How can you operate on mice? - briefly
Surgical procedures on laboratory mice involve anesthesia (commonly inhalational isoflurane or injectable ketamine‑xylazine), sterile preparation of the operative site, and microsurgical techniques using fine instruments and a stereomicroscope; post‑operative care includes analgesia, monitoring, and appropriate housing to ensure recovery.
How can you operate on mice? - in detail
Performing surgical procedures on mice requires strict adherence to aseptic technique, precise anesthesia management, and careful postoperative monitoring.
Begin with health assessment and acclimatization of the animal. Verify weight, temperature, and hydration status; exclude individuals with signs of infection or illness. Maintain a clean environment and use sterilized cages for recovery.
Select an appropriate anesthetic regimen. Inhalational agents such as isoflurane (1–3 % in oxygen) provide rapid induction and adjustable depth. For injectable protocols, combine a sedative (e.g., ketamine 80–100 mg kg⁻¹) with a tranquilizer (e.g., xylazine 5–10 mg kg⁻¹). Monitor respiratory rate, heart rate, and reflexes throughout the procedure; apply a heating pad to preserve body temperature.
Prepare the surgical field. Shave the intended site, apply a depilatory cream if necessary, then disinfect with alternating swabs of povidone‑iodine and 70 % ethanol. Use sterile drapes to isolate the area.
Employ microsurgical instruments designed for rodents: fine scissors, forceps, micro‑needle holders, and a stereomicroscope for magnification. Choose sutures appropriate for the tissue size—typically 6‑0 or 7‑0 absorbable material for internal closure and 5‑0 non‑absorbable for skin.
Standard steps for a typical abdominal operation include:
- Midline skin incision (5–8 mm) using a scalpel.
- Separation of subcutaneous tissue with blunt dissection.
- Exposure of the peritoneum and entry with a micro‑scalpel.
- Execution of the intended manipulation (e.g., organ resection, tumor implantation).
- Hemostasis with micro‑cautery or absorbable gelatin sponges.
- Layered closure: peritoneum with a single interrupted suture, muscle layer if present, and skin with a simple interrupted or subcuticular stitch.
For cranial procedures, secure the mouse in a stereotaxic frame, expose the skull, and drill a burr hole at the predetermined coordinates. Apply sterile saline to prevent overheating, then insert the probe or implant device. Seal the opening with bone wax and close the incision as described above.
Administer analgesia immediately after surgery. Buprenorphine (0.05–0.1 mg kg⁻¹, subcutaneously) offers long‑lasting pain relief; consider a repeat dose every 8–12 hours for the first 48 hours. Monitor for signs of distress, wound dehiscence, or infection daily. Provide softened food and hydrogel to ensure adequate nutrition and hydration during recovery.
Maintain detailed records of anesthesia duration, surgical steps, and postoperative observations. Compliance with institutional animal care guidelines and regular review of technique improve outcomes and reproducibility.