Recognizing and treating laminitis in horses: Causes, symptoms and stages

What is laminitis in horses?

Laminitis (pododermatitis aseptica diffusa), also known as laminitis, is an extremely painful disease that occurs in horses. Laminitis is defined as an aseptic inflammation of the hoof corium of the horse, in which the horn capsule of the hoof becomes detached from the underlying corium of the coffin bone, and if it is not treated early enough, the disease can take a dramatic course . Laminitis is a diffuse, aseptic inflammation that is not triggered by germs and is therefore not an infectious cause. It can affect all of the horse's hooves and can also affect any horse. Laminitis occurs more frequently on the front hooves. The triggers of laminitis are varied. Overweight horses are often affected, but metabolic imbalances are also a risk factor for laminitis. Acute laminitis can develop into chronic laminitis and lead to relapses. If laminitis is recognized and treated in good time, the chances of recovery can improve.

Stages of laminitis

Laminitis is characterized by five different stages of the disease in horses. Laminitis can develop gradually. From the initial stage to the final or chronic stage. We explain the signs of laminitis.

1. Prodromal laminitis
2. Subacute laminitis
3. Acute laminitis
4. Peracute laminitis
5. Chronic Laminitis

Prodromal laminitis

The prodomal phase, also known as the prodomal stage, defines the onset of the disease. At this point, the horse does not show any clinical signs, but the laminae – colloquially known as lamines – begins to change in the affected hooves. Even with X-ray examinations, laminitis cannot be detected at this time.

The subacute laminitis

Subacute laminitis is also known as a mild form of laminitis, offers few clinical clues and usually occurs when the relapse occurred three days ago. Rotation of the coffin bone is hardly noticeable in the subacute phase and the typical laminitis symptoms are short-lived. This phase of laminitis is characterized by frequent weight shifts in the horse, as well as lameness that is only discovered in tight turns. In contrast to the acute phase, the pulsation of the metatarsal artery is milder.

The acute laminitis

In the acute phase of laminitis, the symptoms become apparent, horses with acute laminitis change their posture, relieve the front parts of the hoof and start tripping. The movement in walk and trot also changes and is defined in four different intensities:

1. Degree: Calm, alternating lifting of the hooves; inconspicuous in the walk, stiff gait in the trot
2. Grade: one hoof can be lifted without any problems; willing but stiff step
3. Degree: the lifting of the hooves becomes painful for the horse, attempts are repelled by the horse; in motion, the horse runs reluctantly
4. Degree: Any movement is refused by the horse, walking is only possible under duress

Furthermore, the temperature in the horn capsule increases. During a hoof forceps genetic examination, which is used, among other things, to diagnose a hoof ulcer, the horse reacts with diffuse sensitivity to pressure, especially in the sole and wall area. Although X-ray examinations should always be carried out if laminitis is suspected, no decisive findings are to be expected in the acute phase. X-ray checks should be carried out after 24-48 hours and depending on the further course.

The perakute laminitis

If the laminitis is very advanced, the sole may break through and, in the worst case, the horn capsule may become detached. The hooves may feel cold shortly before the break-through as the blood vessels are squeezed.

The chronic laminitis

Chronic laminitis means that the disease progresses further or there is a rotation of the coffin bone. The horse does not necessarily have to go lame with chronic laminitis. This stage can last for days, weeks or months, but some horses are affected by it for the rest of their lives. Whether a horse has already been affected by a deer or is a victim of chronic deer can often be recognized by the following characteristics:

• Hooves have multiple, non-parallel horn rings
• Bulbous hoof formation/ one-sided arched toe
• Poor horn quality / bulging sole / white line widespread
• Trachtenfußung
  

Chronic laminitis is divided into three stages:

The early chronic stage

• Rotation of the coffin bone is clinically proven
• Process can take days to months

Chronic acute stage

• Clinical findings resemble acute laminitis
• Coffin bone is already rotated
• Coffin bone unstable & can penetrate sole

The chronic stable stage (chronic stable laminitis)

• Minor local findings, such as tenderness or increased pulsation, may still be present.
• Walking in a straight line without lameness
• Wall and sole horn grow
• Horses are ready for voluntary exercise

When laminitis is far advanced, the horse usually only lies down and behaves apathetically. The symptoms intensify, the soles may break through and shoes may be broken off. That is why the veterinarian should be called immediately if there is the slightest suspicion of laminitis. Once the disease has become chronic, it can be controlled with veterinary assistance, but it can no longer be cured.

Symptoms of laminitis in horses

How is laminitis recognized? The symptoms of laminitis usually manifest themselves in severe pain. Colic-like symptoms can also occur due to severe pain. Classic pain symptoms are

• High heart rate
• High respiratory rate (pumping breathing)
• Elevated body temperature
• Pain-killing exercise  

Typical movement of horses suffering from laminitis:
The severely inflamed part of the front toe is relieved and the rear hoof section and the heels are loaded. There are problems in turning and turning around. Possible symptoms are:

• Changed posture
• Fore limbs stand outside the centre of gravity/ hind limbs are pushed underneath
• Tripping (unloading the front hooves)
• Warm or hot hooves
• Movement/gait changes at walk and trot
• Stiff motion sequence
• Lameness
• Turning pain
• Heel-to-toe footing (relief of the front parts of the hoof)
• Increased pulsation of the main metatarsal arteries
• Crown swelling
• Pressure sensitivity in the sole and wall area
• Increased temperature of the horn capsule & at the crown margin

What happens in the hoof in the event of laminitis?

The hoof corium connects the coffin bone with the horn capsule. The horn capsule and hoof corium are connected by fine lamellae. In laminitis, these hoof structures are damaged due to inflammation or also mechanical pressure.

Due to the inflammation of the coffin bone carrier, the coffin bone loses its hold within the hoof capsule and changes the position of the coffin bone. The horn capsule of the hoof detaches from the coffin bone. This leads to coffin bone rotation and lowering of the coffin bone. Either the coffin bone rotates with the tip downwards or it sinks inside the hoof capsule towards the sole. The deep flexor tendon pulls the coffin bone further out of its anchorage and in the worst case the horse loses the hoof capsule. This is called "shoeing out". The coffin bone can also break through the sole as a result of strong rotation.

Due to the inflammatory process and the swelling of the hoof corium, the blood circulation in the hoof is also impaired. Untreated and as the disease progresses, this leads to circulatory problems and an undersupply of nutrients in the hoof. Swelling and oedema formation in the hoof leads to enormous pressure, as it cannot expand. Hoof structures can thus be permanently damaged.

Diagnosis of laminitis

If laminitis is suspected, the veterinarian should always be consulted immediately so that he or she can get an idea of the state of the disease.

This is done, among other things, by palpating the horse's leg, looking for signs of inflammation such as heat or increased pulsation. In addition, the pain is localised with the help of hoof tongs by palpating the hoof in small steps. The vet then looks at the horse's movement pattern, if possible.

After completion of the initial examination, it is essential to take an X-ray of the hoof. The focus here is primarily on the alignment of the coffin bone and the hoof wall. Ideally, the coffin bone and hoof wall are parallel to each other. If this parallelism is not given and a rotation of the coffin bone is recognizable, the diagnosis is consolidated. As the disease progresses, X-rays should be taken regularly in order to be able to detect changes in time so that treatment can be adjusted accordingly.

In order to be able to determine the extent of the disease more precisely, venography is recommended in special cases. A contrast agent is injected into the blood vessels in the hoof, which makes them visible on the X-ray. This procedure provides information about the presence and severity of the disease. In this case, it is advisable to repeat the process during the course of the disease, even within a few days, even during the current deer attack. In this way, an accurate prognosis can be made about the course of the disease, which helps to optimize the treatment plan. Nevertheless, it should be noted that venography is relatively time-consuming and costly and is not performed by all veterinarians. Instead, laminitis improvement is measured by the resolution of symptoms.

First aid for laminitis

If laminitis is suspected , there are some immediate measures that can be taken to help the affected four-legged friend!

1. Call the vet!

Laminitis is an absolute emergency! Only quick intervention can prevent (progressive) rotation or subsidence of the coffin bone. The faster a veterinarian is on site, the greater the chance of avoiding long-term consequences.

2. Cool the hoof

Cooling the hooves with ice water or cooling pads is the first immediate measure that should be taken. The cold not only relieves pain, but also inhibits inflammation.

3. No concentrated feed and enough water

Especially if the cause of the deer disease is still unclear, concentrate feed should be avoided to eliminate possible disease triggers. If the disease is indeed feed-related, further steps can be discussed with the veterinarian.

4. Absolute box rest

For deer patients, strict box rest applies during an acute deer attack, preferably on soft ground.

You can find more first aid tips when your horse is sick in our article: First aid for horses

Treatment and therapy of laminitis

How is laminitis treated? If laminitis is diagnosed during the examination, it is important to act as quickly as possible to prevent the coffin bone from turning or sinking. As soon as laminitis is suspected, the affected horse must be given absolute stall rest on as soft a surface as possible. This must be strictly adhered to, especially in the acute stage of laminitis. In addition, the affected hoof should be relieved by continuous cooling.

Which treatment is suitable must be clarified with the veterinarian individually for each horse and according to the diagnosis. The first step should be to identify the causes and eliminate them. This could be done, for example, by changing the feed or by changing the husbandry.

To provide immediate relief, the horse can be given analgesic, anti-inflammatory and circulation-promoting medications . However, pain-relieving medication in particular should be used with caution in order to prevent the horse from putting too much strain on the hoof, even though the disease is still in the acute stage. In order to further reduce the pressure in the hoof, a deer bandage can also help. This not only cushions the hoof, but also protects against infections.

In the case of chronic laminitis, a special rehealing shoe is recommended once the symptoms have subsided. A "laminitis shoe" is open at the front to relieve pressure on the front toe wall and has a recessed bar which ensures that the load is transferred to the frog and heels. Plastic irons or adhesive fittings are also suitable. In order to decide which type of hoof treatment makes the most sense, the previously taken x-rays should be consulted.
It is not uncommon for acute laminitis to end in a chronic disease. Accordingly, many therapeutic approaches are aimed at slowing down the progression of the disease. Nevertheless, there are approaches that offer the hope that chronic laminitis can eventually be cured by eliminating the causes and that the functionality of the hoof can be restored.

Causes of laminitis

What is the cause of laminitis? Laminitis can have several causes . Sometimes several factors occur at the same time. In order to treat the disease and prevent further outbreaks, it is important that the respective triggers are identified and prevented. In this chapter, we present the most common causes of laminitis.

Basically, it can be summarized that a horse gets laminitis if it consumes more sugar and/or starch than is necessary for its needs over a longer period of time. Starch cannot be broken down properly in the stomach and small intestine, so it enters the large intestine undigested. There are bacteria there that feed on carbohydrates and multiply disproportionately when there is an oversupply of carbohydrates. This produces lactic acid, which kills the bacteria in large quantities, triggering toxins called endotoxins. The lactic acid also damages the intestinal wall and gets into the horse's blood together with the endotoxins. In this way, the whole body is exposed to hyperacidity.

Feeding - "Feeding deer

What is fed for laminitis? One of the best-known causes of laminitis is feeding. It is a decisive factor for horses prone to laminitis, especially at the beginning of the grazing season. Fresh grass contains a lot of so-called fructans. Fructans are produced during photosynthesis and are carbohydrates or energy that the grass does not need for its own growth and therefore stores. The protein content of the grass is not relevant and has no negative effect on the horse if it is grazed slowly. Another feeding error is giving quickly digestible carbohydrates, such as grain, and not feeding enough roughage. There is also an obvious connection between feeding and a horse being overweight, which also promotes laminitis.
The following feed can trigger laminitis in excessive quantities:(fresh) grass, clover, fruit, bread and grain.

Laminitis due to (over)exertion or lack of exercise – "March and stable deer" in horses

Overexertion, in which the horse has to walk or stand on hard ground for a long time, can lead to what is known as marching deer. Incorrect fittings can have the same consequence. If a horse goes lame, it spares the affected leg. This can lead to an overload on the other side, which can also lead to laminitis under certain circumstances. The specific cause of the onset of the disease in these cases is an inhibited transport of blood. This problem occurs mainly with the front legs, as they carry more than half of the body weight. Too little exercise is just as harmful as too much: the so-called stable deer occurs when a horse gets too little exercise. The blood flow in the body becomes irregular in this case, since the hooves are not alternately loaded and relieved.

Laminitis due to stress in horses

Stress or other overexertion can also be a hormonal cause of laminitis. Examples of possible triggers are a different daily routine, socialization with new horses or traveling. During stress, adrenocorticotropic hormone (ACTH) is produced, which stimulates the stress hormone cortisol. Since cortisol regulates the body's carbohydrate balance, discrepancies can result in laminitis.

Laminitis due to mistakes in dealing with horses

There are some mistakes that are made when dealing with the horse that can lead to laminitis. Examples include riding on hard ground, incorrect hoof care and watering heated horses with cold water.

Laminitis as a consequence of childbirth – "obstetric deer" in horses

The birth of a foal can cause uterine inflammation. This happens when the afterbirth is not rejected at all or not completely. If remnants of the placenta remain in the womb, endotoxins get into the mare's blood and poison her. This leads to laminitis. Another trigger for obstetric deer is inflammation of the mucous membranes of the uterus.

Laminitis as a consequence of a disease in horses

Various diseases, such as lung disease or a viral disease of the respiratory organ, can be triggers for laminitis. It may also occur as a side effect of Lyme disease. Laminitis can also develop in addition to metabolic diseases such as diabetes, Equine Cushing's Syndrome (ECS) or Equine Metabolic Syndrome (EMS). In the latter, the disease occurs due to the fact that in many cases the horse is resistant to insulin and the blood vessels become narrowed. Something similar applies to Cushing's disease: the pituitary gland releases too many hormones, so that insulin resistance and thus laminitis are also at risk here.

Laminitis as a consequence of medication – "drug rehension" in horses

Treatment of some diseases requires cortisone-containing medication with glucocorticoids and/or long-term corticosteroids. If this drug treatment is carried out in large quantities, this can also be a possible cause of laminitis, as the intestines and liver are overloaded.

Laminitis due to poisoning "Poisoning deer" of the horse

Poisoning can occur if the horse ingests harmful feed or plants. These include molds and poisonous plants, but pesticides and herbicides can also be dangerous. Eating the aforementioned substances impairs the metabolism, which can lead to laminitis. Vaccinations and worming treatments should also not be underestimated. If the horse suffers from a heavy worm infestation, all worms suddenly die off when a worming treatment is administered. This results in symptoms of poisoning. It is important to differentiate here that it is not the worming treatment itself that causes laminitis, but the mass death of the worms. Detoxification can support the healing of laminitis in horses.

Anti- laminitis rules

How can I avoid laminitis?

The causes of laminitis are very diverse. It is therefore only logical that the disease can be prevented in different ways. In addition, there are the individual characteristics of the horse, for example its age and breed, but also the way it is kept, past or current illnesses and how it is used. It is also important to know that not all triggers can be eliminated by prevention; however, the risk of laminitis can be reduced by taking appropriate measures.
The following are general tips for preventing laminitis, which are then supplemented by specific tips on feeding.

General tips for handling and keeping

1. Avoid overweight / diet
2. Move horse regularly
3. No work on hard ground
4. In case of lameness: support healthy leg with laminitis bandage
5. Check paddocks, for example for poisonous plants
6. Regular, professional hoof care and shoeing
7. Take hygiene measures at birth
8. Ensure that the afterbirth is complete

General feeding tips

1. Change food (slowly)
2. Adjust the feed dosage for the horse
3. Fodder without impurities
4. Pay attention to sugar and starch concentration in the feed (especially in grass and grain!)
5. Use fructan-reduced grass seed for paddocks

Feed tips for marriage-prone horses

Can my horse with laminitis go out into the paddock? These and similar questions arise if your horse is already suffering from laminitis. You should then be especially careful with possible triggers and prevent a recurrence of the disease:

1. Avoid excess fructan
   The fructan content in grass depends on the time of day, weather, and temperature, among other factors.
   If the sun is shining, but it is cold overall and the ground may even be frozen, a lot of fructan is stored and thus absorbed by a grazing horse. For horses that are susceptible to deer, this combination should therefore be avoided. Also, an excessively dry soil and strong sunlight or heavy rain on extremely dry soil do not provide the optimal conditions.
2. Avoid freshly mown and eroded meadows
   Short blades of grass, such as those found after mowing, contain high amounts of fructan. Logically, however, the horse cannot eat as much grass as on an unmown pasture. Ideally, a well-kept meadow should be used, which is neither too high nor too low and has as much leaf content as possible.
   If you sow a meadow that you want to use as a paddock later, you can already use seeds there that are specially designated for this purpose.
3. Limit grazing time
   Regulate your horse's grazing time and make sure that he is in the paddock regularly and not for too long. When feeding, you should still provide him with enough roughage in the form of hay or roughage substitute products, for example. You should make sure that these foods are low in sugar and starch.
4. Use scuff brakes
   Feed intake on pasture can be reduced by feeding brakes. Especially for horses whose paddock is very extensive, this can be an alternative and allow sufficient time in the pasture.
5. Cutting hay late
   For horses that are prone to deer, late hay pruning is recommended in order to have as little fructan as possible in the hay. Since not every horse owner can influence the hay cut, the hay can alternatively be soaked in warm water for at least half an hour. This also reduces the fructan content, but also reduces the vitamins it contains.
6. Creating a feeding plan
   In order to keep track of the feed, and thus the sugar and starch that your horse eats, you should create a feeding plan. In it, you take into account both the times in the paddock and the additional roughage given during the grazing season.
   A blood count can answer the question of what nutrients your horse needs. It also provides information on how to avoid an excess of some substances.
   If a horse is put on a diet, weight loss should proceed slowly. Losing weight too quickly can again favor deer.
7. Additional lining
   If your horse is given additional food, you should also pay attention to a low sugar and starch content. That's why many mueslis and beet pulp, for example, are suitable as supplementary feed.

Chances of recovery from laminitis

Can laminitis be cured?

It cannot be said with certainty whether laminitis is curable or not . Healing and life expectancy depend on the horse and the stage of laminitis and is therefore not a direct death sentence. One point of reference is the rotation of the coffin bone: no change means that the horse can be ridden as it was before it became ill. If there is a rotation of up to seven degrees, the probability of healing is still high. If the rotation is even more advanced, the horse is unlikely to return to sport. However, this scale is not universally valid and can be different for different horses. The worst outcome is that the horse is euthanized.

In order to keep the chance of recovery as high as possible, early detection and proper treatment of acute laminitis is important. If this does not happen, chronic laminitis can occur after two to three days, which lasts several weeks and, in case of doubt, can affect the horse for life.

Does shoelessness mean the death of the horse?

As a rule, shoeing does not occur at all because the horse is healed beforehand or the pain is so bad that the horse is euthanized.
If shoeing does occur, it is not automatically a death sentence: a new horn is formed so that a new hoof capsule is formed. This process can take several months to a year.

My horse has laminitis, do I have to put it to sleep?

Again, no universal answer can be given because this decision depends on the severity of the laminitis and the associated pain for the horse. Early diagnosis is a crucial factor. Whether the horse needs to be euthanised or has a chance of recovery should be discussed with the veterinarian in charge.

When is laminitis cured?

If the laminitis severely damages the hoof with rotation or depression of the coffin bone, recovery takes an average of one year. This is true even if there is no longer any visual impairment.

Once laminitis, always laminitis?

Once a horse has been affected by laminitis, it has a tendency to become ill again for the rest of its life.

Basically, the danger of laminitis exists regardless of the season, the weather is decisive. The disease is associated with great pain for the horse, which is why attention should always be paid to feeding and husbandry, and possible preventive measures should be taken.

Exercise for horses with laminitis

How do I move a horse with laminitis? Should my horse with laminitis be moved?

There is no general recommendation regarding the keeping and exercise of a horse suffering from or susceptible to laminitis. The following is a list of options that may be useful, but ultimately depend on the individual case, the severity and the current stage of the laminitis and must be clarified by a vet.

Complete immobilisation in the box is rather unsuitable, as lack of movement promotes the disease. However, the horse should not be forced to move if it does not want to in its condition. If the horse wants to move, hard surfaces are unsuitable. Sensitive horses in particular prefer soft floors. The procurement of the floor is also to be considered for box and paddock. For rides or if a hard surface cannot be avoided, hoof shoes can be used or the hooves can be shod. It is important that the horse can continue to have contact with its peers in order to reduce stress factors. If, for example, the horse is exposed to stress in a herd because it is being chased, it should not be allowed to go to pasture until it has healed and should be kept in a paddock with visual contact to other horses.

When can I ride and exercise again after laminitis?

Before the horse is put back under the saddle, it should make a motivated impression in everyday life and be happy to move. Only then should a laminitis horse be ridden again. In addition, the opinion of the vet should definitely be sought. If the x-rays no longer show any injuries, the horse can be ridden again as usual.

It is better to wait a few weeks or months more and have a regenerated horse in return than to rush things and aggravate the disease again.