Recall calls for closer scrutiny

Read the Fine Print! Health-conscious equestrians have learned to pay as much attention to what is in their horses' grain as in the food on their own tables. Like grocery store packaging, the label on a bag of horse grainRead the Fine Print! Health-conscious equestrians have learned to pay as much attention to what is in their horses' grain as in the food on their own tables. Like grocery store packaging, the label on a bag of horse grain

Story originally posted by Staff

Health-conscious equestrians have learned to pay as much attention to what is in their horses’ grain as in the food on their own tables. Like grocery store packaging, the label on a bag of horse grain lists the ingredients from the highest percentage to the lowest. What the labels do not say, however, may be the most important variable of all: the source of the ingredients.

The issue of "who" is in your horse’s grain-known as traceability-was at the crux of an alert in May involving certain Purina horse feeds. Contaminated grain resulted in what the company termed a "voluntary recall" or "product retrieval" after aflatoxin, a potentially life-threatening form of mycotoxin, was found in Purina horse feeds that had been distributed to dealers in 17 East Coast states.

Purina immediately notified those dealers, who removed the affected lot numbers from their stock. But traceability could go only so far. Many customers had transferred feeds they had purchased into their own containers and had discarded the bags on which the lot numbers were printed. All they could do was watch their horses, wait and hope. (To date, Purina says there have been no confirmed cases of aflatoxin-related horse illness from its recalled feeds.)

Traceability in that case was further complicated because neither consumers nor feed manufacturers knew the answer to the key question: Where had the tainted ingredient come from? A Purina spokeswoman said the company traced the contamination to "a single ingredient from a single supplier." Although it ceased using that supplier, Purina did not disclose its identity or the ingredient at issue. The possibility remained, therefore, that manufacturers of other brands of horse feeds could have purchased the same ingredient from the same supplier.

That prompted nationwide efforts in the feed industry to determine the nature and source of the affected ingredient. Some feed manufacturers and dealers said they had heard the culprit was peanut hulls (feed ingredient byproducts sometimes contained in less expensive brands of horse feed). Those reports, however, were unconfirmed, and the company that supplied the contaminated ingredient to Purina has remained anonymous.

The incident raised awareness among horse owners about the importance of knowing "who" is in the feed they give their horses. While several types of mycotoxins can harm horses, aflatoxins are known to be particularly dangerous. Affected horses may show signs such as feed refusal, fever, weight loss, sluggishness and bloody diarrhea. Worse, the toxicity can be cumulative. At levels greater than 50 ppb (parts per billion), aflatoxins can cause liver and kidney damage, jaundice, birth defects, tumors and can suppress the immune function. Even at non-critical levels, they can detract from a horse’s performance, condition and appearance. Some have suggested mycotoxins may also contribute to colic.

These threats can be reduced by buying grain from manufacturers of premium horse feeds, which utilize ingredients that inhibit the effects of mycotoxins. (See sidebar, "Mycotoxins: preventive feeding.") Traceability is also easier to determine with such manufacturers, many of whom add to their feed name-brand products available only from proprietary sources.

Not all feed companies, however, are as careful about where ingredients are purchased from and subsequent quality testing of ingredients and additives coming into their facility, said Dr. Amy Gill, an equine nutrition consultant in Lexington, Ky.

"Consumers need to be aware of this fact and ask questions if they are unsure of the quality control measures in place for their brand of feed. If the answers don’t suffice, find another brand. Purchasing feed from a reputable manufacturer lessens the chance of contamination," she said.

Traceability and ingredient sourcing are "the sole responsibility of the feed manufacturer" and are based upon the quality control measures a company has in place to prevent contamination of feed made in its facility, she added, noting that manufacturers are not required by law to divulge the source of any ingredients.

While cases of horse feed contamination have been rare, even general nutrition concerns underscore the importance of traceability in horse feeds. Does it really matter which company manufactured the selenium, for example, contained in some complete and supplemented feeds? As with numerous other grain ingredients, all selenium is not created equal. A feed whose label lists selenium as an ingredient may contain the organic or inorganic form. Organic selenium is far more bio-available-and therefore provides more effective nutrition-to horses than inorganic types.

If the label doesn’t specify the source of its selenium or any other component, consumers can inquire whether the feed contains the specific name-brand product they desire. Should the answer be no, one can change to a higher-end feed manufacturer whose formula includes the name brand. Another option may be to research whether the product can be purchased separately and top-dressed, as can some organic digestive aids available in feed stores or online.


Taking such extra steps is worth the effort to "hands-on" horse trainers like Richard Ketch, owner of Equine Transitions in Lexington, Ky., who has long mixed his own feeds for his string of Thoroughbred racehorses. His feeding program is based on whole (unprocessed) grains, such as rolled oats and barley, and individual organic supplements he uses to "tweak" the recipe for individual horses.

"I am the front-line defense for my own health, and I am the same for my horses," said Ketch. "Sure, it’s easier to buy a bag of sweet or complete feed, but how do you know from week to week what’s in there?"

His is a point well taken. Aside from premium horse feeds, whose formulas remain constant, many manufacturers use what are called "least-cost" formulas to mix their grains. Even some nationally recognized brands of horse feed use those formulas to keep their products attractively priced. That means they use whichever substitutable feed ingredient byproduct is least expensive at the time. One week their grain mixes may contain peanut hulls, the next week corn screenings, perhaps the following month a soy byproduct. Such variations greatly complicate traceability, making it difficult-if not impossible-to ascertain "who" is in your horse’s feed.


Given the difficulty of traceability in grain, what can be done to protect horses from mycotoxins?

"One precaution is to routinely add a mycotoxin binder to all manufactured feeds," said Dr. Amy Gill, an equine nutrition consultant in Lexington, Ky. While that has not yet become the norm, makers of premium horse feeds recently began including mycotoxin-fighting products in their formulas.

Gill noted such additives are designed to "prevent mycotoxins from exerting their effect in the digestive tract by binding to them and rendering them inert. When fed on a daily basis with the normal [grain] ration, the risk of mycotoxin poisoning is greatly reduced."

Researchers in Canada examined the effects of these additives-referred to as yeast cell wall polymers or mycotoxin "adsorbents" (the opposite of absorbents)-in 2002 and 2003. Clinical were trials conducted at the University of Guelph’s Equine Centre in conjunction with its Department of Animal and Poultry Science.

The Canadian feeding trials were done on nine sedentary mature mares divided into three groups, one of which was a control. The second group received fusarium mycotoxins in the daily grain ration (a blend of wheat and corn). The third group was fed contaminated grain supplemented with a mycotoxin adsorbent.

In comparing the groups, researchers found the mycotoxin effects were lesser in the horses given the mycotoxin adsorbent. They reported the supplement alleviated a typical mycotoxin effect: reduced feed intake. In addition, fewer metabolic changes generally associated with mycotoxin poisoning were observed in the group that received the mycotoxin adsorbent. While feeding contaminated grain increased enzymes associated with liver damage, researchers found that adding the mycotoxin adsorbent lessened the severity of their effects.

The results of the study, written by Trevor Smith, H.V.L.N. Swamy, Susan Raymond, were published by the American Society of Animal Sciences (J. Anim. Sci. 2003. 81:2123-2130).

The research was supported in part by the Ontario Horse Racing Industry Assn.; the Ontario Ministry of Agriculture and Food; the Rural Job Strategy Fund; and Alltech, a global animal nutrition company based in Nicholasville, Ky.

For further information, contact Manoella Alves at Alltech: