Haemodynamics of the jugular vein in the giraffe

Controversy cotinues over the haemodynamics of the circulation to and from the head of the giraffe. The recent study by Hargens et al. provides new information explaining the absence of oedema in the legs of the ambulant giraffe. But in sedated, standing giraffes the pressure gradient down the jugular vein is about one-tenth of, and in the opposite direction to, that expected for a standing column of blood. Hargens et al. suggest that compartmentalization of the blood in the vein is involved. This seems unlikely as the valves in the vein open towards the heart.

Last Updated
January 26, 2021
Size
251.93 KB