Fig. 1

Schematic view (a) and photograph (b) of the thoracic duct and the tracheal trunk in the cervicothoracic region on the left side. (a) The thoracic duct containing lymph draining the lungs emerging from the thoracic cavity joins the external jugular vein at the cranial thoracic inlet. The ampulla of the thoracic duct is located craniomedially to the first rib (l). The thoracic duct (k) is medial to the subclavian and superficial cervical arteries (c & d respectively) and lateral to the common carotid artery (g) and vagosympathetic trunk (i). (a) thoracic aorta; (b) cranial vena cava; (c) subclavian artery; (d) superficial cervical artery; (e) external jugular vein; (f) axillary artery; (g) common carotid artery; (h) heart; (i) vagosympathetic trunk; (j) tracheal trunk; (k) thoracic duct; (l) first rib; (m) longus colli; (n) brachiocephalic trunk; (o) oesophagus; (p) pulmonary trunk. (b) Dissections were performed from the cranial border of the left forelimb to expose the cranial thoracic inlet. The superficial cervical artery (d) was retracted to reveal the thoracic duct (k) and its point of entry into the left external jugular vein (e). The tracheal trunk (j) coursing caudally from the medial retropharyngeal lymph centre also entered the left external jugular vein (e). The image was taken from a euthanized 7-week old Large White pig