Vein retroperitoneal and runs to the right and roughly parallel to the abdominal aorta along the spine. Large veins feed into these two veins, and smaller veins into these. Together this forms the venous system. Whilst the main veins hold a relatively constant position, the position of veins person to person can display quite a lot of variation. The pulmonary veins carry relatively oxygenated blood from the lungs to the heart. The superior and inferior venae cavae carry relatively deoxygenated blood from the upper and lower systemic circulations, respectively. The portal venous system is a series of veins or venules that
Tail vein "The lateral tail vein is usually used and 50 ul to 0.2 ml of blood can be obtained per sample depending on the size of the animal." Warming the animal to an ideal 39°C may be necessary to cause dilation of the veins and allow for easier processing. Tail vein Tail vein or caudal vein is the largest vein in vertebrate animals' tail. It leads directly into the posterior cardinal vein in the posterior trunk in fishes. Mammal caudal vein (the middle caudal vein) leads to inferior vena cava. Caudal vein is one of the many places from which a