In addition to controlling the environment in which horses live by minimizing exposure to tick habitat, certain direct measures can be taken to prevent tick infestations on horses. The most important is for you to inspect your horse daily so you can find and remove ticks in a timely fashion. The shorter time a tick is attached to the horse, the less risk for disease transmission; some reports say that tick removal within 24 hours is key to prevention of infection, especially of Lyme disease.
Skin checks are is particularly important for horses ridden on wooded trails or in deep grass areas. Use both hands and eyes to locate ticks on your horse. Look carefully along the belly, in the groin area, under the tail and mane, beneath the chin and within the armpits. Ticks can attach anywhere, but they particularly like the softer, less densely haired areas of the horse, which are often areas that are well-shielded from the environment.
Removal of a tick is done with care to avoid leaving any mouthparts embedded in the horse’s skin. Using tweezers, grasp the tick’s mouthparts close to the skin and apply gentle traction without twisting. Check that you have indeed removed all mouthparts and the head.
You might want to have the live tick sent to a lab for testing for Lyme disease. Consult your veterinarian as to the logistics of doing this. Otherwise, the tick can be destroyed with flame, by immersing it a jar containing alcohol or formalin, or by flushing it down the toilet.
Insecticides, such as permethrin or cypermethrin wipe-on or spray products, shampoos, or powders applied to a horse’s hair coat, are helpful. However, they aren’t guaranteed to prevent ticks from attaching, biting and transmitting disease. Topical treatments are effective for as long as the insecticide acts as a repellant, which usually wears off within 4-8 hours.
Research is currently looking into the canine Lyme disease vaccine for use in horses. It is being used off-label in endemic parts of the country, but research has found that canine Lyme disease vaccines induce only transient and low-magnitude antibody responses in horses. In general, one should not assume a horse is protected from infection with B. burgdorferi (the causative bacterium of Lyme disease)after receiving any of the three possible canine Lyme disease vaccines.