Promoting Sustainable Control of Cattle Parasites

Things to do now

Always read the label and ask advice from a vet, vet pharmacist or SQP before deciding which product to use.

Things to do now

Always weigh cattle or use a weigh band to calculate the correct dose for each animal

Things to do now

Check meat and milk withdrawal periods for each product before administration

Things to do now

For advice on managing parasite infections in sheep visit www.scops.org.uk

What is COWS?

Control Of Worms Sustainably (COWS) is a voluntary initiative aiming to provide the best available, evidence-based information to the beef and dairy cattle industries in relation to the sustainable control of both internal and external parasites.

COWS funders

As a voluntary initiative, COWS is kindly funded by: AgriSearch, AHDB, AHDA, AHDB Beef & Lamb, AHDB Dairy, AMTRA, HCC, NFU, NOAH and QMS. COWS also works closely with SCOPS.

Latest News

AHDB Parasite control guide 2026

15th April 2026

AHDB has published its Parasite Control Guide for 2026. Order a printed copy from here This useful document, updated annually, lists all the anthelmintic products available to buy to use on cattle, including Group 1 Benzimidazoles, Group 2 Levamisoles, Group 3 Macrocyclic Lactones, combination products, flukicides and ectoparasiticides. Choosing the right product and getting the ... Continued

COWS and SCOPS warn grazing livestock may still be at risk of liver fluke this winter

6th February 2026

SCOPS and COWS experts recently reviewed laboratory test results, post mortems and feedback from farms, and while losses due to liver fluke continue to be low this season, they warn there is still time for a ‘sting in the tail’. ‘Even though many parts of the UK have had a recent cold snap, there could ... Continued

Warning from COWS & SCOPS - a too early treatment will not provide protection

21st November 2025

A recent review of reports from laboratories and field experiences by experts from the Sustainable Control of Parasites in Sheep (SCOPS) and the Control of Worms Sustainably (COWS) groups supports earlier forecasts that the liver fluke season will be late again in 2025/6. This underlines the importance of testing when deciding if farmers need to ... Continued

COWS Funders

COWS Terms of Reference

Things to do at turnout

Steps you should be taking now to protect your herd

Beef

Spring-born suckler calves that are still suckling are not likely to need any treatment for worms. Any larvae on the pasture will be consumed by their mothers which will be mostly immune
If possible, turn out first grazing season cattle, such as dairy x beef calves and autumn-born weaned suckled calves, onto low risk pasture, eg not grazed by cattle last year. If using pasture grazed by youngstock last year, consider carrying out faecal egg counts for gut and lung worms. Only treat when necessary, rather than relying on doses of wormer throughout the season
For second season calves, monitor liver and rumen fluke by faecal egg counting BEFORE turnout. If necessary, treat with an appropriate product to kill adult fluke. Speak to the vet or SQP/RAMA about which product to use
Where there is risk of lungworm infection, based on farm history, buying-in policy etc, consider vaccinating youngstock before turnout. For older stock, do a risk assessment with the vet

Dairy

If possible, turn out first grazing season calves such as replacement heifers, onto low risk pastures, eg pastures not grazed by cattle last year. If using pasture grazed by youngstock last year, consider carrying out faecal egg counts for gut and lung worms. Only treat when necessary, rather than relying on frequent doses of wormer throughout the season
Monitor liver and rumen fluke by faecal egg counting before turnout. If necessary, treat with an appropriate product to kill adult fluke. Speak to your vet or animal health advisor about which product to use
For second season heifers, monitor liver and rumen fluke infection by taking faecal egg counts BEFORE turnout. If necessary, treat with an appropriate product to kill adult liver fluke. Speak to the vet or SQP/RAMA about which product to use
Where there is risk of lungworm infection, based on farm history, buying-in policy etc, consider vaccinating youngstock before turnout. For older stock, do a risk assessment with the vet

Resources

Vet, academic or researcher?

Take a look in Resources for more detailed information on all topics.

COWS Members

AgriSearch
AHDA
AHDB
AMTRA
APHA
Bishopton Veterinary Group
BCVA/Rob Howe
Farm First Veterinary Services
HCC
Anuschka Marsman
Moredun
NFU
NOAH
Mark Pass
QMS
RUMA
SRUC
The Livestock Partnership
Bruce Thompson
UK Agritech Centre
University of Liverpool
VMD