PON1 and colitis: Results: Serum PON‐1 activity was significantly lower in horses with colitis (median [min‐max range] U/mL) (44.7 [3.8‐147.0]) compared to healthy horses (77.5 [11.3‐112.6]), and in non‐survivors (38.6 [3.8‐147.0]) compared to survivors (49.4 [8.8‐118.0]).