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)