OUTLINE
Although in the Review Article : "Idiopathic Thrombocytopenic Purpura: A practice Guideline Developed by Explicit Methods for the American Society of Hematology" bleeding time is considered as unnecessary/inapropriate to establish the diagnosis of ITP it's still used in experimental models of ITP study as an additional test.
PROTOCOL
Anesthesize a mouse
Make a standard incision on the dorsal tail vein using Simplate blades
Immerse the tail in NaCl 0.9% at 37.5ѓC
Record the time from the moment blood is observed to emmerge from the wound until cessation of blood flow
ADDITIONAL INFO
Alternatively you can perform a standard incision with an automatic device (Surgicutt; ITC, Edison, NJ) and every 15 secs apply a filter paper (Whatman 3MM) for 5 sec until the blood no longer stained it.
REFERENCES
Consequences of GATA-1 deficiency in megakaryocytes and platelets. Carl W; Jackson et al. Blood Vol.93 No9 May 1) 1999 : pp2867-2875