Banishing Lice: A Comprehensive Guide for Horse Owners

As a horse owner, one of the challenges you may face is dealing with horse lice infestations. These pesky parasites multiply rapidly, causing discomfort and irritation to your horse. Heavy infestations can lead to potential health issues if not addressed promptly.

In this guide, we'll explore effective strategies for identifying, preventing, and treating lice infestations, including clipping to ensure the well-being of your horse or pony.

Lice are small, wingless insects of around 2-5mm in size that can be found on the horse’s skin and hair. They can be seen by parting the hair and may look like yellow/white walking dandruff! 

Equine lice are species specific so they cannot be spread to humans. There are two main types of lice that affect horses: blood sucking lice and biting lice.

1. The biting louse: is the most common and can be seen moving about on the skin when you part the horse’s hair. These lice feed off dander and tend to be found on the main areas of the body covered with finer hair such as the head, neck, sides, and rump.
2. The Sucking louse: feed on the blood of the horse and tend to thrive in coarse hair. These lice prefer to reside in the horse’s feathers and at the base of the mane, forelock, and tail.  When parting the hair, these lice can be seen fixed to the hair shafts as they bury their heads into the skin and will be motionless rather than moving around.

Lice are incredibly contiguous and can affect any horse, even those in good health.  Young or older horses, those that are immunocompromised and equines with Cushing’s Disease are the most prone to lice infestation. 

Despite not being able to fly or jump, lice can be very easily passed from horse to horse and can spread quickly through a herd. It’s quite typical for young horses housed together during the winter to become infested. Long winter coats easily hide these parasites, letting them go unnoticed until spring.

If your horse is displaying any of these symptoms, you should always check for signs of lice before considering other causes of itching such as sweet itch or mites.

• Excessive itching and scratching.
• Hair loss or patches of rough, flaky skin.
• Presence of lice eggs attached to the hair shafts.
• Restlessness and agitation.
• Heavy infestations can lead to the horse looking poor. The horse may have a moth-eaten look to the coat with additional weight loss. Severe infestations with blood sucking lice can lead to anaemia.

Prevention is key when it comes to tackling lice in horses. Here are some proactive measures you can take to reduce the risk of infestation.

• Grooming tools, tack and rugs can spread lice from infected equines so it’s important to clean these items regularly, especially if they are shared between other horses. Disinfect your horse’s stable regularly too. Although they are unable to survive for long off of the host animal, lice and their eggs can be easily passed on to other equines via these objects.

• Monitor new arrivals: Quarantine and closely inspect any new horses to the yard before introducing them to your existing herd to prevent the spread of lice and other parasites.
• Practice good grooming habits: Regular grooming not only helps to keep your horse's coat healthy and shiny but also allows you to spot and address infestations early on.
• Use preventive treatments: Consider using louse repellent products, such as specialist shampoos, sprays, or powders to protect your horse from infestations. Ensure your horse is up to date with their worming treatments too.

2. Consider clipping your horse or pony. Removing a thick coat will help you see and effectively treat the infestation more successfully. Clipping the hair short also makes the habitat for the lice much less preferable for them to thrive. You will also be able to spot and treat wounds caused by your horse scratching more easily. 

A heavy-duty horse clipper will easily and efficiently clip through a thick winter coat. If the coat is unable to be washed beforehand, consider using a coarse clipper blade first to remove the bulk of the hair. For a smooth finish, you can then reclip the body using a medium or fine blade to leave a short, easy to maintain coat length.

3. Use insecticidal products: Your vet may recommend using insecticidal applications to target lice. Follow the instructions carefully to ensure safe and effective treatment. These formulations usually need to be repeated after a period of time to ensure the eggs and larvae are eliminated. It’s best to treat all the horses in the herd at the same time, even if lice have not yet been detected.

4. Treat the environment: In addition to treating your horse, it's important to treat the surrounding environment, including stables, bedding, and grooming tools. Wash numnahs, rugs and headcollars to eliminate lice eggs or larvae.