Abstract
A total of 69 fowls were examined to describe and illustrate the renal portaland venous systems. The kidney of the fowl receives venous blood from the V. iliacaexterna, V.ischiadica and V.iliaca interna. These three vessels anastomose with theV. portae renalis media et caudalis and form the renal venous circulation (Fig. 1). By wayof this circulation the kidney receives venous blood from the portal veins. The newnomenclature Circulus venosus renis is proposed.The V. portae renalis cranialis courses cranialward, giving branches to all the directionsin the Divisio renalis cranialis, and anastomoses with the vertebral vein or sinus at twopoints. In the Divisio renalis media the V. portae renalis media has large branches whichrun dorsolaterad. In the Divisio renalis caudalis, the V. portae renalis caudalis has brancheswhich run in all the directions.The ramifications of the V.intervertebra1is in the Divisio renalis media et caudalisanastomose with the V. vertebralis at several points. They contribute to the formation ofthe Circulus venosus renis.The lobules of the kidney are divided into two types, Japanese fan-shaped and fig-shapedlobules. In the former type, the V. intralobalis run parallel with the kidney surface inthe Lobulus corticalis, giving off the V. centralis at an interval. In the latter type, theV.centra1is is derived directly from the V.interloba1is or from the V. intralobalis andenters the lobulus from its basis.The directions of arterial and venous blood flows in the parezuchyma of the kidney aresummarized in the following table.
