Parasite-control guide updated

21 Jan 2020

The Control of Worms Sustainably in cattle group (COWS) has released updated chapters of its technical guide to parasite control.

The additional sections – covering round worms, lungworm, liver and rumen fluke and ectoparasites such as flies, lice and ticks – provide a sound basis for advice for producers and their advisers.

Research groups

The guide was originally written more than 20 years ago and previously revised in 2014. The new chapters, updated by research groups from universities across the UK, can be viewed on the COWS website at

Each updated chapter includes life cycles, clinical signs, high risk conditions, diagnosis, testing, treatment, control and quarantine.

Resistance concern

One of the biggest changes to the content has been where resistance is concerned.

“We know a lot more about liver fluke resistance to products containing triclabendazole than we did five years ago,” says University of Liverpool’s Diana Williams.

Control programme

“Triclabendazole resistance has now been reported in cattle in the UK, so it is vital that the resistance status is established for each farm before a control programme is developed.

She adds that a faecal egg count reduction test (FECRT) can be used, particularly where there are also sheep. “If there is resistance, a plan using alternative products must be drawn up.”

Rumen fluke

The section on rumen fluke is also more comprehensive than when the original COWS Guide was written.

“Rumen fluke have been found increasingly in British cattle during the past five years, and DNA analysis has found the species involved is new to the UK,” explains Professor Williams. “Recent research suggest this species uses the same mud snail for its intermediate host as that used by liver fluke.”

Health plans

The newly edited chapters also encourage producers to include parasite control in their herd health plans.

“We want producers to take a strategic approach to parasite control,” says Professor Williams. “Having a plan minimises the risk of infections and prevents ‘fire-brigade’ treatments, when vets have to be called in to treat sick animals.”