yolk stalk

stalk (stawk) an elongated anatomical structure resembling the stem of a plant.

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allantoic stalk  the slender tube interposed between the urogenital sinus and allantoic sac; it is the precursor of the urachus.

body stalk , connecting stalk a bridge of mesoderm connecting the caudal end of the young embryo with the trophoblastic tissues; the precursor of part of the umbilical cord.

pineal stalk  habenula (2).

yolk stalk  a narrow duct connecting the yolk sac (umbilical vesicle) with the midgut of the early embryo.

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yolk stalk

n.

A narrow ductlike part that connects the yolk sac to the middle of the digestive tract of an embryo. Also called omphalomesenteric duct.

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yolk stalk,

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.

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yolk

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.

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yolk sacculitis

see avian omphalitis.

yolk stalk

the connection, passing through the umbilicus, between the yolk sac and the fetus.

yolk stain

a stain of wool originating from the yolk.