Differential Count of WBC
Differential count of WBC involves determining the concentration of each type of leucocyte. There are 5 different types of leucocytes; neutrophil, eosinophil, basophil, monocyte, lymphocyte. Differential count of WBC is done by preparing a blood smear and staining slide with suitable stain and counting individual number of leucocyte.
Materials Required:
- Glass slide
- Stain; Giemsa stain, Leishman stain or Wright stain
- Microscope
- Hand counter
- Micropipette
- Uncoagulated blood sample
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Procedure:
- A drop of blood is placed on clean, grease free slide with help of pipette
- Blood is spreaded with another slide at 45° angle to make uniform smear.
- Glass slides are allowed to dry for some time after formation of smear
- Glass slides are then stained using any one of stain; Leishman stain, giemsa stain
- Staining are done by placing slide on staining rack. Blood smear is covered with Leishman stain for a minute.
- Equal quantity of buffer is added and mixed by blowing. This mixture is allowed to remain on slide for 10 minutes.
- It is then washed in running water. Slides are allowed to dry in air for some time and observed under microscope under 10X. then slides are examined under 100 x under oil immersion
- A corner area is choosen and cells are counted and recorded on hand counter. Cells are counted till 100 cells are observed and percentage of each leukocyte is determined.
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Differential leucocyte percentage in different animals
|
 |
Cattle |
Buffalo |
Horse |
Goat |
Sheep |
Pig |
Dog |
Cat |
|
Neutrophil |
29.10 |
28.70 |
62 |
40 |
41 |
39 |
62.80 |
44.82 |
|
Eosinophil |
9.87 |
2.90 |
4 |
2.50 |
5.10 |
4.50 |
2-14 |
2-11 |
|
Lymphocyte |
51.40 |
60.60 |
20 |
48 |
50 |
52 |
10-28 |
15-44 |
|
Monocyte |
8.32 |
7.80 |
8 |
2 |
3 |
3.30 |
3-9 |
0.5-0.7 |
|
Basophil |
0-1 |
0.00 |
2 |
1.60 |
0.03 |
1.20 |
0-2 |
0-0.05 |
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