Faecal Worm Egg Counts – Why and When.
Worm Egg Counts are a very useful tool. WECs conducted at strategic times will be helpful for a number of reasons:
1. Prevent unnecessary drenching saving both time & money
2. Reduce the development of drench resistance
3. Reduce the worm burden on the pasture
4. Increase productivity by recognising sub-clinical disease
5. Reduce the risk of a worm outbreak resulting in sheep losses
6. Give an indication of the effectiveness of a drench

The WEC is a simple test. It involves the producer collecting 10- 20 individual faecal samples from a mob of sheep. From these samples we can determine a mob WEC average. Based on the time of year, class of sheep, weather conditions & condition of the sheep, a decision to drench or not is made.

WEC should be conducted at the following times:
1. Pre-lambing
2. Pre-marking (ewes)
3. Pre-weaning
4. Pre first summer drench. Weaners and hoggets should be drenched at the start of summer. Older sheep should be monitored to see if this is required.
5. Autumn before the break of the season. If a drench is required this will reduce contamination of winter pastures. Lambing ewes that did not receive a summer drench should be drenched by early April.
6. Any time that sheep are scouring or not performing as well as expected.