Determination of packed cell volume by wintrobe hematocrite tube

 

Packed cell volume (PCV) by wintrobe hematocrite tube

The hematocrite or PCV is the volume of erythrocytes expressed as percentage of the volume of whole blood. The hematocrite is estimated by centrifugation of anticoagulated whole blood. Erythrocytes are packed toward the bottom of the tube by the centrifugal force. Hematocrite represents the concentration of erythrocyte in the blood.

 

Required material

• Ø  Wintrobe hematocrite tube
• Ø  Special loading pipette
• Ø  Centrifuge machine
• Ø  Blood sample
• Ø  Cotton

 

Procedure

• Take anticogulated well mixed blood into the special loading pipette.
• Place the tip of the special loading pipette in bottom of the hematocrite tube.
• Expel the blood slowly by pressing the rubber bulb of pipette and draw up the pipette and fill the blood up to10 or 0 mark.
• Wipe out the blood above the 10 mark with cotton.
• Place the tube in centrifuge machine and centrifuge at 3000 rpm for 30 minute.
• After centrifuge take the tube from centrifuge and take reading from bottom of the scale.
• The result is expressed in percentage by using the formula:
• Pcv = Height of red cell (cm)* 100 /  Height of whole blood

SPECIES	RANGE (%)
Cattle	35
Sheep	38
Goat	45
Dog	45
Cat	37
Horse	42
Pig	42
Chicken	35