How can an injection be given to a rat under the neck? - briefly
A dorsal cervical subcutaneous injection is administered by gently restraining the rat, cleaning the area, and inserting a 26‑30 G needle at a shallow angle into the loose skin behind the head. Deliver the prescribed volume slowly, then observe the animal for any immediate adverse effects.
How can an injection be given to a rat under the neck? - in detail
Administering a subcutaneous or intramuscular dose in the neck region of a laboratory rat requires precise preparation, proper restraint, and strict aseptic technique.
First, gather the necessary supplies: a 27–30 G needle attached to a 1 mL syringe, sterile saline for needle flushing, disinfectant (70 % ethanol), a warming pad, and a clean work surface. Verify the drug concentration and calculate the exact volume for the animal’s weight, typically 0.1 mL per 100 g body mass for subcutaneous delivery.
Second, acclimate the rat to the handling area for at least five minutes to reduce stress. Place the animal on a warming pad and gently grasp the scruff of the skin between the forepaws with the thumb and forefinger of the non‑dominant hand. This maneuver lifts the head slightly and immobilizes the neck without causing pain.
Third, locate the injection site. The appropriate area lies lateral to the midline, just caudal to the mandible and dorsal to the sternomastoid muscle. Palpate the region to ensure the skin is taut and free of hair; if necessary, shave a small patch and clean with ethanol, allowing it to dry.
Fourth, perform the injection. Hold the syringe in the dominant hand, align the needle bevel upward, and insert at a 45° angle through the skin into the subcutaneous tissue or, if muscle delivery is required, aim deeper into the underlying musculature. Advance the needle until a slight resistance is felt, then depress the plunger smoothly to deliver the calculated volume. Withdraw the needle promptly and apply gentle pressure with a sterile gauze to minimize bleeding.
Fifth, dispose of the needle in a sharps container, clean the injection site with ethanol, and return the rat to its cage, monitoring for at least five minutes for signs of distress, hemorrhage, or abnormal behavior. Record the procedure details, including drug, dose, site, and any observations, in the animal log.
Following this protocol ensures accurate dosing, minimizes tissue trauma, and complies with institutional animal care guidelines.