Video on Sweet Itch vs Neck Threadworms in Horses

Updated June 10, 2025

In this episode of Ask the Vet, Dr. Lydia Gray and SmartPaker Dan go over how to know when a horse has sweet itch versus an infestation of neck threadworms. Equine neck threadworms (Onchocerca cervicalis) may be found in the nuchal ligament that runs from a horse's poll to their withers. Dr. Gray talks about why it’s important to consult your veterinarian and get a diagnosis of either condition, as well as one way to test if your horse does have neck threadworms.