Blood transfusions in cattle

Question 1

What conditions indicate a blood transfusion?

Answer 1

• Post-partum rupture of the uterine artery
• Poor haemostasis after dehorning or castration
• Laceration of superficial blood vessels (udder/milk vein)
• Abomasal ulceration (bleeding)
• Failure of passive transfer of immunoglobulins in neonate

Question 2

How many blood groups are there in cattle? Is this an issue for transfusion?

Answer 2

• 11 groups
• most individuals do not have antibodies against other blood group antigens unless sensitised by previous transfusion.

Question 3

What is the anticoagulant of choice? How much is needed?

Answer 3

Sodium citrate
1 part sodium:9 part blood

Question 4

What clinical signs are indicative a transfusion may be needed?

Answer 4

• tachycardia (>100bpm)
• tachypneoa
• cool extremities
• PCV <15%

Question 5

How can you select a blood donor?

Answer 5

• Temperament: donor needs to be easily handled
  and restrained during collection
  ● General health: prevent transfer or exacerbation of
  disease in donor or recipient
  ● Pregnancy: donation may place unacceptable
  demands on mid- to late-term fetus
  ● Conformation/condition score: heavily-muscled or
  fat animals make jugular access more difficult
  ● Body weight: available blood volume is related to
  body weight (7-8%), so adult animals of large breeds
  can supply sufficient blood for most indications.

Question 6

What proportion of a cow’s weight does its total blood volume represent?

Answer 6

7-8%

Question 7

How much blood can you collect?

Answer 7

25% of total blood volume max
Usually do 10-15%

Question 8

What are the signs of incompatibility in the recipient?

Answer 8

• urticaria
• tachypnoea
• tahycardia