Comparison of blood counts in splenic, renal and mesenteric arterial and venous blood in post-pubertal rabbits

Objectives: To compare blood counts between arterial and venous blood to and from visceral organs and indirectly look into the function of the organs. Methods: Splenic, renal and superior mesenteric arterial and venous blood samples were obtained from the arteries and veins in 38 post-pubertal rabbits and blood profile, including complete and differential blood counts, haemoglobin concentration and haematocrit, were measured with an automatic haematology analyser. Results and conclusions: The rabbit spleen released a large amount of leucocytes (both lymphocytes and granulocytes) into the splenic venous blood (a venous increase of 33% in total leucocyte count), and also received more leucocytes (36–58% more in terms of concentration) from the artery than the kidney or intestine. Significantly fewer red blood cells were present in the renal venous blood than in the arterial blood (a venous reduction of 5% in erythrocyte count), but it remains to be clarified why and how the reduction was induced. More than 3–4% of water might be taken into the mesenteric venous blood during microcirculation (a venous reduction of 3–4% in erythrocyte-related parameters) and a significant number of leucocytes (mainly large leucocytes) in the mesenteric blood capillaries might migrate into the surrounding intestinal tissue (a venous reduction of 13% in leucocyte count).