Gravitational haemodynamics and oedema prevention in the giraffe

Because it is so tall, the giraffe, Giraffa camelopardalis, provides an important animal model for investigating adaptive mechanisms to orthostatic (gravitational) pressure changes. Previous physiological studies of the giraffe have concentrated on arterial blood pressures in the heart and neck. Briefly, these investigations revealed that arterial pressure near the giraffe heart is about twice that […]

Origin of mean arterial and jugular venous blood pressures in giraffes

Using a mechanical model of the giraffe neck and head circulation consisting of rigid, ascending, ‘carotid’ limb, a ‘cranial’ circulation that could be rigid or collapsible, and a descending, ‘jugular’ limb that also could be rigid or collapsible, we have analyzed the origin of the high arterial and venous pressures in giraffe, and whether blood […]