Healthy mares were administered phenylephrine to induce transient polycythemia secondary to splenic contraction. Data was collected at baseline (T0), 5 minutes (T1) and 2 hours (T2) post-phenylephrine infusion. Collected data included baseline CBC, chemistry, fibrinogen, and serum amyloid A; at each time point viscoelastic coagulation profiles (VCM Vet), traditional in-vitro coagulation profiles, and ultrasonographic measurements of the spleen were obtained.