Submental Blood Collection in Mice
IACUC Standard Procedure
Effective Date: August 2024
Submental blood collection (Chin Bleed) is an acceptable alternative to the submandibular method. This method allows for maximum allowable sample volume with minimal trauma to the animal. Submental collection may be easier to perform due to the direct visibility of the target vessels, which are located in a sparsely furred region. This technique must be performed on anesthetized animals. Only trained personnel may perform this procedure.
This technique may yield a moderate sample volume (100-200µl), so will not be appropriate for frequent small blood volume collection. Multiple samples can be taken by alternating sites. For information regarding maximum blood collection volume please refer to the UCSF Blood Collection Guidelines.
Supplies:
- Isoflurane anesthesia system
- 4-5 mm lancet or 25–27-gauge needles
- Gauze sponges
- Lubricant
- Blood collection tube
Procedure:
- Anesthetize the mouse with isoflurane in an induction chamber.
- Flush the chamber with oxygen to reduce isoflurane exposure and then open chamber.
- Remove the mouse from the induction chamber and restrain the mouse with the non-dominant hand by grasping the loose skin over the shoulders and behind the ears; the skin should be taut under the chin (submental region), but no so tight as to restrict breathing.
- Apply sterile lubricant to the ventral chin to improve visibility of the vessels and locate the puncture site (the vessels should be visible approximately 0.5 cm rostral and lateral toward the lower jaw).
- Prick the blood vessel (linguofacialis vein firmly using the sterile lancet or needle tip (1-2mm depth). Blood will flow immediately.
- Collect sample with a pipette or other collection tube, until the target volume is reached.
- Bleeding typically stops automatically when the mouse is released and the head position goes back to normal. Mild pressure can be applied with a sterile gauze sponge if needed.
- The animal may be returned to their home cage once they have fully recovered from the anesthesia and ensure that all animals have stopped active bleeding before returning cage to the rack.
Agents
This procedure requires gas anesthesia. Add anesthesia agents under section I.1. All agents administered to animals should be listed in the "Agents" section of RIO.
Procedure Examples
Adverse Effects
Hemorrhage from the oral or nasal cavity, hematoma formation, infection.
References
Constantinescu, G.M and Dufee, N.M. (2017). Letter to the Editor: Comparison of Submental Blood Collection with the Retroorbital and Submandibular Methods in Mice (Mus musculus). JAALAS, Nov; 56(6):711-712. PMC: 5710148
Regan, R.D., Fenyk-Melody, J.E., Tran, S.M., Chen, G., Stocking, KL. (2016). Comparison of Submental Blood Collection with the Retroorbital and Submandibular Methods in Mice (Mus musculus). JAALAS, Sept; 55(5):570-576. PMC: C5029828