Caution recommended when feeding spuds to livestock

Jan 25, 2013

With corn prices soaring and potato prices declining, more farmers and ranchers are feeding spuds to their livestock, but those attending a workshop at the 45th Annual Idaho Potato Conference were cautioned that cattle can choke or bloat if their potato consumption is not closely monitored and regulated.

Drs. Benton Glaze and Rick Norell, University of Idaho (UI) livestock specialists, and Dr. Joe Guenthner, a UI agricultural economist, outlined challenges associated with substituting potatoes for regular cattle feed and fielded questions from growers eager to find an other use for their surplus spuds. Five hundred pounds of potatoes equal one ton of corn silage, they pointed out.

Glaze urged that if potatoes are fed to cattle, regular delivery schedules need to be established. If potatoes are held as feed for livestock, they need to be stacked on concrete, asphalt or a solid platform and covered. If stored on the bed of a loaded truck, they also need to be covered, he said.

“Potatoes can be successfully used as a feed source for various classes of cattle,” Glaze said.

Farmers and ranchers must be careful to protect their investments, he emphasized, noting a typical cow’s value can range from $1,200 to $1,400, but when fattened for slaughter, they can be worth up to $2,200.

“Avoid turning hungry cattle onto potatoes,” Glaze said, warning they risk choking to death on the spuds. The potatoes should be provided sufficient bunk space to prevent the cows— which should be kept calm—from competing for the spuds, which should not be frozen. The cows’ heads also need to be kept lowered when they are feeding so they do not choke.

The potatoes should not be fed whole but rather crushed or chopped for easier consumption. They also need to be free of rocks, soil and sprouts, Glaze said, adding that green potatoes must be removed because of the potential for glycoalkaloids poisoning, which can lead to staggering, weakness, decreased performance, loss of calves and even death.

Glaze suggested potatoes gradually be put into cattle diets because they ferment rapidly in a cow’s rumen and can cause fatal bloating or acidosis. Potatoes can cause increased urine output and more fluid fecal volume, requiring increased bedding needs, he mentioned.

Glaze, Norrell and Guenthner were asked if horses could be fed potatoes and whether spud disease and nematodes could be spread onto fields from the manure of cattle fed potatoes.

They said they do not believe disease would survive in a cow’s digestive tract, but Paul Patterson, another UI ag economist, said some cyst nematodes possibly could be passed through rumens. Seeds also could be found in manure.

It was noted that many Idaho feedlots feed potato slurry to cows, which eat 10 to 12 meals a day. Spreading potatoes on fields over winter raises molding and toxicity issues, they said.

Several years ago, the stench of rotting potatoes put into a pit on Devin Fielding’s family property in Shelley prompted neighbors to complain to county commissioners, who presented a stack of letters to the family. “Neighbors will lynch you if you put them in a pit,” Fielding remarked.

Norrell said livestock thrive on consistency. Cleaned and screened potatoes are the best to feed cattle. Idaho dairy cows eat 25 to 30 pounds a day. “They do like potatoes,” Norrell said. “Research and on-farm experiences clearly show whole potatoes can be successfully fed to cattle.”

Guenthner said feeding potatoes to livestock around the world historically has been viewed as a sign of difficult times. About 80 percent of a potato is water, making it a transportation challenge. A rule of thumb is that for each $1 change in the price of a bushel of corn, there’s a change of 40 cents in a hundredweight of potatoes, Guenthner said. — Mark Mendiola, WLJ Correspondent