Itching of the tail in horses: the causes

Small hairworm: most common cause

The small hairworm (Oxyuris equi) is the direct cause of intense tail itching in many Irish horses. The female lays her eggs around the anus, causing a sticky, yellowish secretion. This irritates the skin and the horse literally rubs itself bald. Infection occurs via contaminated feed or water. Deworming with ivermectin or moxidectin effectively addresses the hairworm, but resistance is increasing. In case of doubt, have a faecal egg count done to determine the correct worm burden. Record the deworming date and product used in the EquiSight horse file, so you have a complete overview.

Skin mites and mange

Mange mites (Chorioptes equi) prefer the hind legs and tail base. In long-haired breeds such as Friesians and Tinkers, the mite is often unnoticed in the feathering and hoof hair for months. Typical features are intense itching, crust formation and skin thickening. Treatment consists of bathing treatments with permethrin or other acaricides, combined with keeping the stable clean. One treatment is never enough: repeat after 14 days to also reach the newly hatched mites.

Allergies as a lesser-known culprit

Insect bite hypersensitivity (IBH), caused by Culicoides midges, causes severe tail itching in addition to itching along the mane. About 5 to 10 percent of horses in Ireland have IBH, but contact allergies to soap, rubber tail guards or certain shampoos can also cause skin irritation. IBH horses are recognizable by seasonal patterns: symptoms typically begin in April and decrease in October. Prevention consists of fly sheets, stabling at dusk and insecticide treatment of the skin.

Poor hygiene and grooming mistakes

Shampoo residue, sweat or grease in the tail area breaks down the skin barrier. A tail that is brushed or rinsed too infrequently accumulates dirt around the tail base. But the opposite — washing too frequently — removes the protective sebum. Always rinse thoroughly after every wash and dry the tail base well, especially in cooler temperatures. Using conditioner? Make sure you rinse it out completely.

Other causes at a glance

• Ringworm (Trichophyton): fungal infection that also affects the tail base and causes crusts
• Pityriasis (dandruff): dry, flaky skin due to hormonal or nutritional fluctuations
• Deficiency of omega-3 fatty acids or zinc: leads to dry, irritable skin
• Skin tumour (melanoma): particularly in grey horses around the anus and tail base
• Red mite (Dermanyssus gallinae): can infect the horse from chicken runs in the stable

When to call the veterinarian?

Tail itching lasting longer than two weeks or accompanied by wounds, crusts, hair loss or poor general condition requires veterinary assessment. The same applies if deworming brings no improvement within ten days. Bring your treatment history to your appointment: which deworming product, when, which products do you use for grooming? EquiCoach helps you formulate the right questions and order the possible causes before your conversation with your veterinarian. This way you go to the consultation well prepared.

Keeping track of complaints makes a difference

Tail itching often has a pattern: seasonal, after certain feed changes or after contact with new stable mates. By systematically recording complaints, treatments and responses in the horse file of EquiSight, you see these patterns faster. Record per incident: start date, severity on a scale of 1 to 5, products used and the result. Three weeks of consistent recording gives your veterinarian plenty of useful information.