"Feeding wheat to dairy cattle is very uncommon because it is too expensive," said Mike Hutjens, University of Illinois dairy specialist and professor emeritus.
"The thumb rule is we can pay about 10 percent more for wheat than corn on a pound-for-pound basis," he
"That usually means wheat is too expensive compared to corn prices."
However, this year wheat quality is reduced due to scab, which can lead to the development of mycotoxins including vomitoxin.
"If your wheat is discounted 50 to 80 percent, then wheat becomes a possibility compared to corn," Hutjens
advises dairymen to gradually increase the amount of wheat in a ration by replacing corn.
"I would do 10 percent replacement for a batch of feed and then 20 percent replacement," he
"Then monitor the dry matter intake, the fecal consistency, milk production and look for signs of acidosis."
The level of vomitoxin in a ration should not exceed five to six parts per million in the total ration dry matter, Hutjens
Vomitoxin also can be found in the wheat straw.
"This is important because a number of farmers in the Midwest feed a low-energy, high-straw diet," Hutjens
does not recommend feeding any mycotoxin-contaminated grain to dry cows or springing heifers.
"You don't want to create a hormonal shift on those animals," he
It is important for dairymen to get a uniform sample of the wheat.
"It can be very difficult to get a uniform sample," Hutjens
"So you might need to get the wheat tested a couple of times."
If the wheat is below 14 percent moisture at harvest, he
said, storage will not impact the levels of vomitoxin.
"I wouldn't expect it to change much in storage as dry straw or dry grain," he
However, if the wheat is wetter than normal, the vomitoxin levels could increase in storage.
About three years ago, when wheat was the same price as corn, there was an opportunity to feed wheat to cattle.
"We don't go above 25 percent wheat in a ration because it is a very fast starch compared to corn, which is a slow starch," Hutjens
How the wheat is processed also is important when balancing the ration.
"I would either feed cracked or rolled wheat, I don't think we need to hammer it and make flour out of it," Hutjens
"But much like barley, wheat should be cracked because if you feed whole wheat or barley to a cow, at least one-third will come through the manure."
All cereal grains should be processed before feeding them to dairy cows, he
"If the grains are not processed, the rumen bacteria can not attack the starch and the small intestine can not break it down," he