When it comes to any grain sources that may be added to your horse’s diet, fiber plays a much smaller role since the amount of fiber that is added by grains is relatively little, but the effect and digestive process is similar.
When feeding the grain portion of the diet, ensure that your horse is not receiving high quantities of grain meals all at once – typically no more than 5-6 pounds of grain per meal at most. Because grains tend to be higher in starch than roughage, feeding too much at once can overwhelm the small size and quick rate of passage of food through the stomach and small intestine, and allow starches to pass undigested to the hindgut. Digestion of starches in the hindgut releases lactic acids that are toxic to the fiber-digesting microorganisms, which can result in a gas colic episode or laminitis.
Generally speaking, when you look at a the tag from a basic equine ration, the higher the crude fiber level listed, the lower the energy content of the feed. Of course, there are other factors that must be looked at, such as the fat level, and also possibly the sources of fiber.
Beet pulp, for example, is often referred to as a “super-fiber” due to the high level of fiber it provides while also providing roughly the same energy level as oats. While soy hulls and dehydrated alfalfa are common ingredients used to increase fiber levels, a performance horse ration with a higher fiber level may make use of beet pulp to achieve both increased energy and increased fiber levels.
Question: We’ve finally purchased a horse property! It’s 7 acres with about 5 acres in pasture. We have 2 horses, but are looking to expand our herd. However, we do not want more horses than what our pasture can hold since we do not want to feed hay (or much hay) during the summer. How many horses can our pasture support?
Response: Congratulations on purchasing a horse property! The answer to your question is, “it depends”. In general, 2 acres per one 1,000-pound horse is recommended if owners expect the pastures to provide most of the horse’s nutrition during the growing season. However, this is highly variable and depends on several factors including geographical location, soil type, rainfall, and management. Although location, soil type, and rainfall are mostly out of an owners control, management can be controlled and includes mowing, fertilizing, controlling weeds, resting (e.g. avoiding over-grazing), and dragging; all recommended best practices for horse pasture management.
Your 5 acres of pasture should be able to feed 2.5 1,000-pound horses during the summer grazing season. If your farm is on sandy soil, there is a drought, or you choose not to do any pasture management (e.g. mowing, fertilizing, weed control, resting, and dragging), then 5 acres might not be enough for your two horses and hay supplementation would be needed. On the other hand, if your farm has heavier soil, there is good rainfall, and you practice good pasture management, then your pasture should be able to support your two horses, and maybe one more, during the summer grazing season. For more information on pasture management, click here.
Author: Krishona Martinson, PhD, University of Minnesota. Photo credit: Michelle DeBoer, PhD, UW-River Falls.
It is tempting to turn horses out into spring pastures at the first sight of green grass, especially after a long winter. However, spring grazing should be introduced slowly and delayed until grasses reach 6 to 8″ to optimize both the health of the horse and pasture. When horse pastures reach 6 to 8″, begin grazing for 15 minutes, increasing the grazing time each day by 15 minutes until 5 hours of consecutive grazing is reached. After that, unrestricted grazing can occur.
Why is this recommendation so important? Even though hay and pasture are both forms of forages, there are significant differences. Dried hay is approximately 15% moisture compared to fresh pasture that is 85% moisture. The horse is a hind-gut, fermenting herbivore that relies extensively on the microbes present in its gastrointestinal tract to be able to process forages. The microbes are a mix of different organisms that work together to the benefit of the horse. If the feedstuffs the microbes are utilizing change suddenly, there may be too little time for the microbial populations to adjust to the change. Instead, large numbers of them die, while others flourish, setting up a situation where toxins may be absorbed by the horse, resulting in digestive dysfunction and possibly colic. A gradual change from one feedstuff to another provides enough time for the microbial populations to adjust.
Additionally, pasture grasses need sufficient growth before grazing is allowed. Photosynthesis (the process of converting solar energy to chemical energy) occurs mainly within the leaves of plants. If the leaves are grazed too early (prior to 6″ tall) or too often, plants can lose vigor, competitiveness, and root structure due to the lack of photosynthetic ability. This will lead to eventual die back and overgrazed areas being replaced by undesirable plant species or weeds. Grazing should cease when forages have been grazed down to 3 to 4 inches. At this time, move horses to another paddock or a dry lot. Grazing can resume when grasses regrow to 6 to 8″. On average, about 2 acres of well-managed pasture can provide the forage needs for one horse during the grazing season.
It is critical to slowly introduce horses to spring pastures. So, the following is worth repeating, when horse pastures reach 6 to 8″, begin grazing for 15 minutes, increasing the grazing time by 15 minutes each day until 5 hours of consecutive grazing is reached. Following this recommendation will help ensure both horse and pasture health.
Author and photo credit: Krishona Martinson, PhD, University of Minnesota
Most universities and equine nutritionists encourage horse owners to have their hay tested. However, most horse owners need help interpreting the results of their analysis. Below is a list of some of the primary components commonly analyzed for in hay, and a basic interpretation of each. Keep in mind that additional components can be analyzed for by request (and/or for an additional cost) and that each laboratory will have a unique display of results. Also, remember the analysis you receive is only as good as the sample you submit. For more information on taking a hay sample, click here.
As Sampled vs. Dry Matter Results
When your sample is returned, there will be two main columns of numbers; As Sampled and Dry Matter. As sampled reports nutrients in their natural state, including moisture. Dry matter reports nutrients with the moisture removed. Results reported as dry matter allow for the direct comparison of nutrients across different feeds and often simplifies the ration balancing process; therefore, we recommend owners use the percent dry matter column. In this example, this is the third column of numbers.
Moisture The optimum moisture for horse hay ranges from 10 to 15%. Hay under 10% may be too dry, leading to brittle hay. Hays over 17% moisture have an increased risk of molding (unless propionic acid is used), and hays over 25% moisture pose the threat of severe heat damage and serve as a potential fire hazard. In the above example, the moisture of this hay is 7.8% (moisture is usually listed above the other components at the top of the report). Please note, this hay was used for a research trial, so was dried prior to analysis.
Equine Digestible Energy (DE) DE is the measure of the digestible energy in the hay and is used to balance the energy portion of the equine diet. Most hays range from 0.76 to 0.94 Mcal/lb of DE. Different classes of horses require different amounts of DE. For example, a light working horse requires approximately 20 Mcal/day of DE. In the above example, the hay has 0.92 Mcal/lb of DE. If this hay was used to feed a horse in light work, 22 pounds of hay each day would be needed to meet the horse’s energy requirement (20 Mcal/0.92 Mcal per lb/= 22 pounds). Make sure you request an equine DE when having horse hay analyzed as sometimes the default DE calculation is for cattle.
Crude Protein (CP) Crude protein is a measure of the protein concentration in the hay. Crude protein can range from 8 to 14% in grass hays, 14 to 17% in mixed hays, and 15 to >20% in legume hays. Hay containing approximately 12% CP is thought to meet the amino acid requirements of most adult, idle horses. Other groups of horses (e.g. lactating mares, horses in heavy work, and foals) require greater amounts of CP. If feeding hay with less than 12% CP, supplemental protein sources will likely be required. In the above example, the hay has 15.1% CP.
Acid Detergent Fiber (ADF) ADF represents cellulose and lignin, the highly indigestible fractions of plant material. The lower the ADF value, the more digestible the nutrients in the hay are. Hays with ADF values of 30 to 35% are readily digested, while those above 45% are appropriate for feeding horses with lower energy needs (e.g. horses at maintenance). In the above example, the hay has 35.9% ADF and nutrients should be readily digested by the horse.
Neutral Detergent Fiber (NDF) NDF is a measurement of the insoluble fiber and is classified as cell wall or structural carbohydrates. These components provide the plant with structural rigidity. The higher the NDF, the less a horse will consume; it is generally accepted as an indicator of preference. NDF levels between 40 and 50% represent hays that will be highly palatable, while those above 65% will likely not be readily consumed by most horses. However, high NDF hays can be used as “busy hays”. Both ADF and NDF can be used to help determine maturity; the higher the values, the more mature that hay tends to be. In the above example, the hay has 64.8% ADF and will likely be more slowly consumed by horses.
Non Structural Carbohydrates (NSC) NSC is an analysis of the starches and sugars in the forage. NSC is commonly estimated by adding starch and water-soluble carbohydrates (WSC). Since some horses are very sensitive to dietary starch and sugar (e.g. horses with laminitis and metabolic syndrome), the NSC level can be helpful in selecting hay. Hays containing greater than 12% NSC should not be fed to horses diagnosed with metabolic syndromes, while NSC is rarely a concern for healthy horses. In the above example, there is 5.3% WSC and 0.9% starch for an estimated NSC of 6.2%. This example is teff hay, an annual warm-season grass becoming popular among owners managing laminitic and metabolic horses.
Calcium (Ca) and Phosphorus (P) Ca and P are two macrominerals required in the diet by all horses in specific amounts. The levels of these minerals can vary among different types of hay. For example, legume hays have high Ca levels relative to P. For the adult, maintenance horse, the Ca:P ratio should be between 3:1 to 1:1. In the above example, the hay has 0.44% Ca and 0.39% P for a Ca:P ratio of 1.13:1. Additional minerals can be tested for if necessary.
Relative Feed Value (RFV) RFV can be used when selecting hay but is not used in balancing equine rations. Generally speaking, higher RFV reflects higher quality, greater intake, and digestibility. An “average” hay has a RFV of 100 and most agree would be suited for horses in light work. In the above example, the RFV is 87% indicating this hay would be best suited for adult horses at maintenance.
Weather woes; winter injury, a cool and wet spring, flooded hay fields, and frequent rainfall have tightened already short hay supplies in the Midwest, and other areas of the country are facing similar challenges. Flooded fields may have long-term damage from standing water and forage quality will likely take a hit as wet conditions delay cutting. However, horse owners still need to secure hay and should consider these strategies to optimize and stretch hay supplies.
a good relationship with at least one horse hay suppliers. Find (and keep) hay suppliers that are trustworthy, communicate
well, and produce a quality product. A good hay supplier should be willing to
patiently answer questions; stand behind their product; and clearly explain
their pricing, delivery, and storage structure. In turn, owners should become
educated buyers, be aware of local conditions and prices, and be prepared to
buy when the forage is available. Both parties should be understanding of
weather conditions, be timely with communications, and be professional at all
2. Maximize pasture during the summer months. Utilizing pasture forage is usually a third the cost of feeding hay. Therefore, horse owners are encouraged to establish new pastures and maintain existing pastures. Pasture maintenance includes mowing, fertilizing, resting to allow for re-growth, dragging, and controlling weeds. Consider using annual forages like teff and annual ryegrass to extend the grazing season into the spring and fall.
3. Purchase hay by weight.Bale density can make bale weight estimations difficult, especially for large round and square bales. Most truck stops and gravel pits have scales and will allow loads to be weighed for a fee. Owners can use bathroom or luggage scales to weigh small square bales. For example, a 35-pound square bale sold for $5 is more expensive ($286 per ton) than a 50-pound bale sold for $6 ($240 per ton). Weighing the bales can also help owners accurately calculate annual hay needs.
4. Buy a
hay type that matches your horse’s needs. In general, less mature forages are more nutrient dense than more
mature forages. Likewise, legumes (e.g. alfalfa) tend to be more nutrient dense
than cool (e.g. orchardgrass) and warm-season (teff) grasses. A mature grass
hay will likely meet the needs of a pasture companion. However, feeding a
pasture companion an immature alfalfa hay may result in overspending and horse
weight gain. Always buy good quality hay with no mold, dust or weeds. Buying
hay with preservatives (e.g. propionic acid) is safe for horses and will help
limit mold growth in hay.
5. Have your hay tested for quality.Testing your hay will aid in feeding precision, costs about $20 per sample, and results are usually available within a few days. Choose a lab that has an “equine package” and provides equine digestible energy (Equine DE). Use the test results to calculate how much hay each horse needs to avoid over or under feeding. For example, an average grass hay may contain 0.91 mega calories (Mcals) per pound compared to a mixed grass legume hay with an average of 1.06 Mcals per pound. If an adult horse requires 16 Mcals each day, an owner would feed 18 pounds of the grass hay compared to 15 pounds of the mixed hay to meet the horse’s energy requirements. If these hays are the same price per ton, the mixed hay would be a better buy since less of it is needed to meet the horse’s energy requirement. Of course other nutrients are important, but energy is the first nutrient used to balance a horse’s ration.
6. Do not over (or under) feed.Most horses should eat 1.5 – 2.5% of their bodyweight (BW) in feed (forages plus grains) daily. For example, a 1,000-pound horse should eat 15 – 25 pounds of feed daily, with a majority (≥75% for most horses) of that being forage. Most horse owners should target 2% BW; however, owners with easy keepers or overweight horses should target 1.5% BW, while owners with hard keepers should target 2.5%. Overfeeding can result in excessive horse weight gain, related health issues, and wasteful spending. Using these values can also help owners accurately calculate annual hay needs.
7. Always use a feeder or net to reduce hay waste. When feeding small square bales indoors, 7% hay waste occurred without a feeder vs. only 1% with a feeder. When feeding small square bales outdoors, 13% waste occurred without a feeder vs. 1 to 5% waste with a feeder. When feeding round bales outdoors, 57% waste occurred without a feeder compared to 5 to 33% waste with a feeders. Although feeders can be an investment, all feeders paid for themselves within one year. Not using a feeder can result in thousands of dollars of wasted hay (and money) annually.
8. Reduce hay waste with proper bale wrap and storage. Research found that when harvesting and storing round bales outdoors, dry matter (DM) losses were nearly 20% for bales wrapped with sisal twine, 11% for plastic twine, 7% for net wrap, and minimal losses with B-Wrap®. Hay stored indoors will always result in less DM loss compared to hay stored outdoors; however, not all owners have sufficient indoor storage. When round bales were stored outdoors without cover, DM loss was 7 to 49%, compared to only 2 to 6% when stored indoors. Outdoor storage tips include covering the bales with tarps, deterring wildlife from storage areas, storing bales on a well-drained surface or pallets, baling or buying a tightly packed bale, and using older bales first. Consider building additional indoor hay storage to reduce losses and to help ride out market swings and the seasonality of hay production. Properly stored hay will keep for multiple years.
9. Explore using alternative feedstuffs. These can be economical compared to hay during times of high hay prices. Hay cubes, hay pellets, chopped alfalfa, and complete feeds can be used as total replacements for hay; however, horses tend to eat these products quickly. Other fiber sources include rice bran and beet pulp. These feeds cannot fully replace hay, but can be used as partial hay replacements. Whenever hay alternatives are used, owners should work with an equine nutritionist (and their veterinarian if needed).
10. Consider reducing herd numbers by rehoming horses that no longer meet your goals. A 1,000-pound horse, eating 20 pounds of hay daily, will eat about 7,300 pounds or 3.6 tons of hay annually. If hay is selling for $300 per ton, that is a cost of $1,080 annually.
Authors: Krishona Martinson, PhD, Hannah Lochner, BS, Jessica Prigge, BS, and Marcia Hathaway, PhD, University of Minnesota. Photo credit: Krishona Martinson, PhD, University of Minnesota. This and other horse nutrition articles can be found at http://www.extension.umn.edu/agriculture/horse/nutrition/.
horse pasture has several maples trees. I was told they are toxic to horses,
but our horses seem fine. Are they toxic? If they are, do we have to remove
them from our pasture?
Answer: Wilted (not fresh) maple leaves are toxic to horses. However, horses must eat 1.5 to 3 pounds of wilted maple leaves per 1,000 pounds of bodyweight to become sick. Wilted maple leaves can remain toxic for four weeks, but they aren’t generally believed to retain toxicity the following spring. Thus, illness normally occurs in the fall when normal leaf fall occurs.
Illness from maple leaves has only been reported in horses. Common signs after the first day of eating leaves include depressed behavior, tiredness, not eating, and dark red/brown urine. Signs may progress to going down with labored breathing and increased heart rate before death. Don’t cut down maple trees in horse pastures. Instead, keep branches out of reach of horses (for example, trimmed above their reach) and fence horses out of areas with a lot of wilted maple leaves. However, horses will rarely choose to ingest wilted maple leave unless very hungry. For more information on wilted maple leave toxicity, click here.
can be a beautiful time of year for horseback riding. However, frost can
negatively impact horse health during fall grazing.
There are no reports of toxicity of
horses grazing frost damaged pastures (includes grass and legume species).
However, frost damaged pastures can have higher concentrations of nonstructural
carbohydrates, leading to an increase in potential for founder and colic,
especially in horses diagnosed with or prone to obesity, laminitis and Equine
Metabolic Syndrome. To help prevent these health issues, wait up to a week
before turning horses back onto a pasture after a killing frost. Subsequent
frosts are not a concern as the pasture plants were killed during the ﬁrst
Why do nonstructural carbohydrates increase during the fall? During
the day, plants carry out the process of photosynthesis. In this process, they
make carbohydrates as an energy source for the plant. A second process,
respiration, is carried out when the plants use up the carbohydrates they
produce during the night for energy. Plant respiration slows down when
temperatures are near freezing. As a result, the plants hold their
carbohydrates overnight. Freezing can stop respiration and lock the
carbohydrates in the plant for over a week. Thus, plants tend to contain more carbohydrates
in colder temperatures or after a frost. Often, horses will prefer forages
after a frost due to the higher carbohydrates levels.
For more information on fall health concerns for grazing horses, click here.
regular hay supplier applied a preservative (propionic acid) to the bales this
year. What is that and is it safe for horses?
Answer: Preservatives are commonly used during times of frequent rainfall or poor drying conditions (e.g. high humidity or heavy dew). Propionic and acetic acids are commonly used hay preservative that are applied to hay as it is baled to allow baling of wetter than normal hay without spoiling during storage. Moisture at the time of baling is directly related to mold formation. Hay baled at ≤15% moisture is unlike to mold; however this is impacted by bale-type and mass. For example, small square bales can be baled up to 18% moisture with limited risk of mold formation; however, large round bales must be baled at ≤15% moisture to reduce the risk of mold formation. Preservatives are most effective at inhibiting mold growth, and most economical, when the hay is baled between 18 to 25% moisture.
Preservatives are safe for use in
horse hay. Researchers found that when given a choice, horses preferred hay
that was not treated with a preservative; however, horses readily consumed the
treated hay when a choice was not given. Yearlings receiving hay treated with a
preservative consumed and gained just as much as yearlings consuming untreated
hay, and clinical measures of well-being were not affected by consumption of
preservative-treated hay. Interestingly, a horse’s hindgut bacteria actually
make propionic acid as a result of microbial fermentation.
Therefore, feeding horses hay treated with a preservative is a safe and common practice, especially in years when poor weather conditions exist for making hay, and helps to inhibit mold growth during storage.
Question: This spring, we planted 2.5 acres of pasture for our horses. The grasses are now 6 inches tall and the stand density appears good. Should we mow the pasture? If so, how often? When should we start grazing?
Answer: You will want to mow the pasture 3 times before allowing the horses to graze. Since the grass is 6″ tall, mow it down to 3″ and allow it to re-grow to 6″, then mow again. Follow this cycle until you have mowed the pasture 3 times. This is critical since new grass seedlings need time to firmly root into the ground. Mowing helps to stimulate root growth and anchors the plant without the physical pressures of grazing. If the pasture is grazed too soon, horse can pull new grass seedlings out of the ground. Mowing will also help control some weeds that are common in new pasture seedings.
Once you have mowed 3 times and the
grass has regrown to 6″, you can start grazing the horses. If the horses
are acclimated to pasture, they can be allowed to graze until the pasture is,
on average, grazed down to 3″. At this time, you would rotate the horses
off the pasture, mow the pasture to 3″, allow the pasture to regrow to
6″, then graze again. You would keep repeating this process until the
pasture stops regrowing in the fall; it is critical to allow the pasture to
rest and regrow. Unfortunately, horses do not graze uniformly, so mowing is
necessary to ensure the pasture regrows evenly, plus mowing will help control
If your horses are not acclimated
to pasture, then start grazing in 15 minutes increments, adding 15 minutes each
day until you reach 5 hours of consecutive grazing. For example, 15 minutes on
day 1, 30 minutes on day 2, 45 minutes on day 3, etc. This allows the horses to
slowly acclimate to pasture and reduces the risk of laminitis and colic that is
often seen with abrupt diet changes.
Along with mowing, make sure to drag manure piles 2 to 3 times a
year during hot and dry times, fertilize as needed, and control weeds. For more
information on pasture management, click here.