Table 2. Excisional wounding.

Step	Procedure	Troubleshooting
1	Prepare surgical field with heating pad set at 40 °C, surgical drape, and anesthesia system.	To limit anesthesia time for mice, accurate preparation is essential.
2	Anesthetize mouse with isoflurane at a flow rate of 5% in 100% oxygen (flow rate 1 L/min).	Monitor mouse carefully and take out of anesthesia box immediately when sufficient level of anesthesia has been reached. Exposure to high flow rates of isoflurane for too long can cause death.
3	Inject buprenorphine SR 0.5 mg/kg subcutaneously 5 min prior to incision and apply ophthalmic ointment on both eyes.	Do not start surgery immediately after injecting buprenorphine, as activation period needs to be accounted for.
4	Maintain anesthetized state with 1%–1.5% isoflurane; monitor mouse every 90 s for changes in breathing rate.	Maintaining flow rate as low as possible, but as high as necessary is imperative. An insufficient flow rate will cause peri-surgical awakening; however, an excessive flow rate will cause death during anesthesia.
5	Place mouse in a prone position on prepared surgical table.
6	Shave complete dorsum of mouse from the neck to the root of the tail and to the sides; shave until the beginning of all four extremities.	Make sure to shave a sufficient area, as Vetbond will not stick to unshaved skin.
7	Apply depilatory cream on the shaved area for 30 s. Use wet gauze swabs to remove all remaining cream and fur.	Do not leave depilatory cream on for longer than 30 s. Leaving it on too long will cause skin irritations that will likely result in wound dehiscence in a later stage.
8	Disinfect skin with three alternating betadine and alcohol wipes in a circular fashion.
9	Place sterile drape over the mouse, leaving the surgical area free.
10	Use biopsy punch to outline pattern for excision of skin on the dorsum of the mice (Figure 1B).
11	Create two wounds on the dorsum of the mice with biopsy punch.
12	Push the biopsy punch firmly onto the skin and then twist fairly quickly in swift circulating motions to cut through the dermis.	Fixate skin between fingers to create tension on the skin in order to excise biopsy. Do not push too hard or you will wound the underlying muscle. Wet the skin with an alcohol swab to ease friction forces from the biopsy punch.
13	Excise skin.	Scissors can be used to aid excision of skin if necessary.
14	Take out the splint from ethanol bath and let it dry on sterile surgical area.	Let splint fully dry before applying Vetbond.
15	Apply minimal amounts of Vetbond to the splint and place it carefully around the wound.	Leave an area of the split without Vetbond for forceps to grab. Otherwise, the splint will be glued to the forceps. Make sure to apply enough Vetbond on the silicone splints, so the splint sticks well to skin, but care must be taken to not apply Vetbond onto the wound.
16	Use 6-0 sutures to apply eight interrupted sutures fixating the splint to the surrounding skin (Figure 1B).
17	Take a picture of the wound with a ruler for documentation and baseline for analysis of wound closure.	Be sure to try and always take the images at the same angle, orientation, and distance from each wound to promote consistency.