Risk Factors for Disease in Military Working Equines.

INTRODUCTION: Diseases can impact Military Working Equids (MWEs) readiness and limit days in service. The objectives of this study are to categorize diseases in MWEs and evaluate potential risk factors for disease. MATERIALS AND METHODS: Pathology reports from MWEs from 2005 to 2025 were retrieved from the Joint Pathology Center archives. Disease processes with ≥5 cases were evaluated for potential risk factors, including MWE breed, sex, neuter status, geographic location, and age at sampling. RESULTS: Diagnoses included inflammation (n = 30), neoplasia/proliferation (n = 24), within normal limits (n = 12), trauma (n = 3), atrophy (n = 1), and necrosis (n = 1); 2 cases had 2 diagnoses each. Inflammation was most common in the skin (n = 19). The most common neoplastic diagnoses were sarcoid (n = 8) and melanocytic neoplasia (n = 5). Mustangs had nearly 8 times the odds of developing infection than other MWE breeds (odds ratio [OR]: 7.85, 95% CI, 1.50-41.10, P < .05) and more than 8 times the odds of developing bacterial infections (OR: 8.10, 95% CI, 1.20-54.82, P < .05), though this may have been an artifact of the relatively low sample size in this study. Military Working Equids from Fort Carson had 81.33 times the odds of developing melanocytic neoplasia than MWEs from other locations (95% CI, 6.82-970.22, P < .05); Fort Carson is at a high elevation, raising the possibility of UV-induced melanocytic neoplasia. CONCLUSIONS: The Joint Pathology Center is the only Department of Defense (DoD) pathology laboratory and maintains a repository capturing over 100 years of data. Future studies with larger sample sizes may yield stronger statistical associations and identify additional risk factors for diseases in MWEs.