How do you dissect a rat? - briefly
Begin by anesthetizing the rat, positioning it supine, and making a midline incision from sternum to pelvis; reflect the skin and muscle layers to expose the abdominal cavity, then locate and isolate major organs (liver, stomach, intestines, etc.) and remove them using dissecting scissors and forceps.
How do you dissect a rat? - in detail
A rat dissection begins with compliance to institutional animal‑care guidelines and acquisition of a valid protocol approval. Required items include a dissecting tray, fine scissors, forceps, scalpel, gauze, phosphate‑buffered saline, and a stereomicroscope if detailed observation is needed.
Euthanasia must be rapid and humane. Administer an overdose of a barbiturate anesthetic (e.g., sodium pentobarbital, 150 mg/kg intraperitoneally) or use CO₂ inhalation according to approved concentrations. Confirm the absence of reflexes before proceeding.
Place the animal in dorsal recumbency on a chilled dissection board. Secure the limbs with pins to prevent movement. Perform the following incisions:
- Make a midline skin cut from the lower abdomen to the thorax using a scalpel blade.
- Reflect the skin laterally with forceps; cut through the underlying muscle layer along the same line.
- Open the thoracic cavity by cutting the sternum or separating the ribs with scissors.
- Expose the abdominal cavity by gently pulling back the diaphragm.
Organ removal proceeds as a series of precise steps:
- Locate the liver; detach it from the diaphragm and surrounding connective tissue with blunt forceps.
- Identify the heart; cut the great vessels (aorta, vena cava) and remove the organ with a scalpel.
- Isolate the stomach and intestines; sever the mesenteric attachments and extract the gastrointestinal tract.
- Extract the kidneys and reproductive organs using fine scissors to cut the renal and gonadal vessels.
Throughout the procedure, rinse tissues with cold phosphate‑buffered saline to maintain structural integrity and reduce autolysis. Collect samples in labeled vials for downstream analysis.
After completion, clean all instruments with detergent, rinse with distilled water, and sterilize. Dispose of biological waste in accordance with biosafety regulations. Document the dissection steps, observations, and any deviations from the protocol for reproducibility.