Ann Kristin Barton

The accumulation of sand in the abdomen is a rising risk for colic in horses. Sand mainly accumulates in the ascending colon in the cranioventral abdomen. Evacuation of sand is facilitated by the application of psyllium supported with a laxative via nasogastric intubation. Laxatives currently used are either sodium sulfate/magnesium sulfate or mineral oil. The aim of this study was to compare the efficiency of polyethylene glycol, a laxative already used in human medicine for chronic constipation, with that of the above-described, established therapy options. Therefore, 44 horses diagnosed with sand enteropathy were randomly assigned and received psyllium in combination with either sodium sulfate, mineral oil or polyethylene glycol for four days. Pre- and post-therapy radiographs were assessed using a modified scoring system of Keppie et al. and Kendall et al. Adverse side effects during treatment were recorded and compared between treatment options. Median score reduction of sodium sulfate was −2 points, of polyethylene glycol −3.5 points and of mineral oil −2.5 points. Sand severity score was significantly reduced following all treatment options (p < 0.001), but did not differ between groups (p = 0.428). As all therapy regimens were successful in eliminating sand, polypropylene glycol might be the best option, as no adverse effects have been described in the literature or were seen in this study.

Sand enteropathy describes pathophysiological conditions of the equine gastrointestinal tract due to the uptake and accumulation of sand. It is an increasingly recognized cause of gastrointestinal disease in arid geographic areas. Clinical signs can vary widely from colic, fever and inappetence to poor performance. Diagnosis based solely on clinical signs is nearly impossible. The current literature describes a variety of diagnostic aids, with radiographic imaging considered the gold standard. Therapeutic approaches aim at the evacuation of sand from the abdomen. This can be achieved by the administration of psyllium in connection with a laxative via nasogastric intubation. Several studies describe varying laxatives such as mineral oil or sodium-/magnesium sulphate. This narrative review includes 39 publications up to the year 2026. We aim to raise awareness among practicing veterinarians and highlight new research objectives to improve knowledge and treatment of gastrointestinal diseases related to sand accumulation.

Summary: The term Equine Gastric Ulcer Syndrome (EGUS) has been used since 1999. As there are important differences, the terms Equine Squamous Gastric Disease (ESGD) and Equine Glandular Gastric Disease (EGGD) were introduced in 2015. Risk factors like dietary management, training regimens and drug side effects, as described for NSAIDs, predispose horses to ESGD or EGGD. To date, gastroscopy remains the gold standard for a reliable diagnosis. However, there are new diagnostic approaches using less invasive biomarkers. Based upon current best evidence, the proton pump inhibitor omeprazole is the treatment of choice for both ESGD and EGGD. Alternative nonpharmacological treatments have been investigated due to the high cost of approved omeprazole, long‐term adverse effects in humans and the restriction on omeprazole use in some equestrian sports. An update on diagnosis, nonpharmacological treatment options and prevention of ESGD/EGGD is the focus of this review.

Mild–moderate equine asthma (MEA) is a very common but underdiagnosed pulmonary disease in horses, with mild cases not showing clinical respiratory signs. This study evaluates the influence of a standardized lunging exercise test (SLET) on bronchoalveolar lavage fluid (BALF) cytology in MEA horses. We hypothesized that SLET would increase the total nucleated cell count (TNCC) and/or percentages of inflammatory cells associated with EA. In a prospective, randomized, non-blinded, between-subjects study design of two independent groups, 39 horses (17 mild and 22 moderate) were included. They were chosen out of a cohort of horses undergoing respiratory investigations (history, clinical examination, and clinical pathology (white blood cells (WBC) and arterial blood gas analysis (aBGA)) consistent with MEA, using a scoring system in a clinical setting of an equine referral clinic. Bronchoalveolar lavage (BAL) was performed 30 min post-SLET in 16 randomly chosen horses. The other horses underwent BAL without SLET. The SLET resulted in a statistically significant increase (p < 0.001) in the proportions of neutrophils in BALF cytology, and in an increased chance of confirmation of the presumed diagnosis in horses with mild phenotypes (p < 0.001, OR = 8.00, CI = 1.28–50.04), while moderate phenotypes were less frequently diagnosed. Exercise had no association with cytology across all horses. Unexpectedly, the SLET group of horses with a moderate phenotype had a statistically significant lower TNCC (p = 0.035). In conclusion, an SLET prior to BAL might increase the chance of an MEA diagnosis.

In den letzten Jahren hat die Forschung zu PSSM und MFM große Fortschritte gemacht. In diesem Artikel werden die verschiedenen belastungsassoziierten Myopathien sowie die neuen, detaillierteren Empfehlungen im Bereich Diagnostik und Therapie mit besonderem Fokus auf Warmblutpferde dargestellt. Article published online: 17 June 2025 © 2025. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

The term Equine Gastric Ulcer Syndrome (EGUS) has been used since 1999. As there are important differences, the terms Equine Squamous Gastric Disease (ESGD) and Equine Glandular Gastric Disease (EGGD) have been introduced in 2015. Risk factors like die-tary management, training regimens and drug side effects, as described for NSAIDs, predispose horses to ESGD or EGGD. To date, gastroscopy remains the gold standard for a reliable diagnosis. However, there are new diagnostic approaches using less in-vasive biomarkers. The proton pump inhibitor omeprazole is currently recommended by the American College of Veterinary Internal Medicine and the European College of Equine Internal Medicine (ACVIM/ECEIM) for the treatment of both ESGD and EGGD. Omeprazole per os is much less effective in treating EGGD, so it is often combined with sucralfate, which forms a protective mucosal barrier to shield it from the gastric acid. Intramuscular application of omeprazole has been shown to increase efficacy in EGGD therapy. Alternative non-pharmacological treatments have been investigated due to the high cost of approved omeprazole, long-term adverse effects in humans and the re-striction on omeprazole use in some equestrian sports. An update on diagnosis, treat-ment and prevention of ESGD/EGGD is the focus of this review.

This literature review focuses on diagnostics of equine asthma (EA), possible influencing factors on diagnostic techniques and latest developments in diagnosing horses during EA remission or with subclinical disease. Routine EA diagnostics include a clinical examination of the respiratory system with percussion and auscultation including a rebreathing examination, and clinical pathology including white blood cells and arterial blood gas analysis. Subsequent diagnostics include bronchoscopy to evaluate the amount and viscosity of respiratory secretion, bronchoalveolar lavage, and the cytology of tracheal aspirates (TAs) and bronchoalveolar lavage fluid (BALF). The grading of EA severity is built on respiratory effort at rest, which is increased in severe equine asthma. The inflammatory subtype is based on BALF cytology, while TA cytology helps to rule out previous bacterial infections. Different factors have an impact on the airways regarding the structure of the epithelium, cytology, and inflammatory markers possibly influencing the diagnosis of EA. Short-term exercise increases the total cell count and inflammatory mediators identified in the BALF of human patients, asymptomatic horses, and other species. Other factors involve cold or chlorinated air, long-term training effects, and concurrent additional respiratory disease, in particular exercise-induced pulmonary hemorrhage. As BALF cytology may be unremarkable during EA remission and low-grade disease, exercise tests and other factors stressing the bronchial epithelium may help to diagnose these patients.

Gastric pH is a key factor in the development of equine squamous gastric disease (ESGD). Although acid injury is unlikely the primary cause of equine glandular gastric disease (EGGD), low pH may promote mucosal damage. Gastric pH is influenced by roughage uptake, as chewing increases the alkaline saliva production. The proton pump inhibitor omeprazole is currently recommended by the American/European College of Veterinary/Equine Internal Medicine (ACVIM/ECEIM) for ESGD and EGGD. We hypothesized that dental disorders decrease saliva production and gastric pH, predisposing horses to EGUS. Gastroscopy, intragastric pH measurement and dental examinations were performed (n = 54). Omeprazole therapy was recommended (n = 32), dental disorders were corrected (n = 22) and gastroscopy was repeated 4 weeks later (n = 9). An influence of moderate to severe dental disorders on ESGD (grade ≥ 2/4) (p = 0.394) and EGGD (grade ≥ 2/3) (p = 0.857) could not be determined. Nevertheless, there was a trend that moderate to severe dental disorders were associated with a low gastric pH ≤ 4 (p = 0.100). Horses with no or mild dental problems had a mean pH of 5.4 versus 4.2 in moderate to severe dental disorders. In conclusion, our study results do not show a direct relationship between dental disorders and EGUS, but a gastric and oral cavity examination should still be considered in patients presented for weight loss or inappetence.

Gastric pH seems to be a key factor for the development of Equine Gastric Ulcer Syndrome (EGUS). It is influenced by the amount and duration of roughage uptake, as chewing increases the production of alkaline saliva. The protone-pump-inhibitor omeprazole is currently recommended by the American College of Veterinary Internal Medicine/European College of Equine Internal Medicine (ACVIM/ECEIM) consensus statement for therapy of both Equine Squamous Gastric Disease (ESGD) and Equine Glandular Gastric Disease (EGGD). We hypothesized that dental disorders decrease saliva production due to altered chewing and in consequence gastric pH, therefore predisposing horses to EGUS. In 54 horses, a gastroscopy with measurement of the intragastric pH after 12 hours of fasting and an examination of the oral cavity were carried out. Omeprazole therapy was recommended (n=32), dental disorders were corrected (n=22) and gastroscopy was repeated 4 weeks later (n=9). No influence of moderate-severe dental disorders on ESGD (grade ≥2/4) (p = 0.394) and EGGD (grade ≥2/3) (p = 0.857) could be determined. Nevertheless, there was a trend that moderate- severe dental disorders were associated with a low gastric pH (1-4) (p = 0.100). In conclusion, we found no evidence that gastroscopy should be recommend in horses with dental disorders and vice versa.

This literature review focusses on diagnostics of Equine Asthma (EA), possible influencing factors on diagnostic techniques and latest developments in diagnosing horses during EA remission or in case of subclinical disease. Routine EA diagnostics include clinical examination of the respiratory system including percussion and auscultation, clinical pathology including white blood cells and arterial blood gas analysis, bronchoscopy to evaluate the amount and viscosity of respiratory secretion, bronchoalveolar lavage and cytology of tracheal aspirates (TA) and bronchoalveolar lavage fluid (BALF). Grading of EA severity and inflammatory subtype is based on BALF cy-tology, while TA cytology helps to rule out previous bacterial infections. Different factors have an impact on the airways regarding structure of the epithelium, cytology and inflammatory markers possibly influencing the diagnosis of EA. Short-term exercise increases the total cell count and inflammatory mediators in BALF of men, asymptomatic horses and other species. Further factors involve cold or chlorinated air, long-term training effects and the co-incidence of further respir-atory disease, in particular exercise-induced pulmonary hemorrhage. As BALF cytology may be unremarkable during EA remission and low-grade disease, exercise and other factors stressing the bronchial epithelium may help to diagnose these patients.