How to correctly give an injection to a rat? - briefly
Use a sterile 27‑30 G needle, gently restrain the rat, locate the lateral tail vein or a subcutaneous site, and inject the calculated volume steadily. Verify placement by confirming low resistance and no leakage.
How to correctly give an injection to a rat? - in detail
Administering a parenteral injection to a laboratory rat requires preparation, restraint, correct site selection, needle handling, and post‑procedure monitoring.
First, gather sterile equipment: appropriate‑gauge needle (typically 25‑27 G), syringe calibrated for the required volume, antiseptic swabs, disposable gloves, and a sharps container. Verify dosage calculations based on the animal’s weight and the pharmacological concentration. Prepare the injection solution using aseptic technique and label the syringe with drug name, concentration, and volume.
Second, restrain the animal safely. Place the rat on a padded surface, grip the tail with the thumb and forefinger while supporting the body with the opposite hand. Apply gentle pressure to the scruff of the neck with the thumb of the supporting hand to induce a brief immobilization without causing stress.
Third, select the injection site. For subcutaneous administration, lift a fold of loose skin on the dorsal cervical region; for intraperitoneal injection, locate the lower right quadrant of the abdomen, avoiding the midline and the urinary bladder.
Fourth, disinfect the chosen area with an alcohol swab, allowing it to evaporate. Insert the needle at a 45‑degree angle for subcutaneous delivery, bevel up, penetrating the skin just enough to enter the subcutaneous space. For intraperitoneal injection, use a 90‑degree angle, bevel down, advancing until a slight “pop” indicates entry into the peritoneal cavity.
Fifth, deliver the calculated volume steadily. Withdraw the needle promptly, applying gentle pressure to the injection site with a sterile gauze to minimize leakage. Release the animal, observe for normal respiration and mobility, and return it to its cage.
Finally, dispose of the needle and syringe in a designated sharps container, record the procedure details in the animal log, and monitor the rat for any adverse reactions over the ensuing hours.