Lymphatic system

Question 1

What is the function of the lymphatic system?

Answer 1

drains fluids from tissue space and transports fats from the gut to the blood.
It also has a supervisory role in host defense.

Question 2

Where are lymph vessels absent?

Answer 2

lens, cornea and hyaline cartilage.

Question 3

What are lymphocenters?

Answer 3

these are groups of lymph nodes whci drain into the same region of the body in all species

Question 4

What are the lymphocenters of the head?

Answer 4

• parotid lymph node (palpable in dogs and ox).
• mandibular lymph nodes (palpable in dogs, ox and horse).
• lateral pharyngeal lymph (absent in dog but if present palpable and palpable in ox).
• superficial cervical lymph nodes (palpable in horse, ox and dog).
• axillary lymph nodes (dog)
• cubital lymph node (horse)
• superficial popliteal lymph (dog)
• subiliac lymph nodes (ruminants and horse)
• superficial inguinal inn (dog, ruminant and horse)

Question 5

Where are the parotid lymph nodes?

Answer 5

under cranial edge of parotid glands.

Question 6

Where are the mandibular lymph nodes located?

Answer 6

they’re a group located ventral to the angle of the jaw.

Question 7

Where is the lateral retropharyngeal lymph node located?

Answer 7

around the neck region.

Question 8

Where are the superficial cervical lymph nodes located?

Answer 8

located in the shoulder joint under superficial neck muscles.

Question 9

Where is the axillary lymph node located?

Answer 9

located in the axilla

Question 10

Where is the superficial popliteal lymph node located?

Answer 10

the superficial popliteal is only in carnivores and in other species deep popliteal lymph nodes.

Question 11

What is the movement of lymph direction?

Answer 11

it flows from abdominal (high pressure) to thoracic (low pressure).

Question 12

What are the two main trunks?

Answer 12

thoracic duct and great lymphatic duct.

Question 13

What are the lymphoid tissues?

Answer 13

• diffuse lymphoid tissues
• follicles or lymphoid nodules (oval masses of lymphoid tissue in digestive, respiratory and urinary tract)
• the lymph nodes (lymph tissue wrapped in connective tissue).

Question 14

What are the structures of lymph nodes?

Answer 14

they are usually round but they can be elongated. They range from grayish white to reddish brown and black.

Question 15

What are the thoracic duct characteristics?

Answer 15

it drains lymph from the body except the right forelimb, right side of head, neck and thorax.

Question 16

Where is the thoracic duct located?

Answer 16

it begins next to lumbar vertebrae (cysterna chyli). it has lumbar trunks which collect hindlimb and pelvis lymph and visceral which collects from celiac and intestinal trunks.

Question 17

Where is the great lymphatic duct located?

Answer 17

at thorax entrance and ends at jugular vein confluence.

it drains the right forelimb and the right sides of the head, neck and the thorax.

Question 18

What are the forelimb lymph nodes?

Answer 18

• axillary lymph

- cubital lymph

Question 19

What are the two branches of the thorax in the horse?

Answer 19

parietal and visceral

Question 20

What are the nodes of the visceral branch?

Answer 20

• cranial, middle and caudal mediastinal lymph nodes
• tracheobronchial lymph
• lung lymph nodes

Question 21

Ruminants and horses posses both deep popliteal and superficial popliteal lymph nodes. True or False?

Answer 21

false, they only have deep popliteal lymph nodes.

Question 22

What are the lymph nodes of the forelimb in the cow?

Answer 22

axillary and accessory axillary lymph node.

Question 23

What are the hindlimb lymph nodes of the cow?

Answer 23

• popliteal lymph nodes
• subiliac lymph nodes
• superficial inguinal lymph nodes
• ischial lymph nodes

Question 24

Which head lymph node is sometimes absent in the dog?

Answer 24

the lateral retropharyngeal lymph nodes.