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Equine worming protocols: tackling the increasing problem of anthelmintic resistance

02 May 2024
10 mins read
Volume 8 · Issue 3


Anthelmintic resistance is a growing global problem in the equine sector. Only three classes of anthelmintics are authorised for use against equine nematodes, and resistance to all of them has been reported in the UK. Resistance to praziquantel, which is effective against equine tapeworms, has also been reported. The use of anthelmintics therefore needs to be restricted, and adoption of diagnostic-led targeted treatment regimens is essential to protect efficacy and slow further development of resistance. This article discusses current recommendations regarding helminth treatment and control in horses and summarises Controlling ANTiparasitic resistance in Equines Responsibly and British Equine Veterinary Association guidelines published in 2024.

Equine helminth control practices require urgent and sustained change. Anthelmintic resistance is rapidly growing in the UK and overseas. Several sector groups have produced updated guidance for control in the UK, including the British Equine Veterinary Association (BEVA) ‘ProtectMEToo’ guidelines (BEVA, 2024) and the Controlling AN-Tiparasitic resistance in Equines Responsibly (CANTER) guidelines (CANTER, 2024). The latter was established in 2022 and is a voluntary pan-industry group, currently chaired by the Veterinary Medicines Directorate. In the UK, authorised equine anthelmintics are classified as prescription-only medicines that can be prescribed by veterinary surgeons, veterinary pharmacists and suitably qualified persons, and CANTER is aiming to produce best practice guidelines relevant to each of these groups. The BEVA guidelines focus on equine veterinary surgeons. In addition to addressing anthelmintic resistance, both guidelines consider important ecotoxicity concerns of anthelmintics (Haseler et al, 2023).

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