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The observations of the anatomical closure of the ductus venosus (DV) and vestige of DV were studied in 22 cattle, raging from 210-day-old fetus to 3-years old Korean native cattle. Vinylite solution was injected into the hepatic, portal, umbilical veins and caudal vena cavae of 22 specimens for vinylite corrosion casts. The DV originated at the confluence of the umbilical and portal veins and emptied into the left hepatic vein or posterior vena cava. The DVs were persisted in a 210-day-old fetus, a 240-day-old fetus, and a 270-day-old fetus. Two newborns, two 2-year-old and two 3-year-old cattle had no rudimentum of DV (6 vases, 31.58%). However, vestiges of DV in varying sizes were observed in a 14-day-old, a 30-day-old, two 180-day-old and nine adult cattle (13 cases, 68.42%). The lengths of vestiges of DV were about 4.97~99.66 mm. Therefore, the present study demonstrates that DV in cattle can be degenerated during the late period of a pregnancy.
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