A passage with well-defined walls, especially a tubular structure for the passage of excretions or secretions. See also ductus.
- accessory pancreatic d. — the duct of the dorsal pancreatic primordium that opens on the minor duodenal papilla. Called also Santorini's duct or duct of Santorini.
- allantoic d. — see urachus.
- alveolar d. — one of the final branches of the bronchial tree consisting of a tube whose walls are composed of alveoli.
- bile d., biliary d. — the passages for the conveyance of bile in and from the liver. See also bile duct.
- cochlear d. — a spiral membranous tube in the bony canal of the cochlea divided into the scala tympani, scala vestibuli and spiral lamina.
- common bile d. — a duct formed by the union of the cystic and hepatic ducts. See also bile duct.
- cystic d. — the passage connecting the gallbladder neck and the bile duct.
- efferent d. — any duct that gives outlet to a glandular secretion.
- ejaculatory d. — the duct formed by union of the ductus deferens and the duct of the seminal vesicles, opening into the prostatic urethra on the colliculus seminalis. Found in the horse and ruminants.
- endolymphatic d. — a canal connecting the membranous labyrinth of the ear with the endolymphatic sac.
- epididymal d. — developed from the first part of the mesonephric duct.
- excretory d. — one through which the secretion is conveyed from a gland.
- d. of Gartner — see gartner's ducts.
- hepatic d. — the excretory duct of the liver, or one of its branches in the lobes of the liver. See also bile duct.
- incisive d. — one of a pair of ducts perforating the palate and which communicate between the mouth and the nasal cavity; they are thought to conduct chemicals for olfactory appraisal by the vomeronasal organ.
- intralobar d. — ducts within lobes which provide drainage for secretions of lobes of glands.
- intralobular d. — ducts found within lobules which provide drainage for secretions of lobules of glands.
- lacrimal d. — one of the excretory ducts of the lacrimal gland. See also lacrimal apparatus.
- lacrimonasal d. — nasolacrimal duct.
- lactiferous d. — ducts conveying the milk secreted by the lobes of the mammary gland to the lactiferous sinuses or to the teats.
- lobar d. — drains the secretions from the lobes of gland, connecting with the main excretory duct.
- lobular d. — drains the secretions of lobules of glands.
- lymphatic d. — larger lymph drainage vessels, e.g. thoracic duct.
- lymphatic d. (left) — thoracic duct.
- lymphatic d. (right) — a vessel draining lymph from the cranial right side of the body, receiving lymph from the right subclavian, jugular and mediastinal trunks when those vessels do not open independently into the right brachiocephalic vein.
- mammary d. — lactiferous ducts.
- mandibular d. — drainage duct of the mandibular salivary gland.
- mesonephric d. — see mesonephric duct.
- metanephric d. — the embryonic ureter.
- müllerian d. — see müllerian duct.
- nasal d. — the duct leading from the lacrimal sac, opening on the floor of the nasal vestibule. Called also nasolacrimal duct. See also
lacrimal apparatus . - nasolacrimal d. — see nasal duct (above).
- nasopalatine d. — see incisive duct (above).
- pancreatic d. — the main excretory duct of the pancreas, which usually opens with the bile duct on the major duodenal papilla; may be a single duct, or two ducts which join, or two independent ducts opening into opposite sides of the intestine. See also bile duct. Called also Wirsung's duct.
- papillary d's (kidney) — the straight excretory or collecting portions of the renal tubules, which descend through the renal medulla to a renal papilla or renal crest.
- papillary d. (teat) — see teat canal.
- paramesonephric d. — müllerian duct.
- parotid d. — the duct by which the parotid gland empties into the mouth vestibule opposite the upper molars. See also
parotid glands . - perilymphatic d. — see
aqueduct of cochlea . - pronephric d. — the early embryonic duct from the primitive kidney which leads into the mesonephric duct in the embryo's later stages.
- prostatic d's — minute ducts from the prostate, opening into or near the prostatic sinuses on the dorsal wall of the urethra.
- salivary d's — the ducts of the salivary glands.
- semicircular d's — the long ducts of the membranous labyrinth of the ear.
- sublingual d. — the excretory ducts of the sublingual salivary glands.
- submandibular d. — the duct that drains the submandibular gland and opens at the sublingual caruncle. Called also submaxillary duct.
- submaxillary d. — submandibular duct (above).
- tear d. — nasolacrimal duct.
- thoracic d. — a duct beginning in the cisterna chyli and emptying into the venous system at the junction of the left subclavian and left jugular veins. It acts as a channel for the collection of lymph from the portions of the body caudal to the diaphragm and from the left side of the body cranial to the diaphragm.
- thyroglossal d. — the transient, non-patent duct, from the thyroid gland to the floor of the pharynx which is the legacy of the development of the thyroid from the floor of the pharynx.
- vitelline d. — see
meckel's diverticulum.
