Laminitis is a painful and prevalent condition that can be deadly for horses. Two interlinked layers make up the hoof wall; the horn (outer insensitive layer) and laminae (underlying sensitive inner layer). In Laminitis, the blood flow to the laminae is affected. This decreased blood flow deprives its cells of nutrient-rich blood and oxygen, which results in swelling and inflammation of the hoof, causing excruciating pain for the horse. The treatment needs to be started immediately on the first sign of the deterioration to give the horse a fighting chance.
Laminae support the pedal bone of the hoof and help maintain the weight of the horse. There are different degrees of severances in Laminitis. In some cases, the pedal bone sinks too far it can be seen to protrude from the sole. It is irreversible in many cases and requires a lot of money, patience, and time.
To know more about different health problems in senior horses, check this article “Senior Horse Health Problems – Potential Risks, Symptoms, Causes, and Treatment“.
Causes of Laminitis in horses
Since laminae are sensitive to a wide variety of systematic diseases, therefore, several factors can cause Laminitis. Some of them are mentioned below:
Diseases with inflammation
Diseases which cause inflammation can flare up Laminitis, such as:
- certain types of colic
- retained placenta
- severe pneumonia
Equine Cushing disease
A disorder in the pituitary gland, which is present on the base of the horse brain, causes hormonal imbalance. This hormonal imbalance leads to various clinical situations such as long, wavy hair coat, excessive thirst, appetite, and abnormal sweating. Without proper treatment, the condition worsens and becomes a cause of Laminitis in many horses.
Equine Metabolic Syndrome (EMS)
EMS is a metabolic disorder in which horses require a lower plane of nutrition to maintain body weight, unlike other horses. Laminitis is a devastating feature of EMS. Although there may be many causes of Laminitis, the most common cause is a disease called grass founder. Grass founder occurs in horses and ponies on pastures.
Mechanical overload is a slightly less common cause of Laminitis. Excessive weight-bearing exercises can cause profuse blood flow in the foot leading to Laminitis.
Excessive intake of soluble carbohydrates
If the horse intakes a large number of carbohydrates, it is unable to digest it. Hence the undigested carbohydrates are pushed to the hindgut.
As soon as the undigested food enters the hindgut, it causes a series of reactions, which ends up releasing toxins in the bloodstream of the horse. These toxins provoke a response within the horse that is thought to disrupt blood flow in the feet, which can cause Laminitis.
A dramatic change in the environment, excessive traveling, and exertion of the horse can cause Laminitis. Mares are more vulnerable to Laminitis after foaling because of additional physical stress.
Many horse owners overfeed their horses. When a horse is receiving more calories than it can burn off, it gains weight. Obesity can be very detrimental to the health of the horse. It causes increased strain on the horse’s vital organs as well as its limbs. Hence, all horse owners need to remember that the native breeds can live on average pasture. Horses can very quickly become overweight if allowed to graze fertilized cattle pasture.
Feeding a Horse with Laminitis
Feeding a horse with a history of Laminitis needs to be done very carefully and with great consideration. It is often a time consuming and frustrating job. However, if not done properly, it can result in dire consequences for the horse. Here are some feeding methods:
Base the diet on low sugar pasture or hay
As mentioned earlier, one of the leading causes of Laminitis is indigestion. Horses are unable to digest a large intake of carbohydrates. There are two ways to avoid feeding your horse with high sugar content.
- Prevent your horse from overgrazing, such as take your horse grazing in the early morning when the sugar content in the pastures is lowest.
- Feed your horse low sugar hays.
Feed according to your horses need to gain, hold or lose weight
Monitor the horse’s diets carefully. Make a scheduled diet plan for your horse, call feed helpline, or visit a vet while planning it. Follow the diet plan, meticulously. For example, if you believe that your horse is at its optimal weight, then its diet should be to up to 2.5% of its body weight. The feeding for horses with Laminitis should be low sugar forage (12.5 kg for a 500 kg horse) per day. All horse owners should remember to feed their horses according to the workload and type. In contrast, ponies and horses should be given around 1.25-1.5 percent of their body weight in food, including any grass and hay intake.
Never feed a grain-based feed to horses with Laminitis
If your horse is underweight and needs extra feed in addition to the low sugar feed, you must select its forage very carefully. Selecting proper feed for horses with Laminitis is very important. You should never choose a feed which contains the following ingredients:
- Oats, corn, wheat, rice, barley
- Millrun, mill mix, bran (rice or wheat), pollard
- Any form of steam flaked, micronized, or extruded grain.
Feeding little but often
This is the essential rule of feeding your horse. This imitates the natural food pattern of a horse. By doing this, the horse’s digestive system works on the track. It also satisfies the horse’s need to chew incessantly and prevents boredom.
Types of Laminitis
There are three types of Laminitis, according to Dr. Andrew van Eps, BVSc, Ph.D., associate professor of equine musculoskeletal research at the University of Pennsylvania, School of Veterinary Medicine’s New Bolton Center.
Endocrinopathies laminitis, which is associated with endocrine dysfunction and increased blood insulin
Supporting-limb Laminitis, which develops in the contralateral limb of horses with a painful limb condition
Sepsis-associated Laminitis, which occurs secondary to systemic inflammatory disease.
Signs and Symptoms of Laminitis
Acute laminitis symptoms in horses are very severe and sudden.
- The horse will become lethargic and show an inability or reluctance to walk or get up.
- Its trot will be visibly lame, especially when moving in a circle or on a hard surface.
- Since Laminitis is more common in front feet, the horse will favor its hind feet while standing.
- The horse will have pain in front point of frog; when walking, the horse might place its heels down first rather than its toes.
- The horse would feel the heat in the feet.
- A “sawhorse stance,” the forefeet extended out in front to relieve tension on the toes; the hind feet placed under them to carry the weight which their front feet cannot.
If the horse’s foot fails mechanically, it means that the Laminitis has progressed into the chronic phase. The symptoms of this phase are ongoing, and this is usually common in those horses that have a relapse from previous attacks. The following are the chronic symptoms.
- Wall deformities
- Draining tracts
- As with the acute phase, there can be varying degrees of lameness. It may become evident over time that the hoof is deforming, there will be an appearance of growth rings around the hoof wall. These symptoms generally indicate that the horse has suffered from Laminitis in the past. However, these should not be confused with hoof rings, which are due to changes in nutrition or due to stress.
- The heel will often become immovable than the toe
- The white line in the hoof will have widened.
- There might be a large crest running around the neckline of the horse.
- Stone bruises (bruised soles)
Treatment of Laminitis
Laminitis is one of the most studied and researched equine diseases. However, there is still not much known about it. Recognizing Laminitis early, regardless of its cause, is key to managing it successfully. Some new treatments of Laminitis have come up as a result of extensive research and studies.
- If any of the above symptoms are seen in your horse, it is pertinent to call the vet immediately. Precise treatment by a professional need to be administered as quickly and efficiently as possible, to prevent any long-lasting deformities.
- New treatment includes that the vet may advise x-rays of the feet, to show how much (if any) rotation has occurred. A farrier may also need to attend, under vet supervision, to correct the rotation and make sure the feet are in the best condition to facilitate recovery.
- It is advisable to move the horse to a smaller pen and bed the area down with a deep bed of shavings. The bedding needs to be able to mound into the hoof and around the frog to provide support.
- Remove any feed, including molasses licks.
- Provide the horse with fresh, clean water. If the horse is obese, it is essential not to starve it. Ask the vet to provide a nutritional diet.
- To minimize stress, ensure that the horse has a companion nearby. Environmental factors contribute to stress, so make sure that the horses are not jostled around and feel secure in their environment.
- Horse owners should not hose the horse suffering from Laminitis with cold water. They should not take them to a stream, even though the horses might feel comfortable initially. Still, prolonged exposure to cold can worsen the condition.
- Make the horse customized shoe for the deformed feet; to provide support to the sole.
- Treating Laminitis with mineral oil. Oil is poured into the horse’s digestive tract through a nasogastric tube. This helps indigestion.
- Other treatments of Laminitis include giving fluids to the horse if it is ill or dehydrated.
Prevention of Laminitis
It has been mentioned above time, and again, the treatment of Laminitis is a time consuming expensive and painful process. So prevention is better than cure. Here are some ways horse owners can prevent Laminitis:
- To avoid overgrazing and consequent ingestion, restrict grass intake by using electric tape to strip graze. Grass contains a large percentage of soluble carbohydrates (fructans); excess consumption can lead to Laminitis, especially in spring and autumn.
- Similarly, to reduce the amount of fructan intake, let the horse graze the grass at night rather than at day time. As there are fewer fructans in the grass at night.
- For this same reason, try not to let your horse feed on the frosted or lush grass. Ask the landlord to decrease clover and sugary ryegrasses in the turf, allow more organic herbs and grasses to grow.
- To lower the stress on horses and especially ponies, categorize them into groups based on which ponies need the same level of management. This will keep them busy and allow them to carry normal behavior and make them feel safe.
- Maintain a good exercise programmer to prevent obesity.
- Monitor the gait of horses vigilantly and ensure that a farrier inspects their feet every four to five weeks. This will not only ensure that the foot is in prime condition, but will also make diagnosing Laminitis easier and faster.
- Check the chest of the horse frequently. If it feels hard, immediately remove the horse from the grass until it softens.
Essential supplements for Laminitis
Research has shown that certain key ingredients can be used to combat the components that are the main cause of Laminitis.
Essential fatty acids
Essential fatty acids, such as omega-three fatty acids, can disrupt the cascade of negative effects leading to Laminitis after starch, fructan, and sugar overload. Omega fatty acid has anti-inflammatory properties and can, therefore, help the horse even after it has Laminitis.
It is an antioxidant and can help reduce oxidative stress, which causes Laminitis.
Chromium and Magnesium
These help to metabolize insulin and sugar. Therefore, taking it can prevent the horse from developing Laminitis due to Insulin resistance.
Finally, because healthy hoof regrowth is important, hoof supplements that contain methionine, biotin, and other amino acids, plus zinc and other minerals, may be recommended.
Prescription Medications regarding Laminitis
These are non-steroidal and anti-inflammatory drugs, like Bute (phenylbutazone). They help relieve the pain and swelling of the horse.
Banamine® (flunixin meglumine)
They fight the endotoxins caused by colic or diarrhea.
If Laminitis is caused by bacterial infection or sepsis, antibiotics are administered.
Acepromazine or Isoxsuprine
Medications such as these can dilate the blood vessels, due to which the flow of blood to the foot having laminitis increases. It helps to nourish the laminae cells. It also encourages better blood flow to the foot.
Horses that get Laminitis because of Cushing’s should receive a daily dose of Pascend (the FDA-approved version of pergolide) to manage the underlying condition.
Levothyroxine is being tested as a medication for the Insulin Resistance seen in Equine Metabolic Syndrome. It may be a valuable prescription medicine in the battle against Laminitis.
Can Laminitis in horses be cured?
According to Dr. van Eps, equine veterinarians are more adequately equipped to arbitrate any experiments regarding the cure for Laminitis. This is because they’re more informed of the mechanisms required in each type of Laminitis. Research groups throughout the world have been trying to make a leeway of solving this disease.
The New Bolton Center team-which consists of Dr. van Eps; senior research investigator Hannah Galantino-Homer, VMD, Ph.D.; and associate pathology professor Julie Engines, VMD-is actively researching laminitis pathophysiology. This team is the perfect mixture of diligent, hardworking, and knowledgeable individuals. Therefore, their collaboration has accelerated the rate of discovery of the cure.
Dr. van Eps says researchers are close to identifying why Laminitis occurs. Secondary to endocrine disorders that lead to increased blood insulin-conditions such as Cushing’s disease, pituitary pars intermedia dysfunction, and equine metabolic syndrome. They state that some horses and ponies naturally produce a high concentration of insulin in response to ingested carbohydrates. If they identify why the high concentration of blood insulin interferes with the laminar tissue of the foot, they can understand how the disease is created, and only then can they look for solutions to block the interference.
For this approach to be successful, they need to address the underlying endocrine issue. Dr. van Eps believes that they can even reverse Laminitis if diagnosed in early stages, and the underlying endocrine disease is controlled.
Dr. van Eps is also confident about being able to intervene and prevent supporting-limb Laminitis in clinical cases effectively. He believes that the preventive strategies are more feasible now than they were before, as, in the previous years, they have reached new benchmarks. Now they can comprehend the minute details of the disease better. They believe that supporting-limb Laminitis is a blood perfusion problem that is associated with the load. Particularly, the lack of normal limb load cycling patterns seems to be the problem.
Researchers are discovering that when horses preferentially lean heavily on a limb, it directly disrupts blood flow to the hoof. To properly perfuse the lamellar tissue in the hoof, the horse must cycle weight on and off the limb. When a horse settles a lot of weight on a limb, it appears that they need to exercise that leg even more regularly than average. Clinicians can help with that.
To know more about different health problems in horses, check this article “Health Problems in Horses – The Most Comprehensive Account of the Major Health Issues in Horses“.