Are Hay Preservatives Safe for Horses?

Should you avoid purchasing hay treated with propionic acid (a preservative) for horses? Not necessarily, our nutritionist says.
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Are hay preservatives safe for horses?
If hay is clean, smells good, has good color, and is palatable, there’s no reason to avoid it just because it’s been treated with propionic acid. | Photo: iStock

Q.I’m starting to find hay to purchase for the next year, and I have found a source of what looks like very nice hay. However, it’s been treated with propionic acid. What is this, and is it safe to feed to horses?

—Via e-mail

A.Now is a great time to be hay shopping for the coming year to avoid paying the premium rates that are more common during winter

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Written by:

Clair Thunes, PhD, is an equine nutritionist who owns Clarity Equine Nutrition, based in Gilbert, Arizona. She works as a consultant with owners/trainers and veterinarians across the United States and globally to take the guesswork out of feeding horses and provides services to select companies. As a nutritionist she works with all equids, from WEG competitors to Miniature donkeys and everything in between. Born in England, she earned her undergraduate degree at Edinburgh University, in Scotland, and her master’s and doctorate in nutrition at the University of California, Davis. Growing up, she competed in a wide array of disciplines and was an active member of the U.K. Pony Club. Today, she serves as the district commissioner for the Salt River Pony Club.

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