Equine Scientist Does Not Recommend Feeding DDGS to Horses

Distiller's grains have become a staple in some bovine diets, but a Kansas State University researcher is not recommending that they be used in horse rations.

"People have asked 'can I feed dried or wet distiller's grains with soluble (DDGS) to my horses?'" said Teresa Slough, equine nutrition specialist with K-State Research and Extension.

Given the information researchers have so far, Slough said she would not recommend feeding DDGS to horses.

There has been little research done in feeding DDGS, a byproduct of the ethanol production process, to horses, she said. So far, the studies that have been done examined feeding DDGS for only a short period of time.

"There is no information available so far on the long-term effects of feeding DDGS to working horses, mares or foals," she said.

The upside of feeding DDGS to horses is that they will eat it and, in fact, they like it, said Slough, who is an assistant professor in K-State's Department of Animal Sciences and Industry. In addition, it is sometimes a less expensive source of protein.

But Slough warns that the disadvantages outweigh the advantages.

"Horses are very susceptible to fumonisin poisoning from moldy corn. Fermentation during ethanol production doesn't destroy the mold, rather it is concentrated.

"Feeding DDGS contaminated with fumonisin just once could cause death," she said.

Another disadvantage, the researcher said, is that DDGS has a high phosphorous content.

"Unless the other feedstuffs in the horse's diet are very high in calcium, the potential exists to create a diet inversed in its Ca:P ratio and negatively affect bone development," Slough added. "This is of particular concern with broodmares and foals."

DDGS has a high sulfur content, which also makes it problematic for horses.

"Sulfur toxicity in horses, although rare, can result in colic, jaundiced mucous membranes, labored breathing, cyanosis and convulsions, followed by death," she said.

"The bottom line is, feeding DDGS to horses is not recommended unless it's been tested for fumonisin and contains less than 5 parts per million, and then it should only comprise a small percentage of the total diet".