The prevalence and changes over time of equine glandular gastric disease in a teaching herd population

Abstract

Background: The natural progression of equine glandular gastric disease (EGGD) in the absence of treatment has not yet been described in the literature, nor has the prevalence in a teaching herd population been reported. Objectives: The aims of this study were to determine the prevalence of disease in a teaching population over the study period (2019–2021) and to observe the changes over time in disease severity of naturally occurring diseases (not experimentally induced) without medical intervention. Methods: Twenty-one horses underwent an initial gastroscopy and a repeat gastroscopy between 14 and 731 days later. Gastroscopy data were graded quantitatively and described qualitatively. Prevalence and 95% confidence intervals (CI) were calculated. The changes over time were determined by comparing initial and repeat gastroscopies. Results: The prevalence from initial, repeat and total number of gastroscopies was 62% (95% CI: 40.8–79.3), 71% (95% CI: 50.0–86.2) and 67% (95% CI: 51.6–79), respectively. The changes over time included worsening of disease in 29% of horses (95% CI: 13.8–50.0), improvement of disease to a lower grade in 24% (95% CI: 10.6–45.1), no change in grade in 38% (95% CI: 20.8–59.1), and complete resolution of disease to grade 0 in 10% (95% CI: 2.7–28.9). Main limitations: Limitations included a maximum of two gastroscopies per horse given COVID-19 restrictions on data collection, and highly varied interval times between initial and repeat gastroscopies. Conclusion: In conclusion, there is a high prevalence of disease in this teaching herd. The changes over time in naturally occurring diseases without medical intervention might include worsening, improvement, no change or resolution of disease.