Statement from SCOPS and COWS on parasite treatments and the environment

22nd June 2021

The Sustainable Control of Parasites in Sheep (SCOPS) and Control of Worms Sustainably (COWS) principles are based on the responsible use of medicines such as anthelmintics, flukicides and ectoparasiticides. Our aim is to ensure these products are only used when necessary and ideally supported by a diagnosis or a risk assessment that confirms the need to protect animals from a genuine risk of disease. This approach avoids the unnecessary use of medicines and hence minimises the risks medicines pose to the environment.

SCOPS and COWS are aware of increasing interest in and the promotion of the biodiversity benefits of grazing livestock, including the merits of incorporating integrated pest management (IPM) methods into husbandry practices. We also acknowledge the positive effects a healthy pasture invertebrate community contributes to natural parasite reduction, meaning conservation of this key resource plays an important role in sustainable parasite management. However, many compounds used to treat or control pests and parasites have the potential to negatively impact invertebrates such as dung beetles, flies and aquatic fauna. This can occur when the active ingredients or their metabolites are excreted in the manure and/or urine of treated animals, or leach into the environment as a result of poor storage, application or disposal. To minimise any environmental risks, all animal medicines licensed for use in livestock undergo an Environmental Risk Assessment (ERA), reviewed by the Veterinary Medicines Directorate (VMD), the competent authority in the UK, before any license is granted.

SCOPS and COWS are aware of the confusion and complexity around potential adverse effects of anthelmintics and ectoparasiticides on the environment. With this in mind, a joint SCOPS/COWS working group has been convened to provide producers and prescribers with clear information to aid informed decision-making regarding product choices. The initial advice from this group is summarised below:

Key points:

  • Animal health is critically important when a treatment decision is made and the choice of product should be discussed with the prescriber. The needs of the farm, including any environmental aspects, should be considered.
  • Treatment decisions are only one part of an integrated approach to parasite management developed with appropriate advice and input from advisers and included in the farm health plan. SCOPS and COWS aim to make the most up-to-date advice and guidance on parasite control and prevention available through their websites – and
  • To minimise environmental risk, it is vital that products are used, stored and disposed of according to the label instructions.
  • The Summary of Product Characteristics (SPC) includes information on environmental risks. It is important to check the SPC and to follow any advice on precautions to minimise the risk of damage to the environment. Useful information can be found on the VMD Product Information Database and using the VMD Product Information Database search function.
  • The activity of a medicine within the animal and the environment are NOT the same thing. The meat/milk withdrawal period of a product has no direct relationship to the risk to the environment.
  • Farmers, vets and SPQs/RAMAs should work together to reduce the risk of parasite infection in stock, with the emphasis on using as little product as possible but as much as necessary to protect the health and productivity of livestock. They should be fully informed about the potential environmental impacts and consider all aspects of sustainability, including optimising animal and environmental health.