In horses, gastrointestinal (GI) disorders are the main cause of disseminated intravascular coagulation (DIC), a potentially life-threatening condition. Large colon volvulus, colitis, and strangulating small intestinal lesions are the most common GI conditions that cause DIC in horses, 4,12 but DIC is also reported in septicemia, snakebites, rhabdomyolysis, and diffuse clostridial myonecrosis. 11,13,16,19,21,22 Significantly prolonged PT was reported in 58% of horses with acute GI crisis-associated DIC, 12 and was significantly associated with strangulating GI lesions. 3,4 Early diagnosis of subclinical DIC is crucial, and depends on laboratory testing of hemostasis. 3 Prothrombin time (PT) is commonly measured in horses to assess the status of hemostasis, specifically the extrinsic and common pathways. 21 Monitoring changes in PT over time is of diagnostic and prognostic value, as well as a clinical tool to help guide treatment. 3,4 Equine medicine is often practiced at a distance from reference laboratories. Delays in receiving hemostasis test results may be detrimental in treating critically ill horses. A reliable, cost-effective, point-of-care (POC) test to assess hemostasis, such as PT measurement, would be useful under field conditions. The CoaguChek-XS (Roche Diagnostics, Mannheim, Germany) is a small, portable POC PT analyzer, commonly used in human medicine for home monitoring of warfarin therapy, that is suitable for both venous and capillary blood samples, providing results within minutes. 17,20 Studies have assessed the reliability, precision, and suitability of the CoaguChek-XS