Fib^AEK mice display prolonged tail bleeding times and significant protection from occlusive thrombotic injury to the carotid artery. (A) Time to cessation of bleeding (>60 seconds) of WT, Fib^AEK, Fib^+/−, and Fib^−/− mice following 3-mm excision of the distal portion of the tail. Horizontal bars indicate mean times for each group. Note that 3 of 6 Fib^AEK mice and 6 of 6 Fib^−/− mice did not stop bleeding during the evaluation period. *P < .01 by Student t test; **P < .01 by Fisher’s exact test. (B) Time to stable carotid vessel occlusion as indicated by detection of flow stop using a Doppler flowmeter following FeCl₃ injury. A statistically significant difference of P < .001 was determined by Fisher’s exact test.