Gastric ulcer disease in horses is not one diagnosis with one universal protocol. The umbrella term equine gastric ulcer syndrome includes at least two different conditions, defined by the location of the lesions: equine squamous gastric disease, affecting the upper nonglandular region, and equine glandular gastric disease, affecting the acid-producing region normally protected by mucus and other defensive mechanisms. Both can occur in one horse, but evidence of one does not establish the other. Risk factors, treatment responses and prevention plans also differ.
An expensive mistake begins when general signs such as reduced appetite, declining performance or discomfort during girthing become a diagnosis without gastroscopy. These signs can accompany gastric disease, but also dental problems, musculoskeletal pain, subtle lameness, respiratory illness or intestinal disturbance. Responsible management starts with an accurate history, clinical examination and assessment of feeding and training, followed by gastroscopy when the veterinarian considers it appropriate. The aim is to identify the problem and change the forces that allow it to return. Record what the horse actually does and when, rather than interpreting every behaviour through a presumed ulcer diagnosis. Improvement after a treatment trial cannot establish which region was affected or prove that a lesion has healed. Individual treatment decisions, preparation for gastroscopy and changes to prescribed medication require the attending veterinarian. A management record helps that professional interpret the case; it is not a remote diagnostic tool.
One umbrella term, two different gastric conditions
The horse’s stomach is relatively small within its digestive system and secretes acid continuously, including between meals. A clear boundary, the margo plicatus, separates the upper squamous mucosa from the lower glandular mucosa. The squamous region does not have the same protection against acid and is vulnerable when acidic contents reach it, particularly during fasting and physical work.
Fast movement increases abdominal pressure and can drive acidic contents towards the squamous region. Exercising on an empty stomach reduces the fibrous layer that helps limit this exposure. Squamous disease therefore has strong management associations: long gaps without forage, large starch-rich concentrate meals, intensive training, repeated transport and confinement that restricts natural feeding behaviour.
Glandular disease is more complex. This mucosa normally encounters acid but protects itself through mucus, bicarbonate, blood supply and cellular integrity. Lesions develop when those defences fail, and their appearance and location vary. Current evidence does not justify explaining the condition solely as excessive acid. Workload, behaviour, inflammation and particular management patterns remain subjects of investigation.
Distinguishing the two conditions changes decisions. Squamous disease may respond relatively promptly when acid is controlled and risk factors are removed. Glandular disease can be less predictable and may require a different veterinary plan based on appearance, location and history. Using the general term EGUS without identifying the affected region is like describing limb pain without identifying the joint or tendon involved.
Not every minor change should be equated with a deep ulcer. Gastroscopy documents erosion, redness, bleeding, lesion severity and location, but clinical context determines their significance. Lesions may occur in a horse without obvious performance decline, while another horse’s poor performance may have a different cause despite incidental gastric changes. Observation and proof of causation are separate matters.
Signs: why appetite and behaviour cannot establish the diagnosis
Reported signs include slower eating, leaving concentrate feed, loss of body condition, altered temperament, yawning, tooth grinding, flank sensitivity, poor performance and recurring mild colic. Most are nonspecific. Feed refusal may reflect dental pain, fever or travel fatigue; reluctance to move forward may arise from back or foot pain.
Sport horses are particularly vulnerable to selective interpretation. When times deteriorate or a horse stops responding, the team may choose one convenient explanation. Performance involves cardiovascular and respiratory function, muscles, joints, feet, nerves, nutrition, behaviour and the rider or driver. A new behaviour warrants examination rather than an immediate assumption that one medication will resolve everything.
Girth sensitivity is a familiar example. It may be associated with gastric discomfort, but an unsuitable saddle, chest or back pain, learned behaviour and environmental stress are also possibilities. The observation becomes more informative within a coherent pattern of feeding changes, weight loss, recurrent discomfort and a high-risk management programme. It remains a hypothesis requiring investigation.
Establish an individual baseline: meal-finishing time, uneaten feed, measured or tape-estimated weight, body condition, manure characteristics, behaviour during preparation, post-exercise heart rate and recovery time. A brief weekly record can reveal change before it becomes a crisis and reduces reliance on memories influenced by the latest competition result.
Severe or persistent colic, marked refusal to eat, rapid deterioration, fever, suspected bleeding or signs of shock require urgent veterinary contact. An educational article cannot triage the individual case remotely. An acute change needs direct assessment; delaying treatment for another serious condition because ulcers are assumed can be costly and dangerous.
| Observation | What does it mean? | Professional next step |
|---|---|---|
| Slower eating | A general sign, rather than a diagnosis | Assess teeth, feed and general health |
| Poor performance | Several possible causes | Comprehensive review beyond the stomach |
| Girth sensitivity | May be gastric, muscular or behavioural | Assess saddle, back and veterinary findings |
| Recurring colic | Requires structured investigation | Veterinary contact and an episode record |
| Improvement after medication | Does not establish lesion location or cause | Avoid treating a trial as a lasting diagnosis |
Gastroscopy: turning suspicion into a treatment map
Gastroscopy is the reference method for confirming lesions and examining their location and severity. Preparation must follow the veterinarian’s instructions, because retained feed can obscure important regions. A long endoscope is passed into the stomach under veterinary supervision to examine the squamous mucosa, margo plicatus, glandular regions and pylorus as thoroughly as possible.
The value of gastroscopy goes beyond a yes-or-no answer. It shows whether lesions are squamous or glandular, localised or extensive, and whether thickening, bleeding or changes around the pylorus are present. These details guide treatment, risk management and follow-up. A useful report retains dated images and clear locations rather than only a general description.
Grading helps monitor squamous disease and compare examinations, but a number does not replace a description. Small differences between grades may reflect viewing angle or preparation quality; extensive changes in location or appearance may matter more. For glandular disease, describing appearance and location is often more useful than compressing everything into one score.
Interpret the findings with the history. If a horse trains before feeding, travels frequently and receives two large concentrate meals, gastroscopy confirms damage but does not finish the investigation. The management system still needs redesign to reduce recurrence. Prescribing medication while retaining the same risk environment can turn treatment into a recurring expense.
Repeat gastroscopy is neither an automatic requirement for every case nor an unnecessary luxury. The veterinarian considers lesion type and severity, response, continuing training and the need to confirm healing before changing the plan. Symptoms alone do not establish healing: behaviour may improve for several reasons while lesions remain.
Alternative investigations, blood tests and faecal tests do not provide the same anatomical map. They may help assess other causes or general health, but do not replace direct inspection when the question concerns gastric lesions and their location. Marketing claims cannot make an unvalidated test a diagnostic standard.
Responsible treatment and the causes of recurrence
Treatment is a veterinary decision because the two conditions behave differently and because the horse’s health, concurrent medication and competition rules affect choice and timing. Acid-suppressing medication, mucosal protectants and other options may form part of the plan. Product, dose and duration must be determined by the veterinarian using appropriately licensed products available locally.
Uncontrolled treatment can target the wrong condition, conceal another cause of poor performance or fail because of administration problems or an unreliable product. Different formulations and bioavailability mean the same chemical name does not guarantee equivalent effectiveness. Product origin, correct storage and timing are part of treatment quality.
Reducing repeated acid exposure is central to managing squamous disease: review forage gaps, starch intake, meal size and exercise. Glandular disease may require a different approach or longer follow-up. A protocol for one racehorse should not be copied unchanged to a show mare or growing foal.
Write the plan on one page: diagnosis and lesion location, prescribed treatment, who administers it and when, storage instructions, dietary changes, exercise limits, warning signs, contact arrangements and review date. This reduces errors between trainer, groom and owner and helps prevent missed medication or feeding decisions that conflict with the plan.
For competing horses, the responsible veterinarian must check the organiser’s medication rules and applicable withdrawal guidance. A health treatment does not remove compliance obligations, and rules vary between jurisdictions and events. Use the current rules for the specific competition rather than another stable’s experience or an old publication.
Monitor response against criteria agreed in advance: appetite, weight, behaviour, performance and episodes of discomfort. Seems better is an initial observation rather than a complete assessment. If progress differs from what the veterinarian expected, reconsider the diagnosis and plan rather than automatically increasing treatment.
Feeding and training around the horse’s needs
Horses are adapted to consume small amounts of fibrous feed through much of the day. Long periods without forage are an important weakness, particularly for the squamous region. The objective is measured, regular access to suitable forage that matches quality, bodyweight and metabolic needs, while avoiding unnecessary interruptions.
Before exercise, the professional team may recommend an appropriate amount of forage to support a fibrous barrier and saliva production, where the individual horse has no contraindication. This is not a universal prescription. Metabolic disease, chewing difficulty or choke risk can require different arrangements. The nutritionist and veterinarian must balance gastric management against other risks.
Review both the size of starch- and sugar-rich concentrate meals and total daily intake. A horse needing substantial energy may benefit from distributed meals and suitable alternative energy sources rather than one large intake. Introduce dietary changes gradually: an attempt to protect the stomach should not destabilise the hindgut.
Clean water, salt provision and management of sweating support general health, but water is not an ulcer treatment. A supplement carrying the word gastric is not sufficient evidence either. Ask for product-specific research, transparent composition and quality control, including which horses and disease type were studied. A supplement does not replace established treatment for diagnosed lesions.
Training should include recovery days, progressive loading and avoidance of unnecessary repeated intense work. Record session intensity and duration, travel and periods without forage. Combined observations may reveal that recurrence follows a particular disruption: a long journey, early exercise before feeding or a multi-day competition.
Movement, social contact and reduced isolation support welfare and may reduce stress, but implementation depends on the horse and facility. An unstable group can stress some horses more than a suitable companion arrangement. Seek a predictable environment supporting feeding, movement and rest, rather than one slogan applied to every stable.
| Management point | Common risk | Measurable correction |
|---|---|---|
| Forage | Long gaps without eating | Record exhaustion times and redistribute allowances |
| Concentrates | Large starch-rich meals | Weigh portions and distribute meals with specialist advice |
| Exercise | Intense work on an empty stomach | Review feed and exercise timing |
| Travel | Disrupted routine, water and forage | Written travel plan and intake monitoring |
| Rest | Restricted movement or prolonged isolation | Safe turnout and companionship arrangements |
| Follow-up | Reliance on impressions | Document weight, appetite and behaviour regularly |
The stable protocol: from suspicion to preventing recurrence
Where the case is not urgent, start by collecting a short baseline record rather than changing everything at once. Record meal times and forage exhaustion, weighed concentrate amounts instead of scoop estimates, turnout, workload, travel, medication, appetite, manure and behaviour. The purpose is to create a timeline the veterinarian can interpret, without postponing necessary assessment.
After diagnosis, bring the team together briefly. The veterinarian explains what has and has not been established, the trainer converts recommendations into a schedule, the groom confirms practical details and the owner provides the necessary resources. A plan requiring extra forage that never arrives at weekends remains a paper plan rather than a working system.
Use a simple daily checklist: was forage available, was water consumed, was medication given as prescribed, did new behaviour appear, and did manure change? Good management does not need a complicated application. It needs consistent fields completed by the person closest to the horse and accessible to the team.
When travelling, take familiar feed where regulations permit and plan water, rest stops and ventilation. Do not introduce a new concentrate on the evening before competition. Monitor forage access in waiting areas, where hours without feed can pass unnoticed. Sudden change, stress and fasting can otherwise accumulate on the same day.
Define signs of plan failure in advance: renewed feed refusal, weight loss, pain, repeated decline or lack of improvement by the agreed review point. Contact the veterinarian if they occur and examine adherence before concluding that treatment is ineffective. Missed administrations, unsuitable timing or unchanged risk factors may explain an apparent failure.
After healing, do not return immediately to the former routine. Reducing or changing treatment requires veterinary direction, while beneficial management changes should continue. Success is measured through reduced recurrence, stable appetite and weight, and sustainable training, alongside any improvement documented on gastroscopy.
Review the programme regularly and when season, trainer, feed or travel pattern changes. Risk is dynamic: the same horse at pasture during rest differs from that horse in an intensive campaign. Use its history to anticipate higher-risk periods and discuss prevention with the veterinarian before signs reappear.
Compare the cost of management-based prevention with investigation, treatment and missed competition. Extra forage distribution points or staff training may appear to add expenditure, but can reduce execution errors and support the welfare of the whole group. A sound decision improves the system rather than treating one horse and forgetting the environment in which the problem developed.
Aletaq Golden Advice
Improved appetite after an empirical treatment should not close the diagnostic file. Ask which gastric region was affected, which risk factor changed, and how healing and recurrence will be assessed. Medication creates an opportunity for recovery; management helps preserve it.
Gastric disease is neither a judgement on the horse nor an explanation for every poor performance. Its practical value is as a signal to examine management. Identifying the affected region through gastroscopy and reviewing feeding, training, travel and welfare can turn repeated treatment into a measurable improvement programme. Does your stable record forage interruptions, workload and appetite in a way that allows them to be compared? Discuss the individual horse with its veterinarian, and subscribe to Aletaq’s weekly newsletter for further evidence-based guides.