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the narrowed connection between the intraembryonic gut and the yolk sac; its walls are splanchnopleure.
A narrow ductlike part that connects the yolk sac to the middle of the digestive tract of an embryo.
the narrow duct connecting the yolk sac with the midgut of the embryo during the early stages of prenatal development. It connects at the region of the future ileum and usually undergoes complete obliteration but occasionally may appear as a diverticulum. Also called omphalomesenteric duct, umbilical duct, vitelline duct. See also Meckel's diverticulum.
om·pha·lo·en·ter·ic duct(om'fă-lō-en-ter'ik dŭkt)
1. the stored nutrient of the ovum; it is also rich in antibody which is absorbed into the circulation of the embryo in the last third of incubation and is the mechanism by which maternal antibody is transferred to the young bird. See also yolk sac, egg.
2. the combined secretion of the sebaceous and sudoriferous glands of the sheep's skin and extractable from the fleece.
see avian omphalitis.
the connection, passing through the umbilicus, between the yolk sac and the fetus.
a stain of wool originating from the yolk.