FEEDING WHEN HAY IS SHORT—WHAT ARE THE ALTERNATIVES?
As Presented by Dr. Alyssa Butters,
2009 Equine Services Fall Seminar
With the poor weather during the growing season this year and the widespread shortage of hay, many people have been faced with the prospect of paying for very expensive hay for their horses, or even having difficulty finding hay altogether. Therefore, a commonly heard question has become—with what can I replace hay in my horse’s diet?
So why do we feed hay in the first place? For most horses, hay should comprise the majority of their daily ration. For the average adult horse, good grass hay supplies nearly all their daily protein requirement. Most grass hays contain 9-12% protein, close to the needs of an adult horse at maintenance (10-11%). Hay also provides a good source of fibre. Although not truly a “nutrient,” horses digestive systems have adapted in environments where they graze almost continuously throughout the day, and they have a drive to consume fibre. No absolute minimal level of necessary fibre has been established, however inadequate dietary fibre can lead to increased wood chewing behavior and can increase the incidence of colic and gastric ulcers.
How much hay should be fed? Hays vary in their energy and protein content, so the bottom line when determining how much hay to feed is to have your hay tested. Protein and energy contents cannot be accurately estimated just by looking at the feed. Forage testing is necessary to determine the nutrient composition of your hay in order to assess if it is meeting the nutritional needs of your horse (see Forage Analysis handout). Once this is established, a general rule of thumb is to feed an adult horse at maintenance 2% of their body weight in dry matter intake (DMI) daily. Hay is usually about 90% dry matter by weight. For an “average” 1000lb horse, this translates to approximately 20 lb DMI, or about 22 lb of hay as fed. To simplify feeding square bales, once you have determined how much by weight you should be feeding your horse, determine the average weight of your square bales and allot the daily ration as a fraction of a square bale. Although square bales vary a lot in weight, a typical small square bale would average 50-60 lbs. For an average 1000 lab horse, they would eat 1/3-1/2 of a bale per day, spread over several feedings. Know the weight of your horse, and know the weight of your square bales.
General recommendations for when hay is in short supply:
Test your hay. Know what you are feeding so you know how much you need to feed without excess. Refer to the Forage Analysis handout for more information about how to go about testing your feed.
Group your horses. Some horses require more feed to maintain body weight than others. If it is possible to segregate them according to their feeding needs, you can reduce feed “wasted” by overfeeding the easy-doers in order to keep weight on the less thrifty individuals.
Feed from a feeder. This alone can reduce feed wastage by 20-25%, especially if the hay is very leafy, and is also better from a parasite management point of view.
Consider forage substitutes to “extend” your hay if you are having difficulty finding hay.
Provide adequate, heated water. Ideally, water available to horses in the winter should be heated to 2-10°C. A general rule of thumb is to provide 3 pounds of water for every pound of feed fed. For the average 1000lb horse eating 22lb of feed in a day, this would indicate that approximately 7 gallons or about 30 L of adequately warmed water should be available. Especially if there is snow on the ground, your horse may not drink that much, but do not count on snow to meet their water needs. Horses do seem to derive some moisture from snow, especially if they have to graze through it, but this cannot be assumed to be adequate. On a horse eating hay and not grazing, they would need to consume a large amount of snow in order to provide 30L of water, plus consider the energy required to melt the snow once ingested and heat it to body temperature. As this energy comes from their feed, it can require more feed (and therefore cost more) to not provide adequate water, and can also increase the risk of impaction colic.
What about alfalfa?
Alfalfa usually has a higher protein content than grass hays, running around 18% protein or more. This is more protein than most adult horses require. But will it hurt them? Often no. The excess protein is diverted into energy production via carbohydrates and the nitrogen portion of the protein is excreted in the urine as long as the kidneys are functioning properly. (This is the reason why you may notice your horse urinates more if alfalfa is introduced into the diet.) It does mean that alfalfa has to be fed carefully to horses that have a tendency to be on the fleshy side. They can gain weight easily on alfalfa, and if your horse is prone to laminitis or has been diagnosed with Equine Metabolic Syndrome or Cushing’s disease, alfalfa may need to be removed from the diet altogether. As the protein can be converted to precursors that enter the carbohydrate metabolism chain, it should also be avoided in horses diagnosed with Polysaccharide Storage Myopathy (PSSM), more commonly known as “tying up.” Alfalfa should not be fed to horses with kidney dysfunction.
For horses that are hard to keep weight on, alfalfa hay can be helpful. For an adult horse at maintenance, without the above-mentioned problems, an alfalfa or alfalfa/grass mix hay may certainly be appropriate. However, be sure to monitor their weight and feed accordingly.
Hay or Alfalfa Cubes
These are probably the most commonly used “hay extenders.” They are readily available in either straight alfalfa or 50% alfalfa/grass mix formulations, and are relatively easy to transport and store. They can be purchased in individual bags or large totes. These cubes, due to their alfalfa content, are usually good sources of energy, protein, and calcium. For some horses, they may have an increased choking risk, which can be decreased by soaking them for as little as 10 minutes prior to feeding. Horses tend to eat the cubes pretty quickly and they do not provide as much fibre as long stem hay, so it can lead to an increased incidence of wood chewing. Up to 15 lb or more can be fed per horse per day. However, if alfalfa cubes are fed to an adult horse at maintenance, they are usually more appropriate as a partial hay replacement as they contain more protein and calcium than required. More commonly, 2-6 lbs are fed per horse per day, especially if the hay available is poor quality. (As a crude estimate of weight, an ice cream pail of cubes usually weighs about 6-7 lbs. To be certain you are feeding appropriately, weigh your cubes to more accurately determine their weight). Again, avoid alfalfa in horses prone to laminitis, “tying up,” or with kidney dysfunction.
Like alfalfa cubes, alfalfa pellets are easy to store and transport, and are readily available. Some horses do not like the taste of alfalfa pellets, so they can be mixed with a little grain to tempt picky eaters. These are not intended to be a total hay replacement, but rather typically fed in meals of 3-4 pounds or less if they have a fibrous hay to fulfill their drive for fibre. These pellets are quite nutrient dense, so they do not need to be fed in large quantities, and they are finished quickly. They should also be avoided in horses prone to laminitis or “tying up,” etc, and should be fed very carefully to horses that are fleshy.
Complete Feed Pellets
Complete feed pellets are designed to be fed without hay, grain, or other supplements and are usually a mixture of grains, hay, and or beet pulp, plus vitamins and mineral supplements. They come in a variety of forms—pellets, textured, or extruded. These are designed to be a complete hay replacement, however the fibre content can be problematic. Whereas long stem hay is usually around 20% crude fibre, complete feed pellets are usually comprised of at most 12% crude fibre. Again, this can lead to increased wood chewing behaviour, as well as an increased risk of gastric ulcers and colic. If it is fed as a complete hay replacement, it usually requires 12-15 lbs of complete feed per day to meet the nutrient requirements of the average 1000 lb adult horse at maintenance. If this were split into 2 feedings, it would overwhelm the horse’s digestive capacity and could led to colic and/or laminitis. It therefore has to be split into smaller amounts (ideally 2-3 lbs/feeding) to optimize digestion and to keep the horse more occupied as it is consumed very quickly. In order to feed 12-15 lbs per day, this would require 5-6 feedings, which can be prohibitively intensive. If switching to a diet composed mainly of complete feed, make the change gradually (one week minimum) to allow the horse’s digestive tract to adapt. They can be very useful as a hay extender in smaller quantities, and the bags should come with a guaranteed analysis tag that will allow you to balance your horse’s ration in combination with your hay and other feedstuffs (see NRC Nutrient Requirements of the Horse website).
Greenfeed is oat, barley, or wheat cereal crop cut in the dough stage before full maturity, dried in swathes, and baled (usually in round bales) with the grain still on the stalk. Look for oat greenfeed (also known as “oat hay”), as barley and wheat can have awns on the seed heads that can cause serious mouth ulcers. Greenfeed is best suited to mature horses. It is a good source of digestible energy, but horses on greenfeed will need to be provided with a good mineral supplement. Like alfalfa, the energy content of greenfeed makes in unsuitable for horses with Cushing’s Syndrome, Equine Metabolic Syndrome, or those that have previously foundered. It can also cause soft stools in some horses. If the feed is stressed (either by drought or, more commonly, frost), it will accumulate nitrates in the plants. There is no way of knowing what the nitrate levels are at by looking at it, so it needs to be tested. Nitrates in feeds fed to horses should be less than 0.50%.
Haylage or Silage
Although haylage is not commonly feed in this part of the country, we do occasionally get questions about feeding silage to horses. To make haylage or silage, the hay or grain is cut, partially wilted, and placed in a container with very little air, causing it to ferment slightly.
Both feedstuffs are high in energy and protein, and have the benefit of being dust-free, which makes it attractive for horses with respiratory problems (for example “Heaves”). They both, however, have to be fed very carefully, especially silage, because the high energy content can make them prone to laminitis. It is best for mature horses when it makes up no more than 50% of their dry matter intake.
Feeding haylage and silage also carries other disadvantages. Both feeds are heavy, making it more difficult to transport and feed. For wrapped bales of haylage, if the bag is pierced, it will spoil. Similarly, once a bag of haylage is opened, the entire contents have to be fed within 4 days due to the rapid spoilage that occurs once the feed is exposed to oxygen. There are unanswered questions as well about the effect of feeding acidic feed to horse, and speculation that it may increase the risk of colic.
Significantly, there is also a risk of botulism in horses fed silage or haylage. Because the bacteria that produce botulinum toxin grow in areas with no oxygen, they can thrive in the low-oxygen environment that is necessary to produce the fermentation that results in silage and haylage. It is recommended that all horses that will be fed haylage are vaccinated against botulism before being introduced to the feed.
What is beet pulp? It is the fibrous material left over after sugar is extracted from sugar beets. It is most commonly sold in pelleted form, although shredded beet pulp can also be found.
Beet pulp is a good source of fermentable fibre, which is easier to digest than hay so horses are able to extract a lot of energy from it. A pound of beet pulp can provide almost the same calories as a pound of oats, but because the calories come from fibre rather than starch, it can be fed safely in larger amounts. It is fairly high in calcium, moderate in protein values (8-12%), but has very little vitamin and mineral content so horses fed significant amounts of beet pulp need to be provided a good vitamin/mineral supplement. Do not use beet pulp as a sole nutrition source.
Beet pulp is useful as a low dust feed for hard keepers, for horses with dental problems, or just to add another forage source to extend your hay. It is not without drawbacks, however. The biggest complication to feeding it is that it must be soaked prior to feeding. The idea that beet pulp pellets expand in the throat to cause the choke is probably misguided. It usually passes through the throat so fast that it doesn’t have time to expand, unless the horse has choked on it already and it is stuck in the esophagus waiting for the vet to come out and clear the blockage! More typically, beet pulp choke is a function of the particle size and usually aggressive feeding behaviour on the part of the horse (they “bolt” a large mouthful and swallow without chewing properly). Regardless, feeding unsoaked beet pulp can definitely increase the risk of choke and soaking it will reduce that risk. It is recommended that it be soaked for 8-12 hours prior to feeding. (Similarly, the concern about stomach rupture with unsoaked beet pulp may also be unfounded. The horse’s stomach has a capacity of 2-4 gallons (8-16 L), which is equivalent to 4 ½-9 ½ lbs of dry beet pulp—more than would be fed in a single meal. Additionally, food usually moves out of the stomach faster than the beet pulp can expand.)
If your horse is prone to laminitis (Cushing’s Disease, Equine Metabolic Syndrome, or previous episode of laminitis), be watchful of the molasses content added during processing. Molasses is essentially a sugar, and will provide a source of readily available energy that those horses can have difficulty with. Up to 10 pounds of beet pulp dry weight can be fed daily (with adequate vitamin/mineral supplementation), but more commonly it is fed at a rate of 2-5 lbs dry weight/day per horse.
Do not feed large quantities of wheat bran for prolonged periods of time. It is extremely high in phosphorus, which can lead to a potentially debilitating disease descriptively called “Big Head Disease,” or more technically nutritional secondary hyperparathyroidism. Wheat Bran is fairly high in protein (approximately 16%), but is actually not a large source of fibre (more in line with oats than with hay). Limit the feeding of wheat bran to no more than 1 lb per adult horse per day, and provide calcium supplementation to balance the calcium:phosphorus ratio in the horse’s diet.
Rice bran has recently become a popular source feedstuff to provide energy in the form of fat rather than carbohydrates. It is also a fair source of fibre. However, it has a higher concentration of phosphorus per pound than wheat bran, so the calcium:phosphorus ratio of the diet must be closely monitored. Some commercial products have added calcium (this seems to be a more common practice in the US than in Canada, however), but rice bran is still not recommended as a major forage substitute.
Straw is a fibre source, and provides little else. Some people will use it to give the horses something to chew on and fulfill their drive for fibre. An example would be the provision of straw bedding to horses that have their entire nutrient requirements met through a commercial complete feed. However, it is very difficult to predict intake, so it is hard to balance their ration. Horses on straw need to have very good access to water and a good mineral supplement. There is always a concern about the straw causing intestinal impactions and subsequent colic, especially when adequate water is not provided. The risk of impaction is also increased if they are suddenly provided with straw, and this can even take the form of suddenly providing fresh straw bedding to replace older, soiled bedding. Although straw can be used as a fibre source when all other nutrient needs are being met with other food sources, extreme caution must be exercised with its use.
Although not as relevant in the winter months, we usually field a few calls a year about feeding lawn clippings to horses in the summertime. Feeding horses pure grass clippings is not recommended. Because of their small particle size and high moisture content, the clippings will rapidly ferment. This fermentation increases the energy content of the feed, and therefore increases the risk of laminitis and colic in horses fed the clippings. Because anaerobic environments are created, leading to the fermentation, there is also the risk of botulism (similar to haylage). Also beware that garden refuse can contain plants that are potentially lethal to horses, including tomatoes, potatoes, and rhubarb.
Some Considerations for Round Bale Feeding
The shortage of hay this year has had more and more people looking to round bales of hay rather than small square bales. Although hay in both forms can be moldy or dusty depending on how it is put up, there is a slightly higher risk of this in round bales. Also, free-feeding of round bales (for example in a round bale feeder) can result in an increase risk of respiratory disease such as “Heaves.” Horses have a tendency to burrow in round bales in search of fine particles and leaves, tunneling deeper into the bale and therefore increasing their exposure to dust, mold, and fine particulates that is inevitably present even in very “clean” bales. Obesity is also a problem with free feeding on round bales. Ideally, if round bales are to be fed, limit feeding by forking off individual meals is advantageous from both a respiratory health and weight control standpoint. If free feeding cannot be avoided, a round bale feeder is preferable to simply placing the bale out in the field. A feeder will reduce waste by 20-25%.
Not all round bale feeders are created equally, however. The most readily available round bale feeders in this area are designed for cattle, not for horses. Those designed for horses have an elevated tray that catches leaves and small particles, decreasing the tendency to burrow into the bale. Also, the elevation of the tray makes a horse less like to catch a foot in the feeder, a common cause of often serious heel bulb lacerations. For more information, visit the Ontario Ministry of Agriculture, Food and Rural Affairs website “Round-Bale Feeder for Horses” (see the reference for the web address).
A Brief Note About Feeding in Cold Weather
Adult horses are reasonably able to adapt to cold weather. Until the temperature drops below -15°C, known as the “lower critical temperature,” most horses are able to adapt without human intervention. However, poor teeth, parasites, or disease can lower a horse’s tolerance of cold. Also, young horses (yearlings and younger) also have a decrease tolerance of cold.
Below -15°C, proper shelter and/or an increase in feed are necessary to prevent a horse from entering a negative energy balance. The cost of feed needed to return a skinny horse to normal weight is equal to or in excess of the cost of feed that would have been required to maintain a horse at a proper weight, so prevention of weight loss in cold months is sound strategy from an economic as well as a humane standpoint. As the temperature dips below -15°C, the maintenance energy requirements of an adult horse rise 2.5% for every Celsius degree of temperature decrease. This is equivalent to 2% more feed. At –40°C, an average adult horse will require an additional 10-12 lbs of feed over an above what it required at a temperature of -15°C. If the horse is free fed hay, most will normally adequately increase their intake to compensate. If they are grazing on winter pasture, be aware that if a horse has to paw through deep snow to reach forage, their maintenance energy needs can increase by 40%. Also, if the hay provided is very coarse and over-mature, the typically low energy and high indigestible fibre content of these feeds may mean that in very cold weather horses are unable to consume enough to meet their increased demands. Feed good quality hay, especially in cold weather, or consider a concentrate source to provide supplemental energy source.
Horses with a proper shelter can conserve up to 20% more body heat than those that are exposed to the elements. If the shelter is well-bedded and the horse will lie down, this limits heat loss a further 20-25%. Refer to the Ontario Ministry of Agriculture, Food and Rural Affairs website “Management and Feeding of Horses in Cold Weather” for more information and adequate shelter specifics.
As stated earlier, an adequate supply of heated (2-10°C) water is crucial to help prevent intestinal impactions in cold weather.
REFERENCES AND USEFUL RESOURCES FOR HORSE OWNERS:
Cut Costs—Feed Forage (http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/hrs3170)
Feeding Horses When Feed is Short (http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/hrs6287)
Horse Feeding Myths & Misconceptions (https://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/hrs3243)
Ontario Ministry of Agriculture, Food, and Rural Affairs
Forage Substitutes for Horses (http://www.omafra.gov.on.ca/english/livestock/horses/facts/05-055.htm)
Management and Feeding of Horses in Cold Weather (http://www.omafra.gov.on.ca/english/livestock.horses/facts/info-coldweather-man.htm)
Round-Bale Feeder for Horses (http://www.omafra.gov.on.ca/english/livestock.horses/facts/bales.htm)