Haematology

Question 1

In which breed does bovine leukocyte adhesion deficiency occur?

Answer 1

Holstein. Mean prevalence 8.1%

Question 2

What is the mechanism of transmission of BLAD?

Answer 2

Autosomal recessive. 1 gene mutation at CD18.

Question 3

What is the lifespan of Equine RBCs?

Answer 3

140-150 days

Question 4

What is the lifespan of Bovine RBCs?

Answer 4

160 days

Question 5

What is the lifespan of Caprine RBCs?

Answer 5

125 days

Question 6

What is the lifespan of Camelid RBCs?

Answer 6

60 days

Question 7

6 physiological roles of iron

Answer 7

1. haemoglobin and myglobin formation
2. neurotransmitter and myelin production
3. collagen formation
4. immunee system functions
5. DNA/RNA synthesis
6. ennzymatic systems

Question 8

Total body distribution of iron

Answer 8

Haemoglobin 64%
Ferritin 15-30%
Myoglobin 4%
Transferrin 0.1%

Question 9

How many mg/ kg BW iron is normal

Answer 9

20-50

Question 10

What is the nnormal mg Fe/ ml blood?

Answer 10

1mg Fe/ 2ml blood

Question 11

What are th 3 iron pools in thee body?

Answer 11

1. Transport
2. Functional
3. Storage

Question 12

What makes up the transport pool of iron?

Answer 12

Iron bound to transferrin = <1% of TBI.

Question 13

What makes up the functional iron pool?

Answer 13

70% haemoglobin. 15-30% myoglobin and enzymes.

Question 14

What makes up the iron storage pool?

Answer 14

95% as ferritin in the hepatocytes to prevent ROS. 5% as haemosiderin in the cytoplasm of Kupffer cells

Question 15

Describe iron absorption

Answer 15

1. Food - noncompetitive absorption at apical surface of duodenal enterocytes.
2. Heme Fe via heme carrier protein 1 - degraded by heme oxygenate - Fe enters nonheme iron pool.
3. Nonheme Fe absorbed as Fe2+ via divalent metal transporter 1 (DMT1) (also for Mn, Cu, Co, Pb, Zn, Cd) with endosome.
4. Fe in enterocyte - stored as ferritin - export to plasma via ferroportin in basolateral surface with hephaestin helping

Question 16

What triggers hepcidin production?

Answer 16

Increased liver iron stores.
LPS & IL-6

Question 17

How does hepcidin affect iron absorption?

Answer 17

Ferroportin internalisation - no Fe exported from enterocyte to plasma.
DMT 1 blocked - no nonheme iron absorption from GIT.

Question 18

Describe iron transport and metabolism

Answer 18

Transferrin receptor 1 expressed on EC surface of all cells - binds diferric transferrin - conformation change - endoscope formation - Fe release.

Question 19

Factors causing increased TFR 1 expression?

Answer 19

erythroid precursors, activated lymph nodes, hepatocytes