How can drench-resistant worms be kept out of your property?
Keeping drench-resistant worms out of your property is part of sustainable worm control.
Assume that purchased goats (and sheep) are carrying worms with some degree of drench resistance to one or more drench groups. See Drench groups and actives.
- ‘Quarantine’ drench all goats (including bucks) new to the property.
- Discuss with your veterinarian which drench groups and how many can be used, their dose rates and withholding periods, including those drench groups not registered for use in goats, but which can be used with an off-label veterinarian’s prescription. The quarantine treatment should ideally consist of:
- Meat and fibre goats: four drench groups are recommended, preferably including one from the most recently available products.
- Dairy goats whose milk will be for human consumption: the number of registered drench actives is limited to two (fenbendazole and abamectin).
- Do not mix different drenches unless the label states you can or under veterinary advice, as different products may be incompatible. Otherwise, use drench products concurrently—up the race with one product, then up the race again with the next.
- Quarantine the goats after treatment.
- Hold the goats in quarantine in yards (small mobs) or a secure paddock (larger mobs) for 1–3 days (1 day if feed is green high quality, 3 if it is dry low quality) to allow worm eggs present at the time of drenching to pass out of the gut.
- Provide adequate feed and water.
- If feasible, keep this paddock free of sheep, goats or alpacas for at least 3 months in summer or 6 months in cooler months.
- After quarantine, release the goats onto a paddock that is likely to be contaminated with worm larvae due to grazing by other goats or sheep. This would include most paddocks that have been grazed by home bred goats or sheep for the last 3 months. This will ‘dilute’ (lower the proportion of) resistant worms surviving treatment with worm larvae already on your property.
- WormTest the imported goats 14 days after drenching for added confidence that treatment was successful.
- Get expert advice on up-to-date recommendations for quarantine treatments (especially if step 3 cannot be achieved). These will evolve as the drench resistance picture changes.