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Parasite Control
What are parasites?
Parasites are living organisms that depend on another animal, such as livestock or pets, for their food and survival. External parasites, like fleas, ticks and mites, inhabit the skin or hair of an animal. Internal parasites, like various worms and protozoa, reside within body tissues or organs. These organisms are highly adaptable and can be found in a wide range of environments, affecting animals of all ages and species.
How do parasites affect animal health and welfare and human health?
The presence of parasites in livestock or pets can have significant health and welfare consequences. Heavy or persistent infestations may cause discomfort, irritation and stress, leading to excessive scratching, open wounds on the skin or hair loss in the case of external parasites. Internal parasites often interfere with digestion and nutrition absorption, resulting in poor growth rates, weight loss, anaemia and a weakened immune system. Young, elderly or immunocompromised animals are often more severely affected.
Beyond individual health, parasites can impact the overall productivity and wellbeing of livestock herds or flocks, leading to increased resource needs such as feed, decreasing the sustainability of production, and increasing economic losses for farmers. In companion animals, parasites can reduce quality of life and sometimes pose a risk of transmission to humans (known as zoonotic disease). An example is Toxocara canis, a type of roundworm found in dogs which can infect people and sometimes result in severe health problems like visceral or ocular larva migrans. By managing Toxocara canis in dogs, we not only support animal health but also safeguard people from these kinds of infections, showing how closely linked animal and human health can be.
How can we ensure the responsible use of anti-parasitic medicines?
Ensuring the responsible use of anti-parasitic medicines is essential for both animal welfare and sustainable food production. These treatments should be administered only when necessary, based on veterinary guidance and according to recommended dosages. NOAH have been involved in several collaborative industry initiatives advocating for responsible use of anthelmintics in sheep through SCOPS, cattle through COWS and horses through CANTER. It is also crucial to always read and follow the product labels, and to seek professional advice from vets or Suitably Qualified Persons (SQPs) when selecting and administering treatments.
This approach is at the heart of the NOAH ‘Use it Right, Treat them Right’ campaign, which encourages pet owners to use parasite treatments correctly by understanding the instructions and consulting professionals. Through this campaign, we aim to equip pet owners with the knowledge they need to use these medicines safety and effectively.
Regular monitoring of animals for parasite presence, careful maintenance of health records, and the adoption of integrated parasite management practices, such as improved hygiene, strategic pasture rotation, and preventative care, are all important measures. Using a combination of these strategies can help control parasite populations, reduce the likelihood of resistance, and support animal health and sustainability.
How are anti-parasitic medicines regulated?
In the UK, anti-parasitic medicines are regulated by the Veterinary Medicines Directorate (VMD). The VMD assesses these products for safety, quality, interactions with the environment, and effectiveness before gaining approval for use in animals. This includes an Environmental Risk Assessment (ERA), which evaluates the potential impact of the medicine on ecosystems, such as effects on soil, water and non-target organisms. Once authorised, both the VMD and product manufacturers continue to monitor these medicines for side effects and ensure strict standards are maintained through their use in veterinary practice.
Further Reading
- European Scientific Counsel Companion Animal Parasites (ESCAAP) Website (Available at: https://www.esccap.org/)
- BVA, BSAVA and BVZS policy position on responsible use of parasiticides for cats and dogs (Available at: bva-bsava-and-bvzs-policy-position-on-responsible-use-of-parasiticides-for-cats-and-dogs.pdf)
- European Medicines Agency Environmental Risk Assessment for Parasiticide Veterinary Medicinal Products used in Companion Animals (Available at: Environmental risk assessment for parasiticide veterinary medicinal products used in companion animals – Scientific guideline | European Medicines Agency (EMA))
- Sustainable Control of Parasites in Sheep (SCOPS) Website (Available at: SCOPS | Sustainable Control of Parasites in Sheep)
- Control of Worms Sustainability (COWS) Website (Available at: Promoting Sustainable Control of Cattle Parasites – COWS – Promoting Sustainable Control of Cattle Parasites)
- Controlling Antiparasitic Resistance in Equines Responsibly (CANTER) Website (Available at: Home – CANTER)