Blood Sample Collection for vWD and Haemophilia A

Please read the entire instructions before commencing sampling procedure.


Animal Requirements

  1. The animal should be fasted for 12 hours before sample collection.
  2. A resting sample should be collected.
  3. Excitement must be minimised; if sedation is needed, Xylazine at a maximal dose of 2 mg/kg is recommended.
  4. Avoid collecting samples from bitches which are in heat, pregnant or lactating as these variables may alter the vWF levels.
  5. Avoid collecting samples from sick animals as vWF may increase in response to stress, acute haemorrhage, inflammation and infection.

Sample Requirements

  1. Sodium citrate is the required anticoagulant. The tube must be filled to the mark on the tube for the correct ratio of 1 part citrate to 9 parts blood. Do not overfill or underfill.
  2. Collect the sample by "clean" venipuncture. If there are problems with the collection, it is better to collect a fresh sample.
  3. The minimum sample volume needed for either vWF or Factor VIII is 2 ml of anticoagulated blood. The sodium citrate tubes supplied by VETPATH take 2 ml of blood. It is recommended that you collect two tubes if possible.

Sample Submission

NOTE: Plasma is preferable to blood and it is recommended that the sample be centrifuged as soon as possible.

If you have a centrifuge

  1. Centrifuge to separate the cells from the plasma.
  2. Transfer the plasma to two plain plastic tubes using plastic pipettes. Do not use glass tubes or pipettes. Do not use clot activator tubes.
  3. Ensure that the tubes are labelled with the animal's name, owner's name and the fact that the tubes are citrated plasma.
  4. The plasma should be kept cool; ie 4oC after collection and in transit to VETPATH.
  5. If the plasma cannot be transported to VETPATH within 24 hours of collection, the plasma samples should be frozen. It is essential that the samples remain frozen during transport to VETPATH; they must not be allowed to thaw in transit.

If you don't have a centrifuge

If you do NOT have a centrifuge: VETPATH has a centrifuge that can be lent to Metropolitan clinics with appropriate notice. If this is not possible, follow the steps below:

  1. Wrap the whole citrated blood sample in cotton wool or newspaper and place in an esky with ice packs. The sample must not rest directly on icepacks as this will cause haemolysis.
  2. Transport the cool citrated blood sample to VETPATH.
  3. The sample must reach VETPATH within 24 hours of collection.

DCI-03 vWF and Factor VIII (V2.0, 18-03-2003)

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