Tips of the Trade: Worm Egg (WEC) Sampling
It is great to see more Ram Breeders measuring fecal worm egg count (WEC) from individual sheep to generate WEC ASBVs (Australian Sheep Breeding Values).
Here are some tips that we find helpful when collecting samples that could help minimise mistakes and extra costs:
Avoid Typos and Duplicates by using your eID tag to print a sticky label barcode. Many breeder are still writing the tag number on a jar or plastic gag, this is often more time consuming and the % of errors can increase. Make the most of your eID tags by connecting the sticky label printer to your stick reader, in most cases you will print the eID tag number, however some stick readers have the capability to print a barcode with the visual tag as well.
We use zip lock bags (sandwich or snack size), make sure you check with your testing lab as some labs prefer jars. The sticky barcodes can be stuck to the front of the bags/jar and the sample placed inside. The sticky label should be able to handle moisture on them.
Make sure the mob you are testing has an average of 300epg. This is really important as we don't want a high percentage of zero counts (we need variation in the data for it to be meaningful). We recommend a monitor WEC test of a random 10 samples, reported back so you can see the variation in the mob, not just an averaged of the 10 samples.
Faecal Consistency (FC) and DAG are also good traits to capture at the same time as WEC sampling.
Book your samples in before collecting. Let your testing facility know that you will be taking samples and how many to expect. This will help with turn around time.
The average cost of a sticky label barcode printer is $1,470 incl GST (there may be others on the market, please check they will be suited for what you need). In a recent example, a producer had collected over 800 WEC samples, where the VIDs were written on the jar, there ended up being 44 duplicate sample IDs, and the data for these animals was discarded from the analysis. At an average of $6.60/sample, that's a $290 mistake that could have been avoided. To retest these animals, you would need to wait for another worm burden and test the whole mob (cohort) again to be in line with good data quality protocols.
If you follow the Sheep Genetics quality assurance guidelines and you can measure WEC at weaning, post weaning, yearling and hogget stages, giving 4 opportunities in a Sheep's lifetime.
Watch the video below for a demonstration!