Knowledge Based Strategies for Roundworm Control

Moredun-logoSummary written by Frank Jackson BSc, PhD, David Bartley BSc, PhD and Neil Sargison BA Vet MB, DSHP, FRCVS

Taken from Moredun Foundation Newsheet Volume 4 No. 15



  • internal-parasites-2-drenching-ewePlan a strategic worming programme with your veterinary practitioner that will reduce unnecessary treatment. Where possible avoid frequent drenching with anthelmintic by integration with grazing management to provide some 'low-risk' pastures.
  • Use parasitological and performance monitoring to gather data which will enable you to set performance targets for your lambs.
  • Undertake a post drench efficacy check to determine whether the class of anthelmintic/wormer is still effective or whether drug resistance is present.
  • Treat bought-in stock and animals that have been grazed off farm with drenches from both the 20LV and 3-ML class of drugs and where possible yard for at least 24-48 hours prior to turnout.
  • Turn out quarantine treated stock onto dirty pastures to ensure that any resistant survivors form only a minor proportion of the total population.
  • Do not underdose stock by underestimating liveweight. Weigh a small number of representative animals and base the dosing volume on the heaviest animal in the group.
  • Accurately calculate the correct dose volume and check that the dosing gun is delivering the correct volume of drench prior to use. Administer all drenches over the back of the tongue.



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