Stomach, liver & intestines

Stress affects horses! It can be caused by high performance requirements, changes in feed, transport, weaning of foals, hierarchy conflicts, operations, illnesses and prolonged therapy with painkillers or medication and many other influences and events.

Susceptibility to colic, refusal to eat or stress-related strain on the gastrointestinal tract, inflammation of the gastric mucosa and stomach ulcers can be the consequences.

Inflammation of the stomach lining (gastritis) in horses:

Gastritis in horses occurs when the protective lining inside the stomach becomes irritated or inflamed. This can result from, among other things:

  1. Inappropriate feeding : Irregular feeding or too long a gap between meals can irritate the stomach. Horses are naturally adapted to continuously consuming small amounts of (low-energy) feed.

  2. Stress: Stressful situations such as transport, training, feed changes, illness or stable changes can affect the stomach. Stress hormones can increase the production of stomach acid and weaken the protective layer of the stomach lining.

  3. Medications: The use of certain medications, especially nonsteroidal anti-inflammatory drugs (NSAIDs), can damage the stomach lining.

  4. Intense training: Hard training, especially if the horse is exposed to an empty stomach, can irritate the stomach lining as increased stomach acid is produced.

  5. Colic (and other diseases): During the course of colic (or disease) and its treatment, severe pain (stress), prolonged food deprivation and the administration of various medications occur, which can lead to the development of stomach ulcers.

Stomach ulcers in horses:

Equine gastric ulcer syndrome (EGUS) affects various categories of horses worldwide. This syndrome is now divided into two distinct diseases based on the presence of lesions on either the squamous mucosa (Equine Squamous Gastric Disease, ESGD) or the glandular mucosa (Equine Glandular Gastric Disease, EGGD).

Peptic ulcers are deep sores or lesions in the lining of the stomach. Stomach ulcers can often occur as a possible result of persistent inflammation of the stomach lining. The exact relationship between stomach ulcers and gastritis is complex, but it is thought that long-term inflammation can weaken the protective mechanisms of the stomach lining, increasing the risk of ulcers.

If the stomach lining is irritated or inflamed for a long time, this can cause the protective mucous layer that normally protects the stomach wall from the aggressive stomach acid to become thinner. This makes the stomach wall more susceptible to damage from stomach acid. This can eventually lead to the formation of ulcers, which are open sores or lesions in the stomach lining.

It is important to note that not all stomach lining infections necessarily lead to stomach ulcers. Some horses may have gastritis without developing ulcers. Others may be more prone to developing ulcers, especially if they are exposed to chronic stress, regularly take certain medications, or their feeding habits are disturbed.

The exact cause and development of stomach ulcers is complex and can vary from horse to horse.

Therefore, if gastritis or ulcers are suspected, it is important to consult a veterinarian for an accurate diagnosis and appropriate treatment.

How do I recognize stomach ulcers in horses?

The most common symptoms of stomach ulcers are:

  • Recurrent colic
  • Poor/picky eating behavior
  • “Dunking” the roughage in water
  • Refusal to eat feed after giving concentrated feed
  • Apathetic behavior or increased restlessness
  • Loss of performance
  • Poor general condition
  • weight loss
  • Chewing or grinding teeth
  • Frequent wheezing or yawning
  • Copping
  • Belching
  • Mouth breath
  • Compulsion to saddle, hypersensitivity when grooming on the stomach
  • Hitting the rider's leg/spurs
  • Stubbornness / unwillingness to ride

Stomach ulcers are divided into four levels of severity using the “ulcer score”:

    Grade 0 (No Lesions): In this stage, the stomach lining shows no signs of lesions or damage. The mucous membrane is intact and shows no changes.

    Grade 1 (erosions): Small, shallow erosions or damage to the stomach lining occur here. These can be visible as superficial redness or slight changes in the mucous membrane.

    Grade 2 (ulcers): In this stage, deep ulcers can be seen in the stomach lining. Ulcers are deepened wounds or lesions that penetrate the protective layer of the mucous membrane. They can be painful and lead to inflammation.

    Grade 3 (Perforation): This is the most serious stage that involves perforation of the stomach lining. This means that the ulcers are so deep that they penetrate the stomach wall and expose the underlying tissue. This is a serious complication that requires emergency medical treatment.

      The ulcer score method helps veterinarians assess the severity of gastric ulcers in horses to determine the appropriate treatment strategy. Diagnosis and evaluation of stomach ulcers is usually done using endoscopy, which involves inserting a camera into the stomach to look directly at the lining. The information from the ulcer score can help veterinarians plan the optimal therapy for the affected horse.

      According to studies, up to 90 percent of sport horses and up to 60 percent of leisure horses suffer from stomach ulcers. These are alarming figures that show how important it is to pay attention to the signs of stomach problems and to act in time.


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