EXPERIMENTAL TECHNIQUES (cont)
Retroorbital bleeding is frequently performed in hamsters because the technique, if properly executed, is safe - yet moderate quantities of blood can be collected. For humane purpose, this technique must be performed only on anesthetized animals. A capillary tube is placed behind the eye and rotated in order to rupture the venous plexus in that area.
Relatively large quantities of blood can be collected by cardiac puncture. With the hamster anesthetized, pass a 22 gauge needle to the left of the sternum, angling down approximately 45 degrees through the diaphragm and puncturing the heart. (This technique can injure or even kill the animal if performed improperly or too often.)
Very small quantities of blood can be collected from lightly anesthetized hamsters by quickly snipping off a toenail and then cauterizing the area with silver nitrate or an electric cautery. For humane reasons, this procedure should be done at extended intervals.