Glycemic Response to Soaked Hay

Horse HayFor horses diagnosed with Equine Metabolic Syndrome, obesity, laminitis and/or insulin resistance, the need for dietary management of nonstructural carbohydrate intake is necessary. One management tool horse owners can use is regulating the glycemic response in diseased horses, which is the effect food has on blood glucose levels after a meal. Past research has shown that soaking hay for 30 to 60 minutes reduces nonstructural carbohydrate levels; however, researchers have yet to explore if hay soaking has an effect on glycemic response. Recently, researchers at Middle Tennessee State University examined how soaked hay versus non‐soaked hay affected the glycemic response in horses.

Two different hay types were evaluated both as soaked hay and non-soaked hay; prairie grass and alfalfa. Wet hays were soaked in cold water for 60 minutes and 12 healthy horses (average of 17 years and 1,207 pounds) were fed the hays. Blood samples were taken immediately at the time of feeding and every 30 minutes for 2 hours, and every 60 minutes up to 5 hours.

Researchers found that horses had a higher glycemic response to alfalfa hay compared to prairie grass hay. However, there was no difference in the glycemic response to non‐soaked or soaked hay of either type. Over time, plasma glucose levels were higher in horses fed alfalfa versus grass hay.

Researchers concluded that although the type of hay fed influenced the glycemic response, no difference in physiological glycemic response was observed in healthy horses fed non-soaked or soaked hay. Additional research is needed to determine if soaking hay has physiological merit in horses diagnosed with Equine Metabolic Syndrome, obesity, laminitis and/or insulin resistance.

For more information on this study, click here.

For more information on hay soaking, click here.

Summarized by: Devan Catalano, BS, University of Minnesota.

This article is reprinted with permission from Krishona Martinson, University of Minnesota. This and other horse nutrition articles can be found at http://www.extension.umn.edu/agriculture/horse/nutrition/.

Avoiding a Hay Belly

I’ve often heard, ‘my horse has a hay belly, what should I do differently?’ Or,” he’s really big in the belly but he doesn’t have good muscles.”   Apart from a broodmare belly, post-colic surgery effects or a parasite situation, the answer sounds like a nutritional imbalance.  The good news is, once you know what a nutritional imbalanced hay belly is and what causes it, you can make adjustments in your program and avoid it in the future.

What does it look like?

Willow has had 4 foals, and as a result, tends to show characteristics of a hay belly.

Willow has had 4 foals, and as a result, tends to show characteristics of a hay belly.

Have you ever seen a young or growing horse with a big belly while the rest of their body looks small? Or a mature horse that has a midsection that hangs low, while ribs are visible and muscles along the back and hindquarter are hard to find?  How about the ‘pregnant gelding’ situation?  All of these are describing a hay belly.  On a regular basis, you should conduct a body condition score on your horse to check for muscle mass as well as appropriate fat deposition in key areas.  It’s important to check all areas indicated, since a rib or belly check alone doesn’t provide all the information.

What causes it?

When too many low-value calories are consumed without adequate protein (including essential amino acids), the body stores the calories as energy in cells yet the needed protein isn’t available to maintain muscle mass. In the absence of adequate protein, muscles atrophy while stored energy increases. Over time, a hay belly emerges as muscle mass over the top is lost and gut size may expand.

The biggest factor is overfeeding fiber high in Neutral Detergent Fiber (NDF) while under feeding adequate levels of quality protein. NDF is a measurement of cell wall content in plants such as grasses.  As the plant matures, it builds up stronger cell walls so that it may hold itself upright.  The stronger these walls, the less digestible these cells are for a horse.  So when fed very mature hay, your horse is less able to digest that hay, as compared to hay with a lower NDF value (less mature).  In addition to being higher in NDF, the grasses also tend to be lower in the quality proteins; important nutrients for developing and maintaining muscles.

How to prevent a hay belly

First, feed the best quality hay that you can find in the correct amount for your horse’s body weight, age and activity level. The hay that is smooth and ‘leafy’ tends to have levels of NDF that are better for the horse to digest. Hay that is pointy to the touch or looks like it’s a green version of straw should be avoided as it simply offers little nutritional value for the horse.

How do I get rid of a hay belly if my horse has one?

First, check the quality and quantity of hay your horse is eating. If the quality is adequate, then it’s time to reevaluate the quantity fed.  A horse should be fed 1.0-1.75 pounds/100 pounds of body weight of hay per day.  Not a fan of math? Yea, me neither.  Here’s a quick answer: for a horse weighing 1,000 pounds, that would be between 10-17.5 pounds of hay each day, ideally divided into 2 or even 3 feedings. Check to be sure you’re not inadvertently overfeeding, or underfeeding if your horse is actually bigger than 1,000 lbs. Learn to estimate your horse’s weight accurately here.

The last piece of the puzzle is feed. Make sure that the concentrate you provide is offering adequate quality protein.  Total protein alone can’t support or develop ideal muscles.  The right balance of amino acids is needed to build and maintain muscle quantity and quality.  Look for feeds that guarantee levels of Lysine, Methionine and Threonine.  These three key amino acids are the most important for your horse. And lastly, check to be sure you’re feeding the appropriate amount of concentrate.  Feeding a balanced diet and adding some exercise to help develop muscle mass and tighten up that tummy is a great way to reclaim that belly!

Group Feeding Tips for Small Facilities

Feeding TimeWe are a far cry from a fancy operation with four horses on my property to manage.  The horses in our herd live outside in one of two paddocks with fulltime access to a run-in shed which is divided in half.  They get rotational turn out onto the pasture whenever possible.

With the variety of horses we have, our little operation is anything but simple.  And oh how they vary!  One is a 32-year-old hard keeping Arabian mare with a princess complex who has progressively lost dentition efficacy in the last few years.  Next is her 14-year-old gelding son who is an air fern, aka quite possibly the world’s easiest keeper.  Finally the two Warmblood geldings, half-brothers both in light work.  One is a 16 hand, 10-year old fair doer while his brother (12 years) just under 16 hands, tends to be higher strung and a notch or two closer to being a hard keeper than his half-brother.

We feed good quality grass hay in small squares as we don’t have the storage space, equipment or desire to feed rounds. With these parameters, in combination with our variety of personalities, feeding time can be quite….interesting.  Over time, we’ve developed some strategies for making this living arrangement work.  Here’s a few you might consider if you have a similar herd situation:

  • Divide your herd by feeding needs and behaviors
  • Separate the bully of the herd.
  • If possible, put harder keepers with harder keepers, easy keepers with other easy keepers.
  • Keep an eye over time as the herd dynamics shift, the bullies can easily become bullied and go from ideal weight to underweight if you’re not checking regularly.
  • Check body condition score on a regular basis and be prepared to move horses around if dietary needs change.
  • Provide at least as many feeders as there are horses.  More if you can. Divide the ration of hay evenly among them.  This allows those who are bullied by others the chance to get what they need.
  • While on pasture, use a grazing muzzle on the easy keepers so that the harder keepers can have sufficient time with the forage.
  • When it comes to feeding concentrate, use paddock, pasture, round pens, arena etc.  to separate the herd.  This way, those who need a different feed type (example: ration balancer versus a senior feed) can get what they need and have time to eat it.
  • If you don’t have facilities to separate during the time to feed concentrate, consider guarding the slower eater so they can get sufficient time to eat their full ration. This may add time to the chore schedule, but it will help to ensure all horses are meeting their unique nutritional needs.

Keeping multiple horses with a variety of nutritional needs in a smaller space can be a challenge.  But with a little creativity and the right tools, you can be assured everyone gets what they need.  What ideas do you have to manage the variety of horses in your herd?

Estimating Winter Hay Needs

Cooper and Ferris in a snowstorm

Question: We recently purchased a farm and will be housing our two quarter horses over the winter. They are trail horses who are not ridden during the winter. Because I’ve always boarded my horses, I’m not sure how to estimate how much hay I will need for the winter. Can you provide some guidelines?

Response: An adult horse at maintenance will consume between 2 – 2.5% of their bodyweight in feed (hay and grain) each day. For example, a 1,000 pound horse fed a 100% hay diet would consume 25 pounds of hay each day.

  • From October 15 to May 15 (when there is no pasture in MN), the horse would consume about 5,350 pounds of hay or 2.7 tons.
  • This would equal 107 fifty pound small square‐bales or six 900 pound round‐bales during this time.
  • For two horses, this amount would be doubled; 214 small squarebales or 12 round‐bales.
  • It is critical to know the weight of the hay bales; not all bales weigh the same.

If the same horse was receiving 5 pounds of grain each day, their hay needs would be reduced to 20 pounds each day.

  • From October 15 to May 15 the horse would consume about 4,280 pounds of hay or 2.1 tons.
  • This would equal 86 fifty pound small square‐bales or five 900 pound round‐bales during this time.
  • For two horses, this amount would be doubled; 172 small‐square bales or 10 round‐bales.

These estimates assume good quality hay is fed in a feeder to reduced hay waste. When feeding small squares‐bales, hay waste when a feeder was not used (hay fed on the ground) was approximately 13% compared to only 1 to 5% when a feeder was used. When feeding large round‐bales, not using a feeder resulted in 57% hay waste compared
to 5 to 33% hay waste when a feeder was used. Its always best to purchase some extra hay since horses may require additional hay during the cold winter months (depending on their access to shelter).

Author: Krishona Martinson, PhD, Univ. of Minnesota. Reprinted with permission of the author. For other topics from the Univ. of Minnesota Equine Extension, visit their website.

Small Changes in Hay Have a Big Impact on Your Horse

102_2349 (Small)You just received a new load of hay in to your barn. It smells so good, and looks just like the last load you got from your regular supplier. But is it really the same? While it might be similar, growing and harvesting conditions vary with every single cutting, and that can have an impact on the nutrition contained in that sweet-smelling pile of bales in front of you.

Generally speaking, the differences aren’t going to be very big – but the next time your horse mysteriously starts losing weight, or losing muscle condition over his topline, you might want to question your hay supplier or get your hay tested.

For example – if your hay got rained on after it was cut, the rain can shatter the leaves, which is where much of the highly digestible protein is found in your hay.  And given how much of your horse’s daily diet is made up of hay, a small decrease in protein can have a big impact.  Let’s take a look at the math behind this:

A 1000 lb horse should eat 1.5-2.0% of its body weight per day in forage – that’s 15-20 lbs!

  • Hay A has 10% protein: 20 lbs of hay x 0.10 protein = 2 lbs of protein intake per day
  • Hay B has 8% protein: 20 lbs of hay x 0.08 protein = 1.6 lbs of protein intake per day

In this scenario, you’d have to feed an extra 5 lbs of Hay B per day to be feeding the same total protein as Hay A provides!

But how much difference does this really make, you ask? If your horse’s intake is already on the low end of protein requirements for his size and activity level, then a 2% drop in hay protein would potentially show up in 2 to 6 weeks. Over that time, all else being consistent, a decrease in general muscle tone, and muscling over the topline, will start to appear. Fortunately, it’s pretty easy to combat – in many cases, simply tossing in an extra flake or two of hay per day, or adding a ration balancer or 1 – 2 lbs of grain per day, at feeding time will combat the decreases – and what horse won’t love you for that?

Determining the Value of Rained-On Hay

George eating hay in his paddockRain occurring while cut hay is laying in the field causes both yield and quality losses that reduce the value of the crop as an animal feed and a marketable commodity.

Weather-induced losses are caused by:

  1. Prolonged plant respiration reducing soluble carbohydrates and overall energy content
  2. Leaching of soluble carbohydrates, protein, and certain minerals from the hay
  3. Leaf shattering and loss, removing the highly digestible and high protein portion of the forage
  4. Microbial activity metabolizing soluble carbohydrates and reducing energy content
  5. Color bleaching

How much does rainfall reduce dry matter yield?

Several researchers have studied the effects of rainfall on cut alfalfa. Wisconsin researchers measured dry matter losses of 22% when alfalfa was exposed to 1 inch of rain after 1 day of drying (curing). Similar hay dried without rain damage lost only 6.3% of the initial yield. Losses appear to be greatest after partial drying of the forage has occurred. In this same study, alfalfa exposed to 1.6 inches of rain over several days suffered a 44% loss in dry matter. Michigan researchers conducted several different studies to examine the effects of rainfall on field cured alfalfa. The first study reported maximum dry matter losses of 34%. In a second study, rainfall intensity was kept constant at about 0.7 inches but spread over periods of 1 to 7 hours. Dry matter losses ranged from 4 to 13%, with highest losses occurring when the rain was spread over a longer duration. Overall, dry matter losses were much lower in these experiments even though rainfall amounts were about 2 inches.

Other species have been studies as well. Yields losses of birdsfoot trefoil appear to be less than alfalfa, while red clover shows even less dry matter loss due to rain, and grasses suffer the least amount of dry matter losses. Dry matter losses are most crucial to the person responsible for baling the hay. Dry matter losses usually represent a significant decrease in income since less hay is available for baling, feeding, and selling.

How does rainfall reduce dry matter yield?

Three primary factors are involved in dry matter losses; leaching, respiration, and leaf loss. Leaching is the movement of cell solubles out of the plant. Components of the plant that are very water soluble are leached out of the forage and lost when rain occurs. Unfortunately, most of these compounds are those highly digested by the animal. They include such components as readily available carbohydrates and soluble nitrogen, minerals, and lipids. About one-half of the dry matter leached by rain is soluble carbohydrates.

Unlike other livestock, losses of soluble carbohydrate can be beneficial for some horses. Laminitis is a painful and debilitating disease of the horse hoof. Laminitis typically occurs during periods of increased or rapid intake of water soluble and nonstructural carbohydrates. In order to manage lamintic horses and reduced amounts of carbohydrates in harvested forage, horse owners have resorted to soaking hay. A number of research trials have confirmed removal of carbohydrates from hay by soaking in either 30 minutes of warm or 60 minutes in cold tap water. Soaking hay is a cumbersome, messy, and time consuming process. Purchasing rained-on hay with naturally low levels of carbohydrates is a possible alternative.

Respiration (breakdown of soluble carbohydrates by plant enzymes) occurs at nearly 2% dry matter per hour in fresh forage, and declines almost in proportion to the decrease in moisture content until the plant reaches approximately 60% moisture. Every time the forage is wetted by rain, respiration is either prolonged or begins again in cases where the cured forage was below 60% moisture. In either case, additional dry matter is lost.

There is some disagreement in the research literature regarding the amount of leaf loss that occurs in cut alfalfa as a direct result of rainfall. In Wisconsin studies, leaf loss ranged from 8 to greater than 20% as a percent of the initial forage dry matter when rainfall amounts were from 1 to 2.5 inches. In Michigan studies, direct leaf loss was much lower (0.5 to 4.2%). Perhaps the issue of leaf loss from rainfall is a mute point. Experience and common sense tell us that rain damaged alfalfa is more predisposed to leaf shatter after it dries, and rainfall often means additional raking and more lost leaves.

How does rainfall intensity and forage moisture affect losses?

Research is conclusive on these two points. Given the same amount of total rainfall, a low intensity rain will result in more leaching of soluble compounds than a high intensity rain. Also, as forage moisture content declines, it is more prone to dry matter loss from rain. In Wisconsin rainfall studies, the maximum loss in dry matter (54%) was a treatment where 2.5 inches of rain fell on hay that was nearly dried.

How does rainfall affect forage quality?

Perhaps nothing is more frustrating than to see excellent quality alfalfa turn into unsuitable feed with each passing rain and subsequent raking. Most rainfall studies are in agreement that wetting of field dried alfalfa has little impact on protein concentration. For rained-on hay, it is common to see relatively high protein values in comparison to fiber concentrations, unless significant leaf loss occurs. With the leaching of soluble carbohydrates, structural fibers (acid and neutral detergent fibers) comprise a greater percent of the forage dry matter. Depending on numerous factors, the digestibility of rained-on hay may decline from 6 to 40%. Changes in fiber components are thought to occur by indirect mechanisms, where the respiratory activity of microorganisms has a concentrating effect on fiber components by oxidizing carbohydrate components; additional fiber is not made during the wetting process.

Conclusion

Rained on hay can be a suitable forage, but quality depends on several factors. Forage quality tends to be retained if rain occurs soon after cutting when the forage has had minimal time to dry; the rainfall was a single event compared to a multiple day or drawn-out event; rainfall intensity was higher versus a longer, lower intensity event; and the forage has not been re-wetter numerous times. Rained on hay is actually beneficial for horses prone to laminitis and other metabolic disorders because of its reduced carbohydrate content. Analyzing forage for nutrient content is recommended, but can be especially useful when determining the quality of rained on hay.

This article is reprinted with permission from Dan Undersander, University of Wisconsin and Krishona Martinson, University of Minnesota. This and other horse nutrition articles can be found at http://www.extension.umn.edu/agriculture/horse/nutrition/.

Manage Pasture to Help Control Horse Feed Costs

Widgy in Grass_BRManaging pasture can be a very important tool in controlling feeding cost for all livestock, particularly horses being kept on small acreages.  If pasture is going to provide a substantial amount of the required nutrition for a horse, it takes about 2-3 acres per 1100 pound adult horse.

There are a number of key steps in managing pastures, particularly small acreages

  1. Do not turn the animals out on pasture too early in the spring.  Forages need some growth to recover from the winter and allow root systems to develop.
    1. Do not turn animals out on tall cool season grasses such as brome grass and orchard grass until the plants are 8-10 inches tall.
    2. If pastures are short cool season grasses such as Kentucky blue grass or rye grass, the plants should be 6-8 inches tall before grazing.
    3. If you do not know your pasture composition, err on the side of allowing adequate growth before grazing.
  2. Remove animals from the pasture when plants are grazed down to 3-4 inches in height.  Grazing too early or too long and allowing animals to eat the grass off too close to the ground will kill the grass and turn the pasture into a dirt lot where the only green plants are weeds, requiring expensive renovation.
  3. If you have limited acreage, consider purchasing some temporary fencing so that you can rotate the pasture.
    1. The outer fencing should be a safe, permanent fencing.
    2. You can cross fence the pastures with temporary fencing such as capped steel posts and appropriate electric wire.
    3. By allowing the animals to graze one section, then moving them to another section to allow the first section to recover, total pasture yield can be increased substantially, helping to control total feed costs.
    4. Clip and drag the pastures after you pull the animals off to control weeds and control parasites and flies.
  4. Make certain that fresh clean water is available at all times and that salt is available at all times.  If you are not feeding a balanced horse feed or ration balancer, offer appropriate mineral free choice as well.
  5. If space is very limited, keep a dry lot area where animals can be fed and watered to prevent areas of pasture from being overgrazed.
  6. Check with your local extension team for additional recommendations for your area and for recommendations on fertilizing pastures.  Dr. Krishona Martinson at the University of Minnesota, St. Paul, MN has published some excellent guidelines for pasture management.

A small investment in supplies to allow pasture to be managed and rotated can pay for itself in higher pasture yields.  Managing the pastures and selecting the right feeds can help manage total yearly costs as well as improve animal health and condition.

Spring Pasture Time for Horses!

Toby GrazingIntroducing horses to growing pasture is a welcome event each year, yet must be approached with caution. Introducing the horses to pasture too soon in the season or for too long a time period can be bad for both the pasture and the horses.

The following are some guidelines to consider:

  1. Do not turn the horses out on pastures too early. Grass needs time to recover from the stress of winter and should be allowed to re-grow to 6 to 8 inches in height, depending on the species, to allow roots to grow and to store some energy before being grazed.
  2. Horses should be fed hay before going out on pasture the first time. Do not turn them out with empty stomachs!
    1. Initial grazing should be limited to 15 to 20 minutes and gradually increased each day by 15 minutes until the horses are out for about 4 or 5 hours, at which time they can be allowed unrestricted time.
    2. If horses are allowed too much initial grazing time, the risk of digestive disturbance is increased as it takes the microflora in the gut some time to adjust to the difference in forage source.
  3. Do NOT overgraze! Pastures should not be grazed to below 3-4 inches in grass length or you will wind up with a dirt lot fairly quickly. Some weeds are also hardier than most grasses, so if pastures are over grazed, weeds will become more prevalent.
  4. Remember that cool season grasses growing very rapidly can be high in plant sugars (fructans), so caution is in order.
  5. Grazing muzzles might be an option for helping reduce rapid intake.

Proper introduction of horses back on pasture needs to be managed for the health of the horses and the health of the pastures!

Replacing Hay with Complete Horse Feed

A large boarding barn asked me to stop out and review their feed program as they were going to be making a change. The farm has over 100 horses in their care, and wanted to review the proposed change prior to placing their order.

They were currently feeding an economy pellet with an average feed rate of 6 pounds per horse per day. The new product the owner was considering is a mid range product that contains added fortification, as well as biotin and yeast culture. This would be a great enhancement to their current feed program, especially since their forage was not the best this year.

As I visited with the farm owner he explained that he was running dangerously low on his hay supply. He had priced hay from various sources, but the costs were excessive. He felt that if he transitioned the farm to a complete feed product, he could reduce his hay feeding rate by 50% per horse, and just use the complete feed.

He stated that even though the product was more expensive per ton than his current feed, but he would be saving money by feeding just the 6 pounds of complete feed per day. It was at that point that I realized he had not read the recommended feed rates for the product he was considering.

I agreed with the owner that complete feeds are an excellent choice to help balance a diet when forage is not readily available, or horses have a problem eating hay. I then went on to explain that he could reduce his hay feeding rate by 50% per horse per day, but he would need to compensate for the difference with additional complete feed beyond the 6 pound level of his traditional grain source.

Moral of the story: Complete feed products are great for horses with limited or no hay diets, but be sure you are following the recommended feed rates listed on the tag!

Stretching Your Horse Hay Supply

This article is courtesy of Krishona Martinson, PhD, University of Minnesota.

Most horse owners have noticed that the price of feed (both hay and grain) has increased.  At a hay auction in Sauke Center, MN, the 10-year average for horse quality hay (101-125 relative feed value) is $100 a ton; however, this year (2013), that same hay is averaging $220/ton.  There are several key factors that have contributed to these increases, including extreme weather patterns (i.e. drought), high oil prices, currency fluctuations, a struggling economy, and a market that makes growing corn and soybeans more profitable and less risky compared to hay.     

Horses have evolved on diets composed entirely of forage. Therefore, forage should be the primary component of a horse’s diet (at least 2/3 of their diet). Thus, horse owners, unlike other livestock owners, have few options other than forages to use to meet their horse’s nutritional requirements. 

However, there are management practices that can help horse owners ride out high feed prices:

  • Horse owners should take a critical look at equine body condition and maintain a body condition score of 5 (on a scale of 1 to 9).
  • Horses that maintain their weight on forage-only diets do not usually require any concentrate (grain).
  • A well-formulated ration balancer (concentrated vitamin and mineral mix) will ensure that vitamin and mineral needs are being met when dried hay is the sole dietary component.  Even the best, nutrient-dense hay will be deficient in essential vitamins and minerals, including vitamin E, copper, zinc, iodine, selenium and manganese (in alfalfa hay).

While all forage offered to horses should be free of dust, mold, weeds, and foreign debris, the nutrient density of the forage offered can vary depending on the type of horses being fed. Forage selection should be based on horse needs, as there is no one forage best suited for all classes of horses.

  • For example, providing nutrient dense forage like vegetative alfalfa hay to ‘easy keepers’ can create obesity issues; however, that same hay would be a good option for a performance horse with elevated nutrient requirements.
  • Have hay tested for quality to help determine how much and what type is best to feed to individual horses.
  • Keep in mind that higher quality hay usually demands a premium price and such hay is not needed by all groups of horses. 
  • Finally, older hay, if stored properly, is usually a great option for horses. 

Plan ahead and know how much hay you need. Horses eat roughly 2 to 2.5% of their body weight in feed (hay plus grain) each day.  For example, an average 1,000 pound horse will eat around 20 to 25 pounds of feed daily, plus water. Weighing the amount of feed offered will help to avoid over-feeding. 

When calculating hay needs, make sure to account for wasted hay. In a recent study conducted by the University of Minnesota, feeding round-bales to horses without a round-bale feeder resulted in 57% waste, while using different feeders ranged from 5 to 33% hay waste.  Although feeders do cost money, all round-bale feeders tested paid for themselves (due to reduced amounts of waste) in less than 10 months with hay valued at $200/ton.  A Texas study found that when horses were fed in a box stall, waste from feeding small square bales off the ground was 7% compared to only 1% waste when hay was fed in a feeder.  Using a feeder, regardless of bale-type, is essential to reducing waste and stretching your hay supply. 

Finally, have a good working relationship with a hay supplier to ensure a consistent and reliable source of hay.  Consider adding hay storage space to reduce the effects of price and seasonal fluctuations.  For example, hay is sometimes more expensive in the winter vs. the summer.  Buy hay early (do not wait for second or third cuttings) and budget for the price increase by re-evaluating how many horse you can afford to feed.