Equine diets: Forage Subsitutes

Something to chew on 
Forage is a staple in any horse’s diet, and the best sources are natural grasses and hay. But if your horse has special needs, here are 8 alternatives for consideration.

by Kerri-Jo Stewart, BPE, MSc as published in Equine Wellness, Vol 7, issue 1; Jan/Feb 2012 

Horses rely on a fairly continuous source of forage as their sustenance. In fact, at least 50% of their diet needs to consist of forage. Natural grasses and legumes can fill all the nutritional requirements for horses, and the fiber is needed to maintain a healthy digestive system. Hay is the common alternative when natural forage is unavailable. Unfortunately, good quality hay is not always easy to find, which means forage substitutes may be required. The most difficult challenge with a forage substitute is to ensure adequate fiber and roughage. It appears there’s a relationship between behavioral issues and the time a horse spends chewing. Usually, the first problem to develop is wood chewing; tail chewing is also not uncommon. It’s believed that a certain amount of saliva production is necessary to act as a buffer in the hindgut. Reduced saliva production from decreased chewing time means digestive tract functionality is compromised. Here are eight possible alternatives to feeding hay, along with their pros and cons.

1. Hay cubes Hay is forage that is cut, sun cured and baled. For hay cubes, the forage can be either sun cured or dehydrated. Typically using timothy, alfalfa, or a combination of both, the forage is cut at an early stage of maturity and only partially dried in the field before being shipped to the processing plant and dehydrated. Then, instead of baling, it is coarsely chopped, mixed with a binder, compressed and set into a form. Different manufacturers use different supplements and binders which are listed on the label. Types and amounts of protein, minerals, molasses and oils all vary between brands, as does the caloric content. Check for the mixture that best matches your feeding needs. There are some noted advantages to feeding the cubes over hay1. The processed cubes have lower moisture content, less mold and spores, and stay better longer, retaining their nutritional profile. They are easier to store and can generate less waste than hay. The nutritional profile is more uniform and the values are displayed on each bag. They can also be easier for older horses to chew, and may be more digestible. Soaking the cubes for easier chewing or for highly sensitive animals is also simpler than soaking hay, and may result in less dust and mold. For horses on special regulated feeding programs, it’s easier to monitor how much has been consumed with pellets or cubes than it is with hay. On the downside, cubes are more expensive than hay because of processing costs, and horses finish them faster so spend less time chewing. It’s suggested that an appropriate type of hay is fed along with the cubes to prolong the feeding (a half to one pound daily). Also, you can’t see the purity of the feed because everything is ground together and looks the same. While some horses don't like the texture of cubes, others may wolf them down, which means those predisposed to choke or digestive problems should have their food soaked. Because cubes are in a compact form, you need to guard against overconsumption. In several research studies at Rutgers, Ralston reports good results from using hay cubes as the sole source of fiber2. Although they found an increased incidence of wood chewing in every study, Russell and Johnson3 reported that cubes made from coarsely chopped hay appeared to eliminate wood chewing. Care needs to be taken when switching over from hay to a cubed feed. As with any change of feeding regime, it needs to be done slowly over time. In general, the cubed feed can be fed in the same amounts as hay, based on weight. Start by gradually adding the new feed in, and eventually feed up to 75% to 80% cubes over hay by weight5.

2. Hay pellets Pellets go through the same manufacturing process as cubes, but they also go through a more intense grinding process. Again, different manufacturers use different mixes, binders and supplements as detailed on the labels. However, because of the smaller particle size of pellets, they have not been found to maintain a healthy digestive system. Pellets have also been linked to behavioral issues such as wood chewing and tail biting2 as well as increased searching and non-restful behavior6. A minimal recommendation is to feed 1% of the horse's body weight per day with hay; however, that may not be sufficient. Pellets are not recommended as a complete forage substitute6. 3. Haylage When creating haylage, forages are harvested at moisture levels between 45% to 70%, then stored in a container such as a plastic bag. The exclusion of air and the resulting low pH is required for preserving high-moisture forage. However, the risk of spoilage and toxic development during fermentation is very high for horses. Horses that are going to be fed haylage should be vaccinated against botulism2. Many people have used haylage to feed their horses, but how many fatalities there have been isn’t known. Research is also lacking about the effects of feeding a highly acidic feed to horses. When haylage is exposed to air for feeding, it needs to be quickly consumed and should be monitored to ensure there is no mold or spore development3. Moving bales must be done carefully, as any tears or holes in the bag will cause a secondary fermentation and spoilage. Haylage should be used very cautiously if it is needed as a forage replacement. Also, because of the high moisture content, more haylage needs to be fed on a per weight basis than compared to hay.

4. Beet pulp Beet pulp is a very digestible source of fiber. Because of the high fiber content it is considered a long-stemmed forage substitute. It is a popular supplement because of its low sugar content, high calcium and moderate protein levels (8%). In general, one pound of beet pulp is fed for every one-and-a-half pounds of hay that it replaces. When used as a hay substitute, beet pulp shouldn't make up more than 40% of the total forage. That’s because it doesn’t provide the long-stemmed forage component required for gut health. The traditional form has to be soaked, but the new pelleted form doesn't. Up to ten pounds (dry weight) of beet pulp can be fed to an average mature horse, but he will also need a balanced vitamin/mineral supplement since beet pulp doesn't contain vitamins. Some horses will also require additional protein.

5. Bran Although wheat bran is often fed as a fiber supplement, it is not beneficial to horses, especially in large quantities over long periods of time. Bran has an inverted calcium to phosphorous ratio that can cause imbalances, as well as debilitating problems from the high phosphorous content. Rice bran has also been promoted as a source of fiber and energy (fat) for horses. However, rice bran has an even higher concentration of phosphorous than wheat bran. Neither rice nor wheat bran are recommended as a forage substitute2.

6. Chaff Chopped hay and straw is known as chaff. Chaff can provide indigestible fiber essential in maintaining digestive tract health. It may also be used as something the horse can chew for an extended period of time. The quality of chaff can often be a concern, so it is important to check that it’s not contaminated with any molds or other substances that could be toxic to horses.

7. Complete feeds Concentrates are sold as “complete feed” and some are labeled as a complete forage substitute. They can contain a mixture of hays, grains, beet pulp, and vitamin and mineral supplements, and are developed around various standard nutritional profiles (i.e., growth, maintenance, performance, broodmare). However, complete feeds don't have the required fiber to maintain a horse's health. It’s better to use them as a supplement to forage, not as a complete replacement.

8. Straw Straw is the stalks remaining after harvesting a grain crop. It contains very little nutritional value but can be a good source of fiber. Straw may satiate a horse's desire to chew when he is restricted from adequate sources of long-stemmed forage or sufficient fiber. Straw is not a source of nutrition.

Summary The only true forage substitute for hay is hay cubes. The best hay cubes for supplementation are the ones with long-stem fiber of at least an inch in length. Pelleted feed, beet pulp and complete feed can be great nutritional products but don't replace the long-stemmed fiber required for intestinal health. Straw can be added as a fiber source if no hay is available. The increased consumption of dense, higher energy forage substitutes over hay can be a benefit or a drawback depending on the type of feeding requirements your horse has. Overweight horses on a restricted diet need sufficient nutrients. Processed feeds with nutrient details on the labels make it easier to manage and monitor nutrient intake. At the other end of the scale, hard keepers are more likely to consume more feed overall with cubes or pellets (up to 25% more over hay3), and better maintain their weight. An animal unable to maintain a healthy body condition can be having dental or other problems to do with his ability to intake feed (pituitary problems, pain, or herd competition7), all of which should be looked into. Soaked hay cubes, beet pulp and/or complete feed can add needed nutrition in an easier to consume form.

1. Kentucky Equine Research, Inc, “Nutrition and Convenience in Cube Form”, Equinews, vol.9:2, www.ker.com/library/equinews/v9n2/v9n203.pdf.
2. Ralston, SL, Wright, B., Forage Substitutes For Horses, Government of Ontario, Ministry of Agriculture, Food and Rural Affairs, 2008, www.omafra.gov.on.ca/english/livestock/horses/facts/05-055.htm.
3. Russell, Mark A., Department of Animal Sciences and Johnson, Keith D., Department of Agronomy, Cooperative Extension Service, Purdue University, Selecting Quality Hay for Horses, http://www.agry.p­urdue.edu/ext/forages/publications/ID-190.htm
4. Coleman, RJ, Lawrence, LM, Henning, JC., Alfalfa Cubes for Horses, University of Kentucky, www.uky.edu/Ag/AnimalSciences/pubs/id145.pdf.
5. Johnson, Debra, “Feeding horses hay cubes”, http://horsehints.org/HayCubes.html.
6. Elia, JB, Erb HN, Houpt, K., “Motivation for hay: effects of a pelleted diet on behavior and physiology of horses”, Physiol Behav. 2010 Dec 2;101(5):623-7.
7. Jarvis, NG. Nutrition of the Aged Horse. Veterinary Clinics of North America: Equine Practice Volume 25, Issue 1 , Pages 155-166, April 2009
8. Kentucky Equine Research Center: Kentucky Equine Research Staff · October 27, 2011