Southeast Iowa cattle herd thriving on sawdust-based feed
Cows eat mixture like candy, farmer says -- but is it nutritious?
While it’s not quite spinning straw into gold, Bob Batey is converting sawdust from his lumber mill into nutritious and palatable feed for his cattle.
When Batey fills his feed bunks with the 70 percent sawdust ration, his cows eat it like candy, plunging their faces into it and licking their lips.
“They like it. It’s good for them. It’s economical. And it’s green.” said Batey, 85, an outside-the-box thinker whose entrepreneurial endeavors have often turned dross into profit, especially in the custom machinery he has “invented” for use in his family’s large and successful lumber mill.
“They are a happy bunch of cattle,” said Tara Wellman-Gerdes, a West Point veterinarian who is monitoring the health of Batey’s 50-cow herd of Angus and Charolais near Mount Pleasant.
The cows, who are expecting calves in March, are the picture of health, she said.
Animals can barely digest untreated sawdust, which consists of more than 50 percent cellulose and about 30 percent lignin.
Stephanie Hansen, an assistant professor in the animal science department at Iowa State University, said lignin wraps itself around cellulose, giving wood its strength and rigidity and acting as a barrier to the digestibility of cellulose.
“You could potentially free up the cellulose, which has high food value,” she said.
Breaking the cellulose-lignin bond is precisely how Batey extracts feed value from sawdust, he said.
As long as the cows are maintaining good health, Hansen said the process sounds like “a good example of how producers are getting creative in feeding their livestock” at a time when traditional feedstocks are expensive and in short supply.
Dan Loy, an ISU animal science professor who participated in tests of sawdust as sheep feed 30 years ago at Penn State University, said he is skeptical.
“Based on my experience at Penn State, which found sawdust to have very low feed value, I doubt sawdust would contribute more than the bare minimum of nutrients,” Loy said.
Byron Leu, an ISU extension regional beef specialist at Fairfield, said he too was skeptical until he sat down with Batey and discussed the project.
“When I got the phone call, I thought someone was pulling my leg,” he said.
After the meeting, however, Leu said he is convinced that Batey “is trying to figure out ways to help people who don’t have adequate forage find an inexpensive source of fiber and carbohydrates.”
Leu said he and his colleagues are conducting similar experiments to break down the lignin and improve the digestibility of cornstalks.
“Not much grows out of the ground that cows won’t eat,” said Batey, who has been raising beef cows and calves since 1959.
He first tumbled to the idea of feeding them sawdust after observing cows eating sawdust that had washed into their pasture from an Illinois paper mill.
Batey said he deduced that something happened in the mill to turn an otherwise indigestible substance into palatable food.
In the late 1970s, when hay and pasture were scarce, Batey said he began experiments to duplicate that process.
“I soaked the sawdust in nitric acid to break down the bond between the cellulose and lignin and cooked the mash in a big stainless steel vessel,” he said.
Though the cows readily consumed the 75 percent sawdust ration and did well on it, Batey said he discontinued the practice when hay and grass became more abundant.
With hay and grass again short during the drought of 2012, Batey resolved to resume the practice but discovered that nitric acid, a precursor in the manufacture of explosives, had fallen under strict government regulation.
He then collaborated with Mike Kassmeyer of Quality Plus Feeds in St. Paul, Iowa, to develop the ration his cows now relish to the tune of 30 pounds each per day.
“It’s a green way to raise cattle. You are basically recycling something that would otherwise go to waste,” said Kassmeyer, whose firm mixes Batey’s sawdust with corn, vitamins and minerals, as well as other ingredients that he declined to specify, presumably for proprietary reasons.
Kassmeyer and Batey said the sawdust ration has food value equivalent to grass hay.
The green aspect is definitely one of the benefits, said Wellman-Gerdes, a cattle specialist.
Feeding sawdust eliminates all the fuel consumption, chemical inputs and intensive land use that would be required to feed grain or hay, she said.
In an era of high grain prices and diminishing hay and pasture acreage, it “is definitely a positive” to take advantage of otherwise wasted byproducts, she said.With corn at $7 a bushel, beans at $13.50 and hay at $200 a ton, a low-cost, nutritious and palatable sawdust-based ration “could get the attention of cow-calf beef producers pretty fast.” Leu said.