The effect of exploratory celiotomy and associated management on equine gastric ulceration

<jats:p>&lt;b&gt;Background:&lt;/b&gt; Equine Gastric Ulcer Syndrome (EGUS), comprising Equine Squamous Gastric Disease (ESGD) and Equine Glandular Gastric Disease (EGGD), is an important consideration in horses undergoing exploratory celiotomy for colic due to exposure to risk factors. The prevalence and progression of EGUS during the immediate post-operative period remains poorly characterized. &lt;b&gt;Objectives:&lt;/b&gt; Determine the prevalence of EGUS following exploratory celiotomy for colic and identify factors associated with ulcer development and progression after surgery. &lt;b&gt;Study Design:&lt;/b&gt; Prospective cohort clinical study. &lt;b&gt;Methods:&lt;/b&gt; Gastroscopy was performed in adult horses within 5–25 hours of recovery from exploratory celiotomy (T1, n = 41) and repeated 5–7 days post-operatively (T2, n = 28). ESGD and EGGD scores were compared using an ordinal logistic mixed-effects regression model. Potential risk factors included omeprazole administration, refeeding protocol, post-operative gastrointestinal complications, surgical lesion type, colic duration, fasting duration, pre-operative medical management, and duodenal biopsy histopathology scores. &lt;b&gt;Results:&lt;/b&gt; At T1, 78% (32/41) of horses had ESGD scores ≥2 and 38% (11/29) had EGGD scores ≥1. At T2, 89% (25/28) had ESGD scores ≥2 and 52% (14/27) had EGGD scores ≥1. ESGD scores increased significantly over time (χ&lt;sup&gt;2&lt;/sup&gt;(1) = 6.8, &lt;i&gt;p&lt;/i&gt; = 0.009), whereas EGGD scores did not (χ&lt;sup&gt;2&lt;/sup&gt;(1) = 0.2, &lt;i&gt;p&lt;/i&gt; = 0.6). Post-operative omeprazole (1–4 mg/kg) significantly reduced ESGD worsening (χ&lt;sup&gt;2&lt;/sup&gt;(2) = 12.5, &lt;i&gt;p&lt;/i&gt; = 0.002). No significant associations were found between ESGD or EGGD progression and lesion type, colic duration, fasting duration, refeeding protocol, or histopathology scores. Gastrointestinal complications showed a trend toward increased ESGD scores (&lt;i&gt;p&lt;/i&gt; = 0.054) but not EGGD. &lt;b&gt;Main Limitations:&lt;/b&gt; Small sample size, unknown pre-operative EGUS status, and variation in EGUS grading and post-operative management. &lt;b&gt;Conclusions:&lt;/b&gt; Horses undergoing exploratory celiotomy are at increased risk of post-operative ESGD progression. Omeprazole administration reduced the likelihood of worsening ESGD, whereas EGGD did not significantly progress during hospitalization.</jats:p>