How Do Pelleted Horse Feeds Stack Up?

Nourishing horses for various life stages and diverse athletic endeavors first requires choosing appropriate feedstuffs. When forages cannot meet all nutritional requirements, diets must include a concentrated source of energy and other essential nutrients. These concentrates come in many forms, the most popular of which are textured, pelleted and, to a lesser extent, extruded.

Textured, also known as sweet feeds, muesli, or coarse mixes, are characterized by their loose nature in which the various ingredients can be differentiated from one another. Cereal grains such as oats, barley, and corn can be easily distinguished from other ingredients, such as beet pulp or molasses. Palatability of textured grains is high among horses, often due to molasses, so why would feed manufacturers wish to pellet feeds?

According to Peter Huntington, B.V.Sc., M.A.C.V.Sc., director of nutrition for Kentucky Equine Research Australia, “feed manufacturers pellet feeds to combine high-quality ingredients that may be in a milled or meal form such as protein sources, minerals, or grain coproducts to create a uniform feed.” Soybean meal, for example, is used extensively in the formulation of horse feeds because it is a rich source of protein, but manufacturers have found that it is best fed pelleted as it increases palatability.

Pelleting requires that feed ingredients be ground into small particles, mixed together, steam-heated, and then pressed through dies to form the pellet. The heat causes the natural starch in cereal grains to gelatinize, which means the complex carbohydrate bonds inherent to starch collapse, making starch more susceptible to digestive enzymes and consequently more available as an energy source for horses. “Interestingly, low-starch formulations are more easily pressed into a pellet than made into an extruded feed, as starch is integral to the high-heat expansion process that occurs with extrusion,” said Huntington.

From the manufacturer’s perspective, pelleting is an attractive process because it provides uniform distribution of all the ingredients, especially vitamin and mineral premixes. This benefit is shared by horse owners as well. “The number-one advantage of pelleting is feed uniformity, so one mouthful is the same as the next, and fine material can’t be sifted out or left in the bottom of the feed bin,” said Huntington.

In addition, pellets have several practical advantages, according to Huntington. “Because they contain very little moisture, they have a longer shelf life than textured feeds, and they are essentially dust-free. Because of the steam treatment of the ingredients, the fresh end product will be relatively free of bacterial and fungal contaminants. Additionally, pellets are relatively dense and uniform, so they can easily be stored in bulk bins or silos.”

Feeding horses depends on the horse’s willingness to eat the meal placed in front of it. “Some horse owners consider pelleting to be old technology and therefore not as appealing as newer processing techniques, like extrusion. Compared to textured feeds, pellets may be less palatable, but an ‘aged’ pellet will often be more palatable than an ‘aged’ textured feed,” explained Huntington. “When judged against extruded feeds, pellets are more palatable, especially when first introduced.”

Building on the theme of practicality, pelleted feeds offer an advantage over extruded feeds when a mash must be made, as might be necessary for senior horses with poor teeth or when horses have an aversion to nutritional supplements or oral medications. Pelleted feeds can be moistened easily, adjusting the wetness based on the preference of the horses being fed or the add-ins being used.

Further, feeding pelleted products might be advantageous for horses with certain endocrine problems. “Research has shown that pelleted feeds might be more appropriate than extruded feeds for horses with metabolic conditions,” said Huntington. “A study conducted at Virginia Tech found that extruded feeds caused greater glucose and insulin responses after the evening meal than pelleted feeds.”^* A goal of feeding many horses with metabolic conditions is to keep glucose and insulin as low as possible following meals.

A second study conducted by researchers at Texas A&M University compared the effects of pelleting and extrusion on digestion.^** The researchers found horses consumed pellets more quickly, which reflected a possible advantage in palatability. More importantly, researchers noted a significant increase in dry matter and organic matter digestibility in pelleted feeds. Researchers in Norway also found better prececal protein digestibility with pelleted grains than extruded.^*** The decided advantage of digestibility is most likely due to the improvements in pelleting technology in recent years.

Ultimately, the best feed for any horse is the one that provides optimal nutrition in a form the horse finds palatable. “Horse owners need to choose the most appropriate feed for their horses and ensure the quality of the processing is the best it can be. Whether the grains have been steam-flaked, micronized, pelleted, or extruded, it is important that the starch has had some level of gelatinization to ensure enhanced digestion,” said Clarissa Brown-Douglas, Ph.D., a nutritionist with Kentucky Equine Research.

^*Ely, K., P. Harris, K. Kaufman, N. Liburt, A. Krotky, and B. McIntosh. 2019. Digestibility and postprandial response according to processing method and meal time of day. Journal of Equine Veterinary Science 76:67.

 ^**Goehring, M.S., J. L. Leatherwood, M.D. Eggleston, A.N. Bradbery, B.J. Carillo, et al. 2017. Effect of feed processing on equine digestion. Journal of Equine Veterinary Science 52:78.

 ^***Rosenfeld, I., and D. Austbø. 2009. Digestion of cereals in the equine gastrointestinal tract measured by the mobile bag technique on caecally cannulated horses. Animal Feed Science and Technology 150: 249–258.