Picture this: a lush, green field with a horse peacefully grazing. This image is almost every horse owner’s ideal vision of their horse at his happiest. But danger can lurk for some horses if you look a little deeper.

Certain horses and ponies are prone to grass founder (laminitis), particularly in the spring when grasses are high in sugar. Most horse owners would rather prevent laminitis than deal with it after it happens, so the best course of action is to recognize the red flags—times to be more vigilant—and know what to do next.

High-Risk Horses

Horses most at risk for laminitis are those with equine metabolic syndrome (EMS) and Cushing’s disease (also called pituitary pars intermedia dysfunction, or PPID).

Horses and ponies with EMS often have telltale symptoms, including a tendency toward obesity, insulin resistance and recurrent laminitis. Abnormal fat deposits along the crest of the neck, tailhead and above the eyes are typical, even when the horse is at a normal weight. The condition most often occurs in ponies and other breeds that evolved under harsh conditions and tend to be easy keepers.

Horses with PPID may have symptoms similar to EMS, such as patchy fat deposits and insulin resistance, but PPID usually begins to appear in older horses (over age 15). They may also start to lose topline muscling and develop a thick haircoat that sheds out later than normal, or eventually not at all.

If you suspect your horse has either of these conditions, schedule a vet visit for blood tests that will help confirm a diagnosis. If your horse has a metabolic disease, consider it a huge warning flag that he is at high risk for pasture-associated laminitis.

The Carbohydrate Connection to Founder in Horses

Laminitis can be caused by grazing on pasture that is too high in non-structural carbohydrates (NSCs). These include fructan, sugar and starch. Structural carbohydrates are the fibrous parts of the cell wall that give the plant rigidity; these are digested differently from NSCs.

You may have heard that fructan is the singular evil element in grass that causes horses to founder. However, more recent research has shown that pasture-induced laminitis cannot be attributed solely to fructan. There is no fructan in warm-season grasses, yet horses can still founder on them. Since the same environmental conditions that create high fructan concentrations also increase sugar and starch levels, it’s best to just limit all NSCs.

Conditions that Spell Trouble

In order to prevent laminitis in high-risk horses, you’ll need to start thinking about weather and grass-growing conditions. When the sun is shining brightly but other conditions limit the growth of the plant, NSC concentration in pasture plants will increase.

Here is a list of the danger signs to look for:

Temperature

“If it’s below 40 degrees Fahrenheit, the enzymes that help the plant grow don’t function anymore,” says Kathryn Watts, an internationally respected consultant and researcher specializing in pasture grass and horses and ponies prone to laminitis. She is based in Colorado and maintains a website at safergrass.org. “However, photosynthesis [which creates sugar] happens as long as the sun is shining, provided that the plant is not frozen solid.”

Concentrations of NSCs can double or even triple if these conditions (sunny and below 40 degrees) continue for several weeks. Since this commonly happens during spring and fall in many parts of the country, these seasons are often associated with grass founder in horses.

TIP: A useful tool that you can find at any hardware store is a min-max thermometer. Put it on the back porch and check it every morning. If it’s been below 40 degrees that night, start paying careful attention to any high-risk horses. After a few nights below 40, any horse that’s had laminitis in the past or has the body type that says “founder waiting to happen” should probably be removed from pasture entirely and fed hay that’s tested for low sugar content (see “Testing Sugar Content,” below).

Lack of Fertilizer

“Another thing that can limit plant growth is lack of fertilizer—usually nitrogen,” says Watts. “The plant might have enough sugar, but if it doesn’t have enough nitrogen to put that sugar to work and grow, the sugar starts piling up. I use the analogy of an assembly line: If the plant does not have all of the elements it needs to grow, the line shuts down and the other raw materials pile up.”

Since a lack of nitrogen can limit grass growth, it’s important to have the right fertilization schedule for your region. “Approach your extension agent or fertilizer dealer and tell them you’re looking for a moderate fertility level, not maximum production,” Watts advises.

Drought

Drought is another form of stress that will result in sugars piling up within the plant. “For example, in Texas, founder season happens when it’s very sunny and very hot,” says Watts. Drought may also cause fructan in cool-season grasses to turn to sugar, increasing chances of metabolically driven laminitis.

Mature Grass

When managing pastures, it’s important to mow or top the grass before seed heads appear. “Sugars and starch are very concentrated in the developing seed heads,” says Watts. “Many horses selectively graze them off; it’s like horse candy.”

Weeds

Most pastures are filled with weeds that horses are more than happy to consume.

“Some of the weeds in your pasture have the potential to contain more sugar than the grass,” says Watts. “The ones that I have tested personally that are really high in NSCs include dandelion, plantain and thistle.”

You can treat pastures with an herbicide to kill broadleaf weeds such as dandelions, which are particularly palatable to horses. Often this is enough to decrease the incidence of founder.

A thick, healthy stand of grass is the best defense against invasion of weeds and clover. While proper fertilization can decrease sugar concentration per mouthful of grass, there may now be more sugar per acre. When grass is more plentiful in previously overgrazed pastures, you may need to start limiting intake with a muzzle or decreased time at pasture.

It’s important to note that weeds may grow around dry lots where horses and ponies are housed to keep them off pasture. If those weeds are within reach of desperate flapping lips of horses, the risk of founder is still there. You may very well save your horse from foundering just by running a weed-whacker around the dry lot.

“Safe” Grazing

Regardless of what season the calendar says it is, keep an eye out for dangerous grazing conditions all year long.

“The worst places for laminitis are those where the grass stays green all winter long, like in Great Britain and the Pacific Northwest,” says Watts. “Their grass doesn’t ever really die. When the temperature is below 40 degrees, any green grass creates a problem for high-risk horses, regardless of what month it is.

“Here in Colorado, by December the grass is completely brown,” she continues. “If the weather has been dry, the grass can still be high in sugars.” Sugars may be leached out eventually by rain and melting snow, except in the case of grasses with a waxy coating, such as fescue. Fescue is commonly found in Kentucky and the Southern states, so keep in mind that it may be holding on to sugar longer if you are planning to put your horse on it in the winter or during a summer drought.

“People assume that dead grass has no nutritional value if it’s brown,” adds Watts. “But sugar is not green. The chlorophyll and protein may be gone, but the sugar isn’t necessarily gone. Don’t assume that brown grass is safe.”

Testing Sugar Content

If you’re unsure about your grass or hay’s sugar content, the best thing to do is get it tested. “Grab a few handfuls of brown grass and send it to Equi-Analytical Laboratories [the equine division of Dairy One Cooperative Inc.] and have it analyzed,” says Watts. This is only accurate if the grass is completely dead. (If the grass is green, you would have to flash freeze it and send it overnight on dry ice, which is very expensive.) If it’s dead, you can treat it like hay.

Average grass hay is around 12 percent non-structural carbohydrates on a dry matter basis but can range up to 30 percent. For high-risk horses, grass or hay should be less than 11 percent. This varies by individual horse and how much exercise he’s getting. As you test more hay and compare how your horse does on each batch, you will learn what he can handle without gaining weight or getting sore feet. There is no “one size fits all” recipe.

If your high-risk horse has been pulled off pasture, it’s important to test your hay for sugar content. “Any kind of hay can be high or low in sugar,” says Watts. “It’s not about species; it’s about growing conditions.”

For a list of other National Forage Testing Association certified labs, visit www.foragetesting.org.

Managing the High-Risk Horse

If you have a high-risk horse with a cresty neck, one of the best things to keep an eye on is his neck. “When the sugars get high in the grass, you can palpate his neck and feel a difference,” says Watts. “I call it ‘the Neckometer.’ When you put him in the dry lot, within a couple of days you should feel his neck getting softer. If you do something wrong, his neck will get hard very quickly.”

If the weather is conducive to making high-sugar grass, horses with more mild risk factors may still be able to stay on pasture with a grazing muzzle on. “But if you put the grazing muzzle on and his neck is still getting bigger, then it’s time to put him in the dry lot and leave him there,” advises Watts. However, she emphasizes that the only way you can really assess your horse’s risk level is to get his insulin levels tested.

Early Signs of Laminitis

Another tool Watts recommends to carefully monitor high-risk horses is a daily brisk trot on firm footing. Since the metabolic form of laminitis comes on very slowly, it’s possible to look for these subtle signs and get ahead of the problem.

“If you have a horse that normally has a nice, big trot and suddenly he just shuffles along stiff-legged or refuses to trot at all, that’s the horse that you bring back to your dry lot,” says Watts. “Feel his feet to see if there’s excess heat or an obvious pulse. These horses will often respond to being withdrawn from pasture very quickly.”

Keep the horse off of pasture until weather conditions have changed completely in a way that will lower the concentration of sugar in the grass. For any case of acute laminitis, contact your vet immediately.

Since metabolic laminitis is a relatively new area of research, make sure your vet is up to date on the condition and knows how to treat it.

“Endocrinology is a veterinary specialty,” says Watts. “The same goes for farriers. The farrier you loved when your horse was healthy may not have the skills to help him once he’s foundered.”

Exercise is Key

Many of the horses that struggle with grass founder are not exercised at all, or only very lightly.

“Except for a few rare cases of very hard-to-control insulin resistance, if you exercise the horse hard enough (to a sweat) three times a week, you can fudge a lot more on the diet,” says Watts. “It’s about balancing the amount of exercise with the amount of NSCs in the diet.”

Horses that are prone to insulin resistance should not carry excess weight. Watts recommends horses be kept fit, even with a slight hint of ribs showing. But the horse should also carry good overall muscle tone from an active fitness program—whether it’s riding, driving or longeing.

If you have a high-risk metabolic horse and you want to maximize his grazing time, you’ll need to be prepared to carefully evaluate him and the weather conditions every day. At the first sign of foot soreness or the crest thickening/hardening, move him to a dry lot and feed him low-sugar hay, or soak his hay for a couple of hours in plenty of fresh water to remove excess sugars. When your horse and the grass conditions improve, he can go back out again. However, it may not be until the season is over. Be prepared for a time-consuming challenge.

Further Reading
◆ Treatment and Recovery of Founder in Horses
◆ Feed to Prevent Founder
◆ An Overview of Laminitis

This article about grass founder in horses originally appeared in the April 2013 issue of Horse Illustrated. Click here to subscribe!

The post Preventing Grass Founder appeared first on Horse Illustrated Magazine.

Plenty has been written about the prevention, causes, and treatment of founder, but less information is available on whether or not afflicted horses will “successfully” recover. The answer, despite the availability of clinical exams to guide prognosis, is not as straightforward as it may seem. Here, two leading experts in their fields, as well as the owner of two horses stricken with founder, weigh in.

Diet & Equine Metabolic Syndrome

Raul Bras, DVM, CJF, APF, a shareholder and practicing veterinarian at Rood & Riddle Equine Hospital in Wellington, Fla., has extensive experience treating horses experiencing laminitis and founder. He says that diet and its relationship to equine metabolic syndrome (EMS) is likely the most common contributing factor.

“A very high percentage of laminitis and foundering of horses is due to equine metabolic syndrome,” he explains. And changing the diet, once EMS has been identified as the cause, can be one factor that contributes to whether or not your horse will recover.

“If the owner is not willing to put the horse on a weight loss plan, there is nothing you can do to the foot that is going to fix it or stop it,” says Travis Burns, M.S., CJF, TE, EE, FWCF, and associate professor of practice and chief of farrier services at the Virginia-Maryland College of Veterinary Medicine in Blacksburg, Va.

Since it is very easy to slip back into old habits and patterns, you should continue to diligently manage your horse’s diet going forward after receiving such a diagnosis.

“You have to keep the horse at an appropriate body condition score and have his metabolic profile within normal limits, or you are just fighting an uphill battle,” Burns adds.

Identifying Problems Early

While most horse owners are vigilant about having their veterinarians out to administer yearly vaccinations and dental exams, fewer have diagnostic tests, such as annual X-rays and barn-side insulin testing completed. This is particularly important with horses and ponies that are genetically or otherwise predisposed, in order to seek out possible problems before they arise.

Regarding insulin testing, Bras initially likes to test as much as possible to achieve a baseline.

“You have four seasons of the year. If you [test] in the winter, spring, summer, and fall, you can see how [insulin levels] fluctuate,” he says. Once the baseline has been noted, your vet can monitor for increases to it on an annual basis and make changes to the horse’s diet well before he experiences laminitis or founder.

Knowing if your horse is predisposed to a condition such as EMS goes well beyond making dietary changes. It can also help guide you in avoiding over-supplementation and in the treatment of other medical conditions your horse may develop.

For example, in some instances treating with steroids can trigger the development of laminitis. Bras advises that rather than helping, both over-supplementation and over-medicating can make laminitis and founder more difficult to treat.

Using a Venogram

Venograms, a type of contrast radiograph study, play a critical role in assessment, as early identification is a top contributing factor as to whether or not your horse will make a successful recovery.

“It all comes down to blood supply,” says Bras. “That’s why I am a proponent of the venogram.”

He likens venograms to weather reports because they give you time to prepare and potentially even prevent problems before they arise. By knowing that the blood supply to the foot has been compromised before a problem has already presented itself, you can take a proactive rather than a reactive approach to certain elements (such as farrier and dietary modifications) of your management plan.

Corrective shoeing, for example, can work to counteract mechanical failure, while dietary changes can address weight and metabolic issues before problems occur.

Aggressive Treatment

Should your horse experience laminitis or founder, immediate, bold treatment can play a key contributing factor in whether or not your horse will recover. Bras advises avoiding a “wait and see” approach. Instead, he recommends assessing the damage and determining how much blood supply is present, and using that knowledge to make decisions as to how to proceed.

While it may seem logical to think that a horse who experiences a high degree of rotation will be unlikely to recover, Bras explains that this may not be the case.

“You might have a horse that has equine metabolic syndrome and has an acute foundering that doesn’t rotate much or another with a lot of rotation,” he says. “Even if you have a lot of rotation, if you have identified it right away, there’s a strong chance you can save a horse.” He emphasizes that each case is individual.

Emergency Treatment

Should a horse experience laminitis but rotation has not yet occurred, Bras recommends the application of the NANRIC Ultimate cuff shoe as long as the bone alignment matches the shoe.

“That shoe gives the horse 18 to 20 degrees heel elevation,” he says. “The heel elevation helps to optimize the blood supply to the hoof, thereby increasing the chances for a successful outcome.”

Because it doesn’t have to be glued or nailed on, any veterinarian, farrier, or owner (under veterinary supervision) can apply it simply by wrapping it on to secure it to the hoof.

Monitoring sole depth, degree of rotation, and the amount of blood supply during this process are all factors that will guide your veterinarian in directing treatment options, including making the call in extreme cases as to whether or not the deep digital flexor tendon (DDFT) should be severed to relieve tension and prevent rotation of the coffin bone.

Signs Indicating Outcome

According to Burns, marked improvement in the horse’s comfort, the return of vascular perfusion and growth of the horse’s foot—specifically in terms of sole depth—are all signs that your horse may make a recovery and return to his previous level of performance, or at least a modified version of it.

As a referral farrier making recommendations to help achieve successful outcomes for farriers in the field, Burns recognizes the need to work within principles rather than methods. Understanding that varying methods can all reach the same goal, he says that the first and foremost guiding principle he would like to achieve is recruiting the frog and sole into load-bearing.

This can be accomplished by any number of methods preferred by the horse owner’s farrier, including pads, heart-bar shoes and clogs, all aimed at meeting the needs of both the horse and the owner’s management situation. No matter the method, Burns likes to see a shoe that relieves tension on the laminae when the horse is moving even when he is turning.

Burns also recommends principles to realign the hoof capsule around the distal phalanx (P3 or coffin bone).

“If a horse can’t or won’t show growth, particularly under the tip of P3 or sole depth region, that is a bad sign,” he says.

As treatment progresses, Burns recommends lowering the heel to an appropriate palmar angle for the individual horse without causing increased tension on the DDFT, which results in increased tension on the laminae.

Finally, he advises dressing the hoof wall back to match the dorsal surface of the coffin bone. He says that if the bone stays healthy, you’ve got a much better prognosis for a return to athletic performance.

In the end, both Bras and Burns recommend the combined efforts of a veterinarian/farrier team.

“It’s not a good idea to think that your farrier can handle it on their own,” says Burns.

This article about treatment and recovery of founder appeared in the April 2023 issue of Horse Illustrated magazine. Click here to subscribe!

The post Treatment and Recovery of Founder in Horses appeared first on Horse Illustrated Magazine.

Don’t let the optimistic array of new research findings, therapeutic products, and expert opinions deter you from the basics of helping your horse avoid or survive the disease that has broken so many owners’ hearts.

What you have seen of this too-common disease has probably shocked you. You’ve watched owners soaking and bandaging and gingerly hand-walking their stiff-legged, laminitic horses. You’ve seen hooves crusted with growth rings, scarred by abscesses, and shod with pricey designer horseshoes or boots.

Every horse is at risk of laminitis. It’s a disease with different forms, multiple causes, varying severity, and an impact like no other. Some horses recover to gallop again, some spend months on stall rest, and others live with low-grade chronic lameness, helped by a special diet, conscientious hoof trimming and medication for the rest of their lives.

For advice, we turned to a respected source on the subject. The Animal Health Foundation (AHF) funds laminitis research all over the world. The charity’s founder, Donald Walsh, DVM, is optimistic about how horse owners can prevent and manage the disease.

What is Laminitis?

Most people think laminitis is a horse foot disease, but it is more than that. The AHF defines laminitis as the breakdown of the internal supporting structures (“laminae”) between the outer hoof wall and the coffin bone inside the hoof. This breakdown can also damage the delicate circulation in the horse’s foot and cause great pain.

Laminitis commonly affects horses’ feet when hormone production is disrupted, but it is also caused by retained placentas in mares after foaling, or when an injured horse bears weight excessively on its good foot. Body-wide inflammation, such as a complication after surgery, severe diarrhea, or diseases like Potomac horse fever are other pathways. Horses may also develop laminitis when exposed to stable bedding made from black walnut trees.

The most classic laminitis is direct carbohydrate overload, caused when a horse gorges on grain. He may not look sick, but his feet can be damaged by a situation that could have been prevented.

Laminitis research focuses on any one of these causes of the disease. Researchers look at aged horses at risk for the hormonal disease pituitary pars intermedia dysfunction (PPID, or Cushing’s disease), which alters pituitary hormones. They also research how efficiently horses regulate the hormone insulin, how they handle stress, or how seasonal or gender-related hormones affect them.

The most familiar form of laminitis is the sore-footed aftermath of grazing on rich spring grass. Many of these horses have what is called equine metabolic syndrome, rooted in insulin dysregulation, and frequently are overweight with obvious cresty necks or fatty areas around the tail base, sheath and shoulders.

Signs of Laminitis in Horses

Laminitic horses are usually lame in both front feet and sometimes in all four feet. Laminitic horses take shorter, more tentative steps than usual, and will toss their heads when turning at the end of a walkway. They may stand with their hind feet tucked forward under their bellies, and their front feet strutted out in front.

But laminitis caused by hormonal problems may have been sending you warning signals for months by gradually altering the shape of the horse’s feet. Hoof wall ridges are common, but the Animal Health Foundation suggests that it is farriers who see it first; they will remark that the sole is flattening out or bruised, and that the white line around the border of the sole is stretching and flecked with hemorrhage even if the horse isn’t noticeably lame.

The Mechanics of Laminitis

When the inner lamina tissue are damaged by laminitis, the bone partially detaches from the hoof wall. If you’ve ever torn one of your fingernails loose, you know how much damaged lamina hurt. Now imagine bearing your weight on that ripped nail: That’s how a horse feels when standing on laminitic hooves.

Sometimes the lamina are mildly damaged; other times the damage is focused on a portion of the foot. Commonly, the toe region is the worst affected. In severe cases, the bone becomes unstable inside the foot.

According to AHF, founder is the painful, crippling result of a foot’s bond damaged by laminitis. When a horse founders, the unstable coffin bone rotates or even sinks, putting pressure on the sole of the foot, sometimes even puncturing it.

Veterinarians take X-rays to evaluate the rotation factor, and also may take a venogram to get a picture of how badly the circulation is damaged.

What can you do to reduce your horse’s risk of laminitis or founder, and what makes a laminitis emergency? Click here to continue reading about treating laminitis.

This article originally appeared in the April 2019 issue of Horse Illustrated magazine. Click here to subscribe!

The post An Overview of Laminitis appeared first on Horse Illustrated Magazine.

We all love to see our horse enjoying a graze on delicious spring grass. But that pasture your horse eats with such gusto is not as benign as you might think—particularly for horses with metabolic disorders or genetic predispositions, although any horse of any breed can develop grass-related hoof issues at any time. In fact, some horses are better off avoiding the green stuff altogether. Learn how to manage your pasture and feed program to prevent founder or laminitis in your horse.

Mineral Balance

While grass contains most of the nutrients your horse needs for strong, healthy hooves, it doesn’t provide all those nutrients in the right balance or quantities. Calcium, magnesium, and sodium chloride are commonly deficient; selenium and iodine are frequently low as well.

Other vital minerals like zinc, copper, and manganese may also be present, but their levels in relationship to one another will affect how available they are to your horse. Minerals compete for absorption sites along your horse’s intestinal walls.

For example, if zinc levels are too high, they can block copper, a mineral that’s essential for maintaining the robust lamellar tissue your horse needs for his coffin bone to be properly supported within the hoof capsule. Iron is another competitive mineral that inhibits uptake of other minerals that are prevalent in grass.

Starch and Sugar Levels

Sugars and starches can be present in pasture grasses in levels that trigger a laminitic event. These nutrients are meant to be digested in the small intestine, but if your horse ingests these simple carbs in quantities greater than the small intestine can handle, the excess will continue along the digestive tract into the large intestine.

The large intestine is populated with microbes that process digestible fiber. These beneficial microbes thrive in an environment with a relatively neutral pH. If they are overrun with

sugar and starch, their home becomes so acidic they can’t survive. When they die, they release substances that are toxic to your horse.

At the same time, acid-loving microbes take over and compromise the integrity of the intestinal wall, allowing those toxins to penetrate and enter your horse’s bloodstream. When they reach the hooves, they cause the blood vessels to constrict, starving your horse’s hooves of nutrients and setting off a laminitic event.

Forage with a simple sugar (technically known as ethanol-soluble carbohydrates, or ESC) plus starch level of 10 percent or less should be low enough to keep your horse’s microbial population happy. If the levels in the grass are higher and your horse shows signs of inflammation, you will need to limit or restrict your horse’s access to pasture (find grazing muzzle options here).

Some signs that your horse may be getting too much starch and sugar from pasture include a thick, cresty neck; tender feet; a distended or more intense digital artery pulse (on your horse’s ankle); flared or ridged hoof walls; and unusual weight gain or loss.

Instead of grazing, provide low sugar/starch hay 24/7 in a slow feeder, such as a hay net with small holes or another device. To learn what the sugar and starch levels in your pasture are, have it analyzed by an agricultural lab. The report will give you the information you need to determine if your pasture is safe. If you aren’t sure how to interpret the results, an equine nutritionist can decipher the data and help you balance your horse’s diet accordingly.

Mycotoxins

If your hay’s starch and sugar levels are low and your horse’s diet is balanced, but the grass is still triggering laminitis, mycotoxins could be to blame. Mycotoxins are naturally occurring toxic compounds released by fungi that live in grass. Mycotoxins are vasoconstrictors that are absorbed quickly through the small intestine and trigger a systemic inflammatory response, which can then cause laminitis.

According to Jennifer Duringer, Ph.D., director of Oregon State University’s Endophyte Lab, there are more than 500 known mycotoxins.

“Mycotoxin levels rise and fall seasonally and are present in more grass species than was once believed,” she says. “We are currently conducting a study to identify which species are infected.”

You can combat mycotoxins by turning your horse out on a dry lot instead of a pasture, although mycotoxins can be and often are present in cured hay. If you suspect your horse is suffering from mycotoxin-induced laminitis, try removing the offending toxins with a mycotoxin binder to reduce inflammation. These can be found in certain equine feed supplements that generally contain yeast derivatives.

Keeping a laminitis or founder-prone horse on pasture can be challenging, if not impossible. Keep up the good fight against pain and discomfort by reducing grazing as needed, testing hay, and being aware of potential mycotoxins.

This article about how to feed to prevent founder appeared in the March 2022 issue of Horse Illustrated magazine. Click here to subscribe!

The post Feed to Prevent Founder appeared first on Horse Illustrated Magazine.