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Using FEC as a monitoring tool

Are roundworms the problem?

    • Evidence-based treatment
      • establish whether roundworms are the cause of diarrhoea and ill-thrift
      • confirm the presence of adult roundworms
    • Testing could save the time and costs of worming sheep if roundworms are not the problem

    Pooled FEC


When to treat?

  • Regular pooled egg counts ~2-4 weeks apart
    • Frequent monitoring can provide an indication of which fields are more wormy
  • Highlights the optimal time for treatment
    • Can be useful to improve flock productivity
  • Correct timing = greatest benefit from wormer treatments

Pooled FEC

Which animals to treat?

  • Targeting individual animals or groups
  • Treating only those animals which need reduces excess chemical usage and costs

Pooled FEC
Individual FEC

Did the treatment work?

  • Only viable test to check if anthelmintic treatments are working
  • Avoid wasting money & labor on treatments which are ineffective
  • Wormer resistance is common – understand what works on your farm to treat effectively

Pooled or individual FEC

What egg counts CAN’T tell you…

  • Eggs may not be present in the faeces before clinical disease – for example Nematodirus where the immature worms cause the greatest disease
  • Other tools (e.g. weightgain) are better suited to monitoring productivity
  •  A single faecal egg count only provides a snapshot of what is happening…frequent testing is required to maximize benefit
  • Egg counts can’t tell you which types of worms are present. Some species produce more eggs per adult worm (e.g. Haemonchus; barber’s pole worm) which can complicate interpretation of results
  • Egg count results do not always reflect the number of adult worms in the sheep.
    • Different types of worms producing different numbers of eggs
    • Sheep’s immunity can impact the number of eggs in faeces and production impact e.g. around lambing in ewes (peri-parturient relaxation of immunity)
    • High egg counts don’t always mean low productivity. Some animals can maintain production despite harboring worms (resilience)