Sheep Worming Programs

For those of you who have not yet invested in a Farm Health Plan here are some basic rules following the SCOPS report. SCOOPS stands for the Sustainable Control of Parasites in Sheep.

1. Develop a strategy for the year.

  • Always plan the year ahead ideally using a veterinary health plan.
  • Develop a strategy that is specific for your farming enterprise.

2. Reduce dependency on wormers.

  • Focus efforts on grazing management.
  • Reduce the risk of importing resistant worms onto the farm.
  • Select rams to enhance the genetic resistance to worms within the flock.

3. Test for wormer resistance.

  • Find out if worms on your farm are fully susceptible to the class of wormer you are using by having laboratory tests done on faeces collected from at least 10 treated lambs.
  • Techniques used to assess wormer resistance:
  1. Post dosing faecal egg counts.
  2. Faecal egg count reduction tests.
  3. Larval development tests.
  • Larval development tests are usually more accurate but the two simpler tests may well be sufficient on your farm.

4. Only worm when necessary.

  • Follow your health plan.
  • Dose ewes and rams in poor condition.
  • Pre-lambing dose all ewes.

5. Always use quarantine dosing.

  • Quarantine dosing is essential to prevent buying-in resistant worms onto your farm.
  • Treat all bought-in sheep immediately with an Ivomectin injection plus Levitape – administer sequentially – use the normal dose rate – do not mix the wormers or use the same gun.
  • Hold the treated sheep in the ‘sacrifice area’ (an area on your farm not used by any other grazing sheep) for one or two days.
  • After this holding period, release new sheep onto a pasture that is likely to be contaminated by worms from the home flock.

6. Maintain the population of susceptible, treatable worms.

  • To preserve susceptible worms and reduce the development of resistance:
  • Delay moving sheep after worming.
  • Worm and turn out to the same pasture; move to a clean pasture a week later.
  • Alternatively, if practicably possible and after veterinary advice, leave a percentage of the group of sheep untreated (usually those in best condition and low faecal egg count).

7. Select an appropriate wormer.

  • Wherever possible rotate between the three groups of wormer (White drenches, Levamisole and Avermectins).
  • Try to us the most appropriate wormer for the time of year and purpose of treatment.
  • Try to use a narrow spectrum product whenever possible.

8. Ensure the correct dosage.

  • Check the accuracy of the worming gun using a suitable measuring vessel.
  • Dose accurately and according to the heaviest sheep in the group but avoid exceeding the recommended dosing band.
  • The use of weighing scales is a good idea and you may find that your stock weighs more than you think, due to improved genetics, nutrition and health practices.

9. Administer effectively.

  • Follow the guidance as indicated on the produce date sheet.
  • Use suitable drenching equipment, ensuring best dosing technique.

10. Further information [ link ]