What Is Laminitis In Horses?
Laminitis in horses is inflammation of the soft parts of the hoof, with a laminar appearance. These “plates” join the horny part of the hoof with the third phalanx, which is the last bone in the horse’s foot.
Unfortunately, it is a frequent problem in all horses, although it has also been described in sheep, goats and pigs. However, in the case of these slender quadrupeds, it is the most serious and the most common in the veterinary clinic.
Laminitis in Horses: A Brief Approach to Hoof Anatomy
In a healthy animal, the third phalanx is attached to the inside of the horny part of the hoof by a suspender device. The inner surface of the hull folds into sheets to increase the grip space of this suspender device. In a horse with laminitis, these plates fail and the phalanx is not properly attached to the hoof.
The horse’s weight and your own movements will continue to push the foot bone towards the ground normally. However, without hoof protection, blood vessels rupture and soft tissue becomes inflamed. Therefore, acute pain and lameness do not take long to appear.
Onset and evolution of the disease
Laminitis begins when the cause triggers laminar separation, which can last between 30 and 40 hours. During this period, before symptoms appear in the extremities, the horse usually experiences problems:
- Gastrointestinal.
- Respiratory.
- Reproductive.
- Kidneys.
- Endocrine.
- Immunological.
These multisystemic alterations, anatomically distant from the hull, are due to the discomfort generated by the disorganization of the laminar anatomy. This is called the development phase and it doesn’t always happen. There are animals that go straight to the acute phase, without any apparent health problems having previously manifested themselves.
acute phase
As we have already said, the developmental phase ends up merging with the acute phase when the first signs of pain in the paws appear. It lasts from that time until there is clinical evidence of displacement of the phalanx within the hull.
A horse with acute laminitis tends to shift weight from one leg to the other. This behavior, no doubt, is performed in order to relieve pain. Even so, at some point, the animal is forced to support itself on the affected paw and the discomfort returns.
chronic phase
If the horse does not die during the acute phase, it will suffer phalanx displacement within the hoof. This is the hallmark of chronic laminitis and can be seen on an x-ray. Symptoms at this stage of the disease can last indefinitely, including:
- Mild but persistent lameness.
- Severe pain: the horse will want to lie down longer.
- Total degeneration of laminar attachments.
- Deformation of the hull wall.
- Penetration of the hull plant through the displaced bone.
How serious is laminitis in horses?
Laminitis is, without a doubt, the most serious disease that can occur in a horse’s foot. In fact, it is considered the second leading cause of mortality in horses, after colic. If death does not happen due to natural causes, it is customary to resort to euthanasia, due to the permanent suffering of the animal.
Final note: laminitis in horses and its relationship with the gastrointestinal tract
Most authors state that laminitis is a sequelae of a remote event, not related to the paw. This, at first glance, may seem strange. However, this disease has often been shown to directly involve the gastrointestinal tract. The causes were described as:
- Excessive consumption of grains and carbohydrates.
- Inflammation of the small intestine.
- Colic.
- Acute diarrhea.
However, there is a cause that arouses, in particular, the curiosity of many veterinarians. It is the alteration of insulin metabolism. It is said that horses with a history of insulin resistance tend to suffer from laminitis.
To test this hypothesis, experimental studies have been carried out with horses, monitoring some individuals with prolonged hyperinsulinemia. All ended up developing laminitis in less than 72 hours.
Therefore, it is recommended that horses undergo regular blood tests. Thus, if hyperinsulinemia is detected, techniques can be used to reduce its concentration in the blood and, above all, restore insulin sensitivity. For example, through low glycemic index diets for weight loss and moderate exercise.
