STAR DIGITAL CONTENT
Modified McMaster technique to count worm eggs
1. Assemble the required equipment:
• Personal protective equipment( PPE): gloves and apron / laboratory coat
• Beaker, stirrer, small sieve, test tubes( s), bowl, saturated salt solution, Pasteur pipette, McMaster chamber.
2. Put on the PPE. 3. Place 3 g of faeces in the beaker.
4. Add 42 ml of water to the beaker and, ideally, use a mechanical stirrer to mix the contents.
5. Pour the mixture through a small sieve over a separate bowl.
6. Discard the debris as hazardous waste.
7. Add 15 ml of the filtrate to a test tube and centrifuge at 1,000 – 1,500 rpm for 5 min.
8. Remove and discard the supernatant, leaving only the sediment.
9. Add 2 – 3 ml of saturated salt solution to the sediment and mix. Once the sediment is resuspended, add more saturated salt solution to make 15 ml in total.
10. Remove 0.15 ml of the solution with a Pasteur pipette and fill one side of the McMaster chamber.
11. Remove 0.15 ml of the solution with a Pasteur pipette and fill the other side of the McMaster chamber.
12. Examine each side of the McMaster slide under × 40 magnification, checking each section of the grid and counting any eggs present.
13. Calculate the number of eggs per gram of faeces by multiplying the total number of eggs counted by 50.
Baermann technique to count parasite larvae
Note: the sample will need to be left in warm water overnight, which requires a safe place to do so.
1. Assemble the required equipment:
• Personal protective equipment( PPE): gloves and apron / laboratory coat
• Baermann equipment: funnel, metal clamp stand, short piece of rubber tubing and a clip
• Gauze / muslin( about twice the size of the rim of the funnel), centrifuge tube, microscope slides, glass coverslips, Lugol ' s iodine.
2. Put on the PPE.
3. Attach the rubber tubing to the end of the funnel and seal the end of the tubing with the clip.
4. Clamp the funnel on to the metal clamp stand.
5. Fill the funnel to around 1 cm below the rim with warm water and place the gauze / muslin on top of the funnel.
6. Place 5 – 15 g of faeces on to the gauze / muslin, ensuring it is covered with the water.
7. Allow to stand overnight.
8. In the morning, place a centrifuge tube under the rubber tubing and unclip the clamp from the bottom to allow the tube to fill with liquid.
9. Centrifuge the tube at 1,500 rpm for 1 min.
10. Remove and discard the supernatant. Pipette the remaining sediment on to a microscope slide.
11. Add one drop of Lugol ' s iodine to the sample and examine under × 40 and × 100 magnification.
12. Record the findings.
14. Record the findings.
Appendix 1( to page 29 of VNJ). Modified McMaster technique and Baermann technique.
Veterinary Nursing Journal | Volume 41( 2) • April 2026 | EXCLUSIVE DIGITAL CONTENT
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