Complicated cases are common, and in all alike the umbilical veins usually remain open and can be explored by a probe passed at first upward and then forward toward the liver.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler
In other cases the umbilical veins become involved, in which case the swelling extends forward as well as backward.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler
7. Armatage's iron clamp for umbilical or navel hernia.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler