ウシの静脈管閉鎖の解剖学的検索

Abstract

The closure of the ductus venosus (DV) was studied in 59 cattle, ranging from a 249-dayold fetus to a 183-day-old calf. In the 249-day-old fetus, the DV was a large vein located within the papillary process of the liver. The DV originated at the confluence of the umbilical and portal veins and emptied into the posterior vena cava. At the origin of the DV, there was a thin circular fold consisting of immature connective tissue. Obliteration of the DV always started at this origin and proceeded toward the posterior vena cava. There was a considerable variation in the time of the closure of the DV. In most cases, however, the origin of the DV was obliterated within two weeks of birth.