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Study published on current uptake of best practice principles of worm control on British farms

New study by the Moredun Research Institute examines how livestock farmers procure anti-helmintic drugs for their animals and identifies gaps in advice provision.

Sheep in a pack
Many sheep are at risk of helminth infection from grazing

Helminths are important, common parasites of livestock worldwide. These worms have been controlled for many years by the regular use of broad spectrum anthelmintics; however, drug resistance is now a major issue, especially in worms of small ruminants.

Anthelmintic resistance is a major threat to global food security as new anthelmintic products do not appear to be coming to market in the short to medium term.

Because of the increasing prevalence of drug resistant parasites, more sustainable approaches to worm control need to be deployed on farms to protect anthelmintic efficacy.

Best practice

These approaches are termed ‘best practice’.  They include the appropriate application of dewormers and the use of evidence-based protocols involving diagnostics, to inform the need for anthelmintic treatments, alongside management practices designed to break the transmission cycle of the worms.  

However there is no published information on how farmer/prescriber interactions at the point of anthelmintic purchase shape the application of best practice worm control principles on-farm.

Large scale online survey of UK farmers

To find out about how the experiences of UK ruminant farmers  relate to anthelmintic purchasing and the provision of best practice advice at the point-of-sale, the Matthews’ group undertook a large online survey.

This survey explored farmer experiences in purchasing anthelmintics from the three UK animal medicines’ prescribers (veterinarians, Suitably Qualified Persons [SQPs] and veterinary pharmacists) and investigated farmer attitudes to anthelmintic use and drug resistance in worms.

Value of face-to-face purchasing

When grouped according to the route through which they purchased anthelmintics, those farmers who bought in face-to-face interactions were significantly more likely to state that they valued their prescriber’s knowledge of parasites/anthelmintics than those farmers that purchased anthelmintics via the telephone or internet. 

Farmers that purchased online were significantly less likely to consider prescriber advice.

The study also examined how frequently different livestock farmers carried out testing for helminth infection and resistance to dewormers. 

Generally, sheep farmers undertook FEC testing more than the cattle farmer respondents, but relatively few farmers stated they ever conducted anthelmintic sensitivity testing, with the majority of cattle farmers never having tested for dewormer efficacy.  This was despite a high level of concern for anthelmintic resistance stated by all types of farmers.  


The results from this study suggest that UK farmers that bought anthelmintics from veterinarians were more likely to be exposed to diagnostic-led worm control advice, as currently recommended in the industry guidelines. 

Gaps in advice provision, particularly in relation to efficacy testing, have been identified in all farmer groups and these gaps now need to be addressed in training courses for all types of prescribers.

A workshop was recently held at the UK’s Veterinary Medicines Directorate, the government agency responsible for the approval and regulation of animal medicines, in which the results of this survey were shared and discussed with the major stakeholder groups in the ruminant livestock industry.

The results will be published in the July 2018 issue of Preventive Veterinary Medicine (Easton S, Pinchbeck GL, Bartley DJ, Hodgkinson JE, Matthews JB. 2018. A survey of experiences of UK cattle and sheep farmers with anthelmintic prescribers; Are best practice principles being deployed at farm level? Prev. Vet. Med. 155: 27-37).

Read the paper on Science Direct