The mere mention of the word alfalfa at a gathering of horse people can precipitate a wide spectrum of opinion, myth and conjecture. While many horse professionals favor alfalfa as a forage crop, many others fear it will produce all kinds of equine maladies. Truth be known, high-quality alfalfa hay offers many nutritional advantages, but like any feed, it must be properly managed within the context of the horse’s complete ration.
One clear advantage of alfalfa is its availability. In any given year, 60 to 70 percent of hay production in the U.S. is comprised of alfalfa or an alfalfa-grass mixture. Clearly, by excluding alfalfa as a forage option, the buying choices are vastly limited.
Alfalfa is a legume like clover, peanuts and soybeans. It’s a class of plant that has a different root structure than grasses and grains, providing legumes with improved nutrient content. For example, alfalfa contains two to three times more protein and calcium than grass hays and usually provides more beta-carotene (Vitamin A precursor) and Vitamin E. Pound for pound, alfalfa provides more digestible nutrients than most other forage types.
So why are people afraid of feeding it?
The Kidney Disease Myth
Some people avoid alfalfa altogether because they have heard it will cause kidney disease. This myth probably sprang from alfalfa’s effect on urine production. Because alfalfa is high in protein and because excess protein will normally be converted to urea, a horse that gets more than its share will urinate more than usual. While feeding excess protein may increase urination, it will not damage a healthy kidney. However, while kidney disease is not common in horses, if such a condition did exist, alfalfa would not be the best choice when trying to limit protein intake.
Alfalfa is also higher in calcium than grass hays. The equine kidney actively filters excess calcium so diets high in the mineral may lead to milky white urine formed by calcium carbonate crystals. This observation has led some people to believe that feeding alfalfa will cause urinary stones, though equine urinary stones are rare and are believed to be caused by a separate infection in the urinary tract and not alfalfa.
Real Causes of Colic
A primary risk of colic is a recent change in forage, no matter what its type. Alfalfa is a nutrient-dense forage and a sudden change from grass hay to alfalfa hay could certainly increase the risk of colic, but if the horse is slowly introduced to the alfalfa over a seven-day period, its intestinal microbes will safely adjust to the change.
Another rarer cause of colic is intestinal stones that are called enteroliths. Recent studies appear to show an increased risk of enteroliths with feeding alfalfa. However, studies have also shown that enteroliths are more common in certain regions of the country, leading to the theory that the magnesium content in regional forages may predispose horses in those areas to enteroliths.
What has not been examined in these enterolith studies is the total protein content in daily rations. If high-protein alfalfa is fed with high-protein grain, chances are the total protein content in the ration will exceed a healthy horse’s needs. This excess protein will produce a more alkaline pH in the horses’ hindgut and it’s plausible the change in pH could cause enterolith formation. Would we see enterolith formation if a low-protein grain concentrate was fed along with alfalfa? Regardless, enteroliths are rare, even when alfalfa is fed.
Gastric ulcers are yet another cause of colic. Research has shown that alfalfa will buffer stomach acid better than grass hay because of its increased calcium and protein, both of which are thought to have a buffering effect. If small amounts of alfalfa were fed on a continuous basis, would we see a lower incidence of equine stomach ulcers?
Finally, in certain regions, blister beetles are rarely found in alfalfa. When ingested, just a few of these bugs can cause severe colic and death. Fortunately, hay producers have learned how to minimize the incidence of these dangerous insects.
Performance and Show Horses
Some nutrition experts have said that optimal performance cannot be attained as long as alfalfa is fed. This assertion doesn’t hold water with a few of the top Triple Crown trainers. Some of them have roots in Quarter Horse racing where feeding alfalfa is the norm. These trainers feel that feeding high-quality alfalfa is more palatable than regular forages and helps maintain body condition.
Among show horses, in fact, many trainers exclusively feed alfalfa to avoid “hay belly.” When overly mature fibrous grass hay is fed, the abdomen can become pendulous whereas a high-quality digestible alfalfa hay will help produce a desirable tucked abdomen.
COPD or Heaves is an allergic reaction to dust and mold in the airway. The most common sources of dust and mold are forages harvested in regions with typically high humidity. Alfalfa often gets blamed for causing these allergies when, in fact, the horses are reacting to the dust and mold found in the alfalfa hay.
The question as to where the best alfalfa comes from is a tricky one. In dry climates, alfalfa leaves (the most nutritious part of the plant) are prone to break off at the stem during harvesting, so that if the alfalfa is baled during very dry conditions there can be excessive leaf loss. If alfalfa is baled when it’s overly moist, it is prone to creating dust and mold. Therefore, some of the best alfalfa is harvested in arid climates where moisture is controlled through irrigation.
Alfalfa is Just Too Expensive
In certain regions of the country, the primary horse forage is alfalfa cubes. Alfalfa cubes are comprised of long-stem fibers, unlike alfalfa pellets, which are short in fiber length and do not provide enough chewing time. For this reason, alfalfa cubes are preferred over pellets and are an excellent forage supplement. While some people avoid using cubes for fear of choking and wood chewing, horses that are fed the cubes in tubs and are slowly acclimated to it, show no increased risk of choking.
Though these products cost more per pound than grass hay, they may offer a better value. Sometimes fewer pounds of grain are needed to maintain body condition with high-protein alfalfa products. Similarly, if these alfalfa products are fed as a forage supplement, they can improve your total ration without the cost of total hay replacement. In evaluating the cost, determine the value of having a nutrient-dense forage to achieve optimal body condition and performance.
High-quality alfalfa offers many nutritional advantages over grass hay, but it must be managed properly and balanced with the appropriate grain ration. Once that balance is reached, your horses will show you that there is no reason to fear this misunderstood forage.