Lecture 7 Flashcards
In which species is the extracranial internal carotid artery absent?
Cat
Ruminants (large and small)
Identify the following vessels.
1 - Internal carotid artery
2 - Cerebral arterial circle
3 - Basilar artery
4 - Branch of vertebral artery
Which four vessels can contribute to the cerebral arterial cirlce?
Internal carotid artery
Vertebral artery (via basilar)
Occipital artery
External carotid artery
In addition to contributing to the cerebral arterial circle, branches off the basilar artery supply what?
Brain stem and cerebellum
In animals lacking an extracranial internal carotid artery, which artery is the major supplier to the cerebral arterial circle?
External carotid artery
What is the name of this structure?
Rete mirabile
Where is the rete mirabile located?
Inside the calvarium in the epidural space.
Branches of which artery contribute to the rete mirabile?
Maxillary artery
What is the function of the rete mirabile?
Because it is near a venous sinus, it functions in cooling the blood entering the brain.
One artery emerges from the rete mirabile to supply bood to the brain. Which artery is this?
Intracranial internal carotid artery.
True or False: Pigs have an extracranial internal carotid artery, so do not have a rete mirabile.
False.
Pigs have both an extracranial internal carotid artery and a rete mirabile.
In the horse, which two veins come together to form the external jugular vein?
Maxillary v.
Linguofacial v.
What percentage of horses possess an internal jugular vein?
10%
Which vein drains the abaxial muscles of the neck?
Deep cervical vein.
Do small ruminents possess an internal jugular vein?
No.
Which is the preferred vein for blood draws in pigs?
Cranial vena cava.
Which side of the neck is preferred for blood draws in pigs? Why?
Right side.
Left phrenic nerve more vulnerable in location.
Thoracic duct drains on left side (possible lymph contamination).
Thyroid gland shifted to the left and caudal.
Where does the tracheal lymph duct originate in the dog?
Medial retropharyngeal lymph node
Where does the tracheal lymph duct originate in the horse?
Cranial deep cervical lymph node
Where does the tracheal lymph duct originate in the cow?
Lateral retropharyngeal lymph node
What are the two lymph drainage routes from the head in the pig?
Tracheal duct from the medial retropharyngeal lymph node.
Alternate route from the dorsal superficial cervical lymph node.
What is the primary route of lymph drainage from the head in the pig?
Alternate route from the dorsal superficial cervical lymph node.
Which two nerves must be blocked to eliminate motor and sensory innervation to the face?
Facial
Trigeminal
A horse presents to you with an eyelid laceration. Which nerves to you block to repair the injury?
Supraorbital
Auriculopalpebral
Which salivary gland is largest in the ruminant?
Mandibular
Define “lymphocenter.”
A localized collection of lymphatic tissue. Can contain one or more lymph nodes.
Identify the lymphocenters labeled 1, 2, 5, and 6.
- Parotid lymphocenter (single lymph node in the bovine).
- Mandibular lymphocenter.
- Medial retropharyngeal lymphocenter.
- Lateral retropharyngeal lymphocenter.
Which lymphocenter is found immediately rostral to the parotid salivary gland?
Parotid lymphocenter.
What is unique about the lymphoid tissues of equines?
Diffuse. Lymph nodes have a glandular appearance, and should not be mistaken for salivary glands.
True or False: the mandibular salivary gland in the equine is located caudal to the angle of the mandible.
FALSE.
The equine mandibular lymph nodes are rostral to the angle of the mandible and are fused into a V shape, with the tip of the V located near the vascular notch.
