RENAL ANATOMY OF THE PYGMY HIPPOPOTAMUS (CHOEROPSIS-LIBERIENSIS) - ANOVERVIEW

The adult kidney of Choeropsis liberiensis is 74.8% cortex and 22.9% m edulla. The neonatal cortex is relatively less. A single kidney has ab out 3 x 10(6) glomeruli. These form 5% of renal mass in the adult but more so in neonates. The primary tubus maximus, TM1, follows the later al curvature of the kidney. It gives off, toward the hilum, dorso-vent rally paired secondary tubi maximi, TM2. The tubi are a single layer o f high cuboidal epithelium from which terminal collecting ducts arise throughout the surrounding inner medulla. The cranial and caudal limbs of TM1 open at a diminutive pelvis which receives a small papilla in continuity with TM1. The medulla is continuous although variably disto rted by folds of cortex at the lateral curvature of the kidney. The re nal lobes project toward the medial border and consist of cortex, medu lla and TM2. The lobar cortex is continuous with the common cortex of the lateral curvature. The kidney, although strongly lobed, has no inf undibula or rencules. A main peripheral vein courses medial and parall el to TM1. It is apparently a modified large arcuate vein and receives arcuate and interlobar tributaries. At the level of the papilla it jo ins the main renal vein. The arterial supply is mainly by interlobar a rteries but there are also sizeable external perforator arteries which branch from the main renal artery and perforate the cortex of lobes a bout the hilum. The sourse of the arteries is illustrated.