Georgia Stable Owner: Tests Reveal Monensin in ADM Feed

Georgia Stable Owner: Tests Reveal Monensin in ADM Feed


A Georgia stable owner says the ADM grain she was feeding tested positive for monensin. Roslyn Johnson of Grantville is waiting for quantitative test results to learn how much monensin is allegedly in the feed.

The Southgate Farm owner says she had a feeling she needed to test her grain produced by ADM Alliance Nutrition, Inc. after learning about feed allegedly tainted at Camelot Farms Equestrian Center in South Carolina. That farm’s feed is also manufactured by ADM

“I sure am glad I did,” says Johnson. She says she was feeding ADM Patriot Performance Horse Feed 12-10 produced at the mill in Cordele, Georgia. Specifically, lot GA35614 tested positive for monensin, according to lab results from Michigan State University Diagnostic Center for Population and Animal Health.

Inspectors from the U.S. Food and Drug Administration (FDA) have spent time at the Cordele manufacturing facility investigating. Since the initial complaint, the investigation was turned over to the FDA by the South Carolina Department of Agriculture.

We asked ADM to comment on why the company has not taken action, now that there are allegations of monensin tied to two different types of ADM equine feed out of the same mill. Company spokesperson Jackie Anderson responded, “we have reached out to the customers who have contacted us with concerns and are reviewing test results and any additional information they’ve provided. We have also taken feed samples from their dealer and have sent those to a third-party for additional testing.”

FDA spokesperson Megan Bensette tells Rate My Horse PRO, “there is no acceptable amount of monensin allowed in equine feed – it is not approved.” The Federal Food, Drug, and Cosmetic Act requires animal feed, like human food, to be truthfully labeled and contain no harmful substances.

Monensin is used to improve feed efficiency in cattle and can be found in premix formulas. Cross-contamination in the milling process during the formulation of equine feed, due to human error, is one way horses can become exposed.

Monensin is highly poisonous to horses and affects the heart and skeletal muscles. The level of toxicity is dose and individual dependent. Symptoms of monensin poisoning may include colic, sweating, muscle wasting, bloating, kidney failure, damage to the heart, respiratory distress, stiffness, and the inability to stand.

Young Rider Sophie David, who has campaigned Beau, was planning on moving him up to the Advanced level this year, but those plans are uncertain as is Beau's future health.

Distressed by the feed results, Johnson took her 16-year-old Intermediate level eventer to the University of Georgia College of Veterinary Medicine on Friday for a cardiac assessment. The stoic bay gelding, known as Beau, is the picture of fitness, according to an electrocardiogram while at rest and on the lunge. 

A blood sample measuring cardiac troponin was also done since it can detect even subtle pathology. “The vets all came out and wanted to talk to me,” Johnson says. Beau’s troponin level was .37 ng/mL. Research shows clinically healthy horses have troponin levels less than .03 ng/mL. An echocardiogram established a baseline. UGA’s initial diagnosis is myocarditis or inflammation of the heart.

The veterinarian’s discharge instructions for Beau state:

“Despite the normal physical examination and normal exercising telemetry, with the history of exposure to monensin, and the findings from the exam today, the best recommendation would be to repeat the serum troponin concentration on Monday or Tuesday, rest Beau for the next 3 weeks and to repeat the echocardiogram and exercising telemetry prior to increasing his level of work. The mainstay of treatment for myocarditis is rest and anti-inflammatories, as such flunixin meglumine (Banamine) was prescribed at a low dose for 5 days.”

By Monday, the same lab retested another blood sample from Beau revealing the gelding’s troponin level almost doubled to .61 ng/mL. The thoroughbred will be re-tested again after this weekend. A dozen other horses at the boarding stable also ate the allegedly contaminated feed. All but two have elevated troponin levels that range from .04 ng/mL to .97 ng/mL.

Young Rider Sophie David, who has campaigned Beau, was planning on moving him up to the Advanced level this year, but those plans are uncertain as is Beau’s future health.

Johnson says she filed an official complaint with the FDA yesterday regarding ADM’s allegedly tainted feed. “This has been overwhelming. I am trying to close the loop.”

Stay with Rate My Horse PRO as we continue to follow this developing situation.