Worm Egg Count




McMaster slide this provides a simple counting chamber

Make flotation solution

Super saturated sugar solution:

200 ml water

Heat to boiling

Add sugar, until no more will dissolve

Pour off the sugar solution into a glass container. This will keep

Zinc Sulphate solution: as above but with ZnSO4

100 ml bottle with top and small glass beads to assist mixing

Fresh faeces



Mix 2g of fresh faeces with 58 ml of floatation solution or:

Mix 2g of fresh faeces with 2.5 ml of 0.1% methylene blue solution (aids visualisation) and 55.5 ml of floatation solution

Allow the mixture to settle for 5 minutes

Using a pipette place 0.3 ml of mixture into each of the 3 chambers in the McMaster slide

View down the microscope and count the number of worm eggs in each chamber

Using the 0.3 ml McMaster slide the number of eggs per gram is the number visible x 100

Volume of sample (faeces + 0.1% methylene blue) + volume of flotation solution

Volume of sample x volume per chamber


[2 + 58 (or 2.5+55)] Divided by (2*0.3) = epg*100

In this example volume = weight ie 1 ml = 1 g

The zinc sulphate salt solution is used for Ascaris suum eggs, which do not float in saturated sugar solutions

Example of pig worm egg count results not to scale coccidian are small

Worms strongyle eggs copy

Worm Trichuris egg copy1


Strongyle egg cannot distinguish species

Trichuris suis egg

Strongyloides ransomi has a larvae inside the egg - piglet






Isospora suis

Metastrongylus eggs

(note larva in egg)

Ascaris suum egg

Coccidiosis (much smaller than worm eggs) Isospora suis


Size comparison of the common pig parasite eggs

Pig Parasites General




The major sites where the parasites of the pig can be found

Anat pig parasites