Thromboelastography testing in mice following blood collection from facial vein and cardiac puncture

: Blood collection is critical for mouse research studies particularly in hemostatic testing. Cardiac puncture; a standard effective method requires anesthesia and is a terminal procedure while facial vein technique allows multiple collections. Thromboelastography (TEG) is a global hemostasis test, provides a dynamic real-time picture of coagulation. However, TEG experiments in mice require large number of animals and may not allow pre/postinterventions assessment. In this study, we aimed to investigate the feasibility of facial vein sampling for TEG analysis as an alternative to cardiac puncture and examined the impact on coagulation results. Blood samples were obtained from a total of 10 C57BL/6 and CD-1 mice via cardiac puncture and a total of another eight mice of similar strains via facial vein sampling. We compared TEG parameters in both methods using descriptive statistics and the Student t test. Results show no significant difference in any of the TEG parameters between cardiac and facial vein blood indicating the two methods are comparable. Facial vein sampling provides a less costly alternative to cardiac puncture. It is a suitable blood collection method for pre/postinterventions or follow-up studies and it better addresses reduction and refinement goals in mouse studies. A larger study to evaluate the sex or strain and genetic background differences will be valuable.