Techniques for blood collection from the rat include puncture of the heart, retro-orbital plexus, jugular vein, saphenous vein, tail blood vessels, carotid artery, abdominal aorta, and vena cava.

She then massages the 'swelled' injection area gently with a piece ... minutes to relax before catheterization of the tail vein. Most of the rats quickly become very relaxed and resume normal ...