Equine Tick-Borne Diseases

The following post was a team effort, written by myself and Shelly Black, author of Healthy Horse Holistic Handbook.

Ticks are on the rise worldwide, bringing with them an increase in tick-borne diseases. In fact, in 2017, the CDC reported a record number of tick-borne diseases in the U.S. These tiny arthropods are reaching new regions and unfortunately, new species of ticks are still being discovered. One line of thought is that global warming may be a contributing factor to their increasing numbers.

Ticks pose a threat to many animals, including us, but for the sake of this post, we’ll focus on the three main diseases ticks can transmit to horses: Lyme disease, equine piroplasmosis, and anaplasmosis.

Lyme Disease

Lyme disease is mainly found in the northern, eastern, and western U.S. and is transmitted by what are commonly known as “deer ticks” (also called eastern or western black-legged ticks). The disease can affect humans, horses, dogs, and cats.

Symptoms of Lyme disease vary, and it can be difficult to diagnose. However, here are a few signs to watch out for in horses:

• stiffness
• lameness in more than one leg
• muscle tenderness
• muscle wasting (atrophy)
• lethargy
• behavioral changes
• general dullness
• skin sensitivity
• weight loss

Severely affected horses may show neurologic changes and uveitis (inflammation of the eye). Interestingly enough, joint swelling, which is common with humans and dogs, is rare in horses. Symptoms may not appear for years or conversely, they may show up shortly after the tick bite. Standard treatment is usually with antibiotics.

Equine Piroplasmosis

This disease is caused by a protozoal infection transmitted by ticks and affects horses, mules, donkeys and zebras. The parasites that cause equine piroplasmosis are found in Africa, the Middle East, Asia, Central and South America, Mexico, the Caribbean and southern Europe, but the disease is occasionally identified in northern Europe and the U.S., usually in transported horses. Like Lyme disease, animals may show few or no symptoms, but symptoms may include:

• rapid or shallow breathing
• depression
• general weakness
• weight loss
• jaundice
• dark-colored urine
• abortion in pregnant mares

In acute phases of the disease, horses usually have high fever (over 104 F), pale or yellow mucous membranes, and lower limb swelling. Standard treatment typically involves antioprotozoal drugs, supportive care, and occasionally, blood transfusions.

Equine Granulocytic Anaplasmosis

This disease is also transmitted by deer ticks but caused by a different bacteria than the one causing Lyme disease. It occurs more often in horses four years old or younger.

Symptoms can include:

• high fever (over 104 F)
• depression
• decreased appetite
• leg swelling
• stumbling
• ataxia

Antibiotics are typically used to treat anaplasmosis as well.

Another new tick species, known as the Asian Longhorned tick, is fairly new to the U.S. but has been identified in several states in the east and northeast. These ticks have been found on a wide range of hosts from small mammals, to livestock, to humans.

While the Asian Longhorned tick isn’t known to carry disease to horses (though they can transmit theileriosis to cattle), they often form large infestations on their hosts, causing stress, reducing growth, or possibly killing the animal due to blood loss. This isn’t likely to be an issue with horses (if they’re checked regularly), but this tick is just another one to be aware of!

How do you protect your horses from tenacious ticks?

Prevention is key where tick-borne diseases are concerned, says Dr. Joyce Harman in an informative article. But if you suspect your horse has contracted a tick-borne disease there is an herbal product available called Tic X that may help to naturally support the equine immune system. 

To help prevent ticks on your horse, keep your pastures and turnouts cleared of tall weeds and shrubs. Carefully check all your animals from head to hoof on a regular basis and especially after trail rides. Consider using safe and natural pest prevention products. You can find many listed in the Healthy Horse Holistic Handbook.

When heading out for a ride in areas that may have ticks, a great option for horses (and dogs) is Ticks-Off. Ticks-Off is not a repellent, but rather a tick deflective spray that is naturally effective without toxic chemicals.

Now, more than ever before, it is imperative to be informed and proactive for your health and your pets’ health. The old adage “An Ounce of Prevention is Worth a Pound of Cure” could not be truer than in regards to safely protecting your horses from ticks!

Sources:

Tick Borne Diseases on the Rise: Learn How to Protect Your Horse

Equine Piroplasmosis

Long-Horned Tick: Information for Livestock and Pet Owners