states.

V-o-m-i-t-o-x-i-n — a mycotoxin that causes suppressed appetite in livestock, also has the potential for harmful effects on humans.

Scabby grain, a disease which attacks the wheat during flowering and potentially produces vomitoxin, can cause symptoms of food poisoning. Long-term consumption can cause a dangerous reduction in appetite, weight loss, damage to the gastro-intestinal tract and impair the immune system, according to information provided by Ohio State University’s Crop Observation Recommendation Network.

Testing samples

Although costly, feed mills across the region are conducting tests to determine how much vomitoxin is in the grain, which determines whether it will be accepted, and for what use.

At the Land O’ Lakes branch in Wooster, Plant Manager Brad Starlin has seen his fill of the stuff. He estimates 40-50 percent of the wheat delivered has exceeded 2 parts per million of vomitoxin.

Each load is chemically tested, he said, an expensive and time-consuming process, but one that assures a safe product. He can accept up to 6 parts per million, but wheat that is destined for the flour mill industry must be under 2 parts per million.

Head scab and vomitoxin thrive under wet conditions — like those seen this spring and last fall, when high amounts of vomitoxin were reported in the corn crop.

“It started last fall and it just went right into wheat harvest,” Starlin said.

Fungicide helped

Tom Pugh, an agronomy salesman for Agland Co-op, said the difference in good and poor wheat this year had a lot to do with whether the farmer applied fungicide. Those who did typically had higher test weights per bushel, and better quality grain.

“The fellows that put some fungicide on had a lot better quality wheat,” he said. “With the fungicide were seeing about 60 pounds test weight (ideal).”

Starlin said his mill is seeing similar results, adding that only a few farmers were able to apply fungicide, because of the price, and also because of the wet conditions, which reduced the time frame to apply it to only a few days.

Ralph Wince, a grain merchandiser for Agland, said he expects about 75 percent of the company’s Canfield-Lisbon market to make flour quality wheat, while the New Philadelphia location is experiencing the opposite, with the majority only good for livestock feed.

Very prevalent

Crop experts with Ohio State University Extension report that Ohio is experiencing upwards of 60 percent incidence of head scab. They advise farmers to test their grain before it is used for consumption.

“Farmers shouldn’t think that it’s OK to handle or feed scabby grain without actually testing and knowing how much toxin is in it,” said Pierce Paul, a small grains specialist with OSU Extension, in a released statement.

“Much of Ohio’s wheat crop is testing positive for vomitoxin, with results ranging from 1 part per million to as high as 10 parts per million,” said Stan Smith, an OSU Extension program assistant. “In some cases the grain elevator is accepting the wheat after discounting the price anywhere from a nickel per bushel up to more than a dollar per bushel. In some cases the wheat has been rejected at any price by the elevator.”

Tolerance levels

Livestock can tolerate higher levels of vomitoxin than humans, depending on the feed ratio and the species.

Wheat containing up to 10 parts per million of vomitoxin can be fed to adult beef cattle with the stipulation that the total ration should not exceed 10 parts per million for beef cattle and should not exceed 5 parts per million for adult dairy cattle, according to the U.S. Food and Drug Administration.

For calves and other animals except swine, wheat containing vomitoxin up to 5 parts per million can be fed, if it composes no more than 40 percent of the diet.

Wheat containing 5 parts per million vomitoxin can be fed to swine if it composes no more than 20 percent of the diet. The new FDA Guidance for Industry document can be found in its entirety at www.fda.gov/Food/GuidanceComplianceRegulatoryInformation/GuidanceDocuments/NaturalToxins/ucm120184.htm.

Straw quality?

While the grain may be the primary focus, the No. 1 byproduct of wheat — wheat straw — also is affected.

Paul said straw from scabby fields contains vomitoxin and other mycotoxins, with test results showing straw can exceed 2 parts per million, even in fungicide-treated fields.

He said the same caution should be used with moldy straw, as would be used with grains, and encourages having straw tested before using it for bedding or silage.

The risk of contamination is much lower when used for bedding, he said. However, straw with high levels of vomitoxin should still be avoided, because it’s impossible to know how much the animals may consume.