Taking a dung sample for a worm egg count

Getting as accurate a result as possible from your test begins with collecting the dung sample. Redworm and roundworm eggs, which are the parasites we are predominantly looking for when we carry out a worm egg count, are distributed fairly evenly through the faeces. This is what makes a worm count a very good test for detecting adult, egg laying infections of these worms.

Watch our video on how to take a sample for a worm egg count here:

Choose a day to collect samples when worming is due or overdue for most of the horses. This is important so that you don’t get a false result caused by wormer still working in your horse – unless you are carrying out a resistance test specifically to measure drug efficacy. The dung should be as fresh as possible but can still be posted the day after collection.

  1. Use the glove to pick up about five small pinches from different places across a fresh dung pile.
  2. Press the dung into the sample container, filling it to the top to exclude air. This is important to ensure we have sufficient dung for a representative test.
  3. Label the sample with the horse’s name and number it if you are sending more than one sample in the envelope. Please write in ball point pen as water based inks may wash off.
  4. Put the container in the plastic bag. Do not put any paperwork in with it.
  5. Put sample, paperwork and payment or voucher into the postpaid return bag. Pop in the post box.

 We'll carry out the requested lab test to generate your result - usually the industry standard ‘Modified McMaster technique’ for worm egg counts. Samples are viable for around six days. If they are delayed in the post or there is insufficient faecal material to do the test we’ll contact you and ask you to collect the sample again.

 All samples are tested twice and the result averaged between the two. We test samples on the day they are received in the lab with results returned to you on the same day.

 > Read about our Modified McMaster test process here

 Liver fluke tests are conducted the same way as a standard worm egg count, using a different solution to float off the relatively heavier eggs of this parasite. Because of the challenge the liver fluke has in reproducing in the horse we will ask you to take three dung samples on consecutive days, refrigerating the first two and sending all of them for testing on the third day as per protocol advised by University of Glasgow School of Veterinary Medicine.

Lungworm tests are conducted using a sedimentation test to separate out the lungworm larvae. Please send two full sample pots of dung when requesting this test.