Australian sheep producers spend an estimated $93 million per year on sheep drenches and knowing that they are working can provide peace of mind for many wool producers.
Australian Wool Innovation General Manager for Research Dr Jane Littlejohn highlighted that most of the time, producers may not definitively know if the drench is working because drench testing is often not feasible.
“One of the reasons why woolgrowers do not drench test is because the traditional test is based on low-sensitivity counts that require a mob average faecal egg count (FEC) of 300 before it can begin,” Dr Littlejohn explained.
“This may be hard to achieve, especially if the sheep are being managed for low worm burdens. The second problem is leaving sheep until they have higher worm burdens a this exposes them to the risk of sickness and low production.”
AWI’s research project has been designed to validate a new test method based on improved technologies for counting and analysis of FECs.
Dr Littlejohn shared, “the result should be a test that is simple and cheap to conduct but provides diagnostic answers that are more robust and reliable.”
“This includes only minor changes to the way the test is set-up on farm. Possibly the most important change is the dropping of the untreated control group for future testing.
“This will also reduce the risk of seriously ill animals due to high parasite burdens, particularly in areas where barbers pole worms have become the major problem.”
To achieve this, sheep producers across Australia are being encouraged to collect dung samples from a mob of wormy sheep on the day of drenching, then again 14 days after the drench.
The samples are sent to the lab and subjected to a four-way analysis that includes:
- Traditional worm egg count, with an un-drenched control group for comparison
- Traditional worm egg count, but the ‘before’ samples are used instead of an un-drenched control group.
- Mini-FLOTAC worm egg count (higher sensitivity), with an un-drenched control comparison group.
- Mini-FLOTAC, using the ‘before’ samples as control group.
Comparing the performance of the four different methods is the key part of this study.
Dawbuts veterinary parasitologist Dr. Janina McKay-Demeler, who has international experience in worm research, outlined she has set up the trial to clearly show the strengths and weaknesses of the various approaches to drench testing.
“We have trialled the Mini-FLOTAC for drench testing in European sheep and the results are impressive. It’s a bit like using the latest mobile phone technology compared to the old landline dial phones,” Dr McKay-Demeler said.
“In the world of electronics everyone wants to keep up with the newest technology available, while it is surprisingly still difficult to convince people to use newer and much more sophisticated methods in drench testing.