How to treat lice in horses

An itch you just can’t scratch is irritating for anyone. But for horses covered in hair it can be maddening! Parasites such as horse lice are one of the most common causes of itching in horses and are unfortunately very common.

As a responsible owner, you’ll know how to spot the signs your horse is feeling ill, upset or uncomfortable. And having lice is bound to leave them feeling under the weather. Read our guide on how to treat lice in horses and get them back to full health in no time. It’ll be well worth the effort.

Your horse doesn’t just rely on you for love and care. They also need you to arrange veterinary treatment if you can’t manage the problem yourself. The right horse insurance will help you get them the right care when they need it most. The team at Equesure can help you source the right cover for you.

Itchy horse? It could be lice!

There are a number of different reasons why your beloved equine might be itching. But a lice infestation is one of the more common ones. A horse can be afflicted by lice at any time of year but the most common time is during the cooler, damper periods found in the UK in winter and early spring. Lice numbers tend to drop during the warmer spring and summer months.

Before investigating other causes of itchiness, such as sweet itch, if your horse or pony is itching then it’s always wise to rule out lice and other parasites, such as mites, first.

We love our horses and often spend a lot of time worrying about them. Worms and other internal parasites are a big concern for many owners. But external parasites like lice can be a major source of irritation for your horse. As well as having a potentially big impact on their health and general wellbeing.

Horses infested with lice are likely to be very uncomfortable and may even start to go downhill in other respects, too. All that itching can soon develop into nasty skin sores that lead to other, more serious infections. Indeed, some varieties of lice are blood sucking so a severe infestation can even cause anaemia, particularly in young horses.

If you become aware of lice on your horse or their field mates, then it’s vital to act fast before the situation gets worse. A skin problem that’s left untreated will soon become uncomfortable for the horse and could constitute a potential welfare concern.

The BHS has a dedicated team of volunteers and field officers who work to improve the lives of all horses and prevent equine suffering. Details on how to report a horse to the BHS are available on their website.

Having horse insurance in place encourages owners to seek professional advice without the worry of a big bill.

Getting to know the pesky critters – a guide to the common types of equine lice

If the mere thought of lice makes you wince and come over all itchy, then be warned. We’re about to discuss the nitty gritty of these unfortunate pests. The different varieties your horse could be afflicted with, the lifecycle of the louse, and other such nasties! So, let’s dive right in!

There are two main species we need to be concerned with here in the UK. Adult lice of both types are tiny, wingless insects with a flat, segmented body. They have three pairs of legs and are usually light brown or yellowish in colour. Below are details on the two varieties of lice.

Bloodsucking lice (Haematopinus asini)

This bloodsucking variety is the larger of the two measuring between 3-3.5mm when fully grown. This makes them somewhat easier to spot during routine grooming or lice inspection. They feature a long, pointed head and strong mouthparts used for penetrating the horse’s skin. They feed on the horse’s blood and other tissue fluid and are the most common type to be found.

If searching for these little bloodsuckers you’re more likely to find them among the longer hairs of the mane, tail and fetlocks. They tend to move slowly and you’ll often find them with their mouthparts already embedded in the skin. As with human lice you’ll find their eggs (nits) visibly attached to the hair follicles. These can easily be mistaken for dandruff.

Biting lice (Damalinia equi)

Less common than the bloodsucking variety, the biting lice feed on the top flaky layer of dead skin so are usually found living close to the skin. The two types can be told apart by the fact that biting lice have a broad, rounded head and dark abdominal stripes. They’re also smaller (measuring around 1-2mm) which makes them more difficult to spot.

The eagle-eyed owner might find them along the back and sides of the horse. They tend to be more mobile and faster than the other variety. However, if they’re left untreated then they may spread over the entirety of the horse’s body.

Both species of horse lice spend their entire lifecycle of between 20 and 40 days on the body of the horse. The eggs are oval, pale and translucent and are deposited by adult female lice on the hairs of the infested horse. These eggs hatch in between five to 20 days and become small, pale larvae called nymphs. These small adults undergo three moults before becoming fully grown adult lice.

You need to know if your horse is infested with biting or sucking lice because the treatments can be slightly different. Your vet will be able to advise on the best course of action for your particular infestation.

How do I know if my horse has lice?

There are a number of classic signs of lice infestation worth looking out for. The numbers of lice on your horse can go up exponentially if you haven’t kept a careful eye out. Have you noticed any of these common symptoms?

Coat in poor condition
By far the most common sign is if the horse's coat becomes dull, unkempt and even rather ‘moth-eaten’ under the mane, along their back and around their tail. The presence of dandruff and flaky skin, patchy hair loss on the neck or shoulders, or raw, inflamed skin can also suggest lice are at work. Another common sign of horse lice is if they develop matted hair in the mane, tail or body. A horse with a lice infestation can look like a sorry sight indeed!

Weight loss
Horses with a weak immune system, such as the sick, old or very young, are more susceptible to lice. However, when larger numbers of horses are kept together (for example in stables during the winter), lice can affect even the healthiest of adults. Decreased muscle tone and weight loss can occur, so this is another reason to regularly weigh your horse. In the case of bloodsucking lice, severe infestations have even led to anaemia, which will require a blood sample for diagnosis. The small wounds these lice can inflict can also become infected.

Biting and itching
Often the very first sign you’ll notice of an infestation will be changes in your equine friend’s behaviour. The intense itching caused by lice will make them scratch and even bite their skin. You might see them rubbing themselves against fences, walls or anything they can get access to which will provide relief from the constant itching. As you would expect, if untreated this will soon lead to the patchy coat and raw skin mentioned above. Remember if a horse is unhappy or uncomfortable then they might also appear listless or even colicky. A lethargic horse is always worth investigating further.

Presence of lice and eggs
Not every horse will display obvious physical or behavioural changes because of lice. So, the only way you might discover your trusty friend has lice is if you see them in the flesh! While they are small, luckily you can usually see them with the naked eye in the horse’s coat. If you use a magnifying glass and powerful pen light then it’s even easier. Choose a well-lit place and carefully part the hairs around the affected area. The layers of the coat and skin can then be carefully examined. They tend to live close to the base of the hairs. But if the horse is sweating then they are more likely to come to the surface.

If, after an inspection, you’ve found lice, or even if you’re still unsure, give your local vet a call and they can make a diagnosis. A professional will be able to rule out any other possible conditions, and outline the correct course of treatment. When you’ve got horse insurance, help is always close at hand.

Are certain horses more prone to lice?

As we’ve already mentioned, just because a horse has lice doesn’t mean they’re in poor condition, rarely groomed, or have been kept in crowded conditions. Neglected horses can be more likely to have lice. But just because yours has lice doesn’t mean you should feel guilty. You just need to get them the help they need.

And just because one or two horses within a herd are infested with fleas, it doesn’t mean all the others will be to the same extent. The others may or may not even have lice. Some horses may be more irritated or possibly even allergic to the lice bites or irritation.

It’s fairly common for groups of young horses housed together during winter months to become infested with lice. After all, with their long winter coats it’s easy for large numbers of lice to multiply unnoticed. So when spring is approaching, make sure to check them over carefully.

In the early stages of low-level lice infestations, it’s all too easy to miss the tell-tale signs as they may produce little evidence of skin irritation. While a heavy infestation will probably cause much more intense itching, hair loss, areas of raw skin and infections.

It does seem that horses who are stressed, unwell, malnourished or suffering from diseases such as Equine Cushing’s are more likely to develop an infestation.

Having horse insurance is a vital tool in your armoury when getting treatment for such diseases.

How lice spread

Just as with lice in humans, lice are most often spread by direct contact between horses or by sharing brushes. So, horses living close together during the cold winter months can easily pass them between herd members. While lice need a horse’s body to survive, it is possible for them to live for a few days in rugs, grooming brushes and tack. Or even on paddock fences and trees that horses rub against.

When you introduce a new horse to a herd, lice and other issues can easily be passed between the two. Meaning that a trip to the vet could soon be in order. If you’ve fostered a horse from a charity or rescue centre, never assume that horse insurance is covered.

Top treatment tips to rid your horse of lice

If you discover your horse has lice, you don’t need a vet to diagnose the problem. But it would be a good idea to consult one when it comes to treating them and preventing further infestations. If you haven’t had much experience of dealing with lice infestations in horses then you might not have much of a chance against them. They may be tiny but that doesn’t mean they’re not a formidable opponent! Keep some of these top tips in mind if you find lice on your horse.

• Speed is of the essence when dealing with lice on your horse as every day will add yet more lice! A good first step in treating lice in horses is to clip their coat. The longer and thicker the coat, the more inviting it is and the better chance they have of avoiding any treatment products you use.
• Dirt and dust on the horse’s coat has been known to reduce insecticide effectiveness. So, make sure to brush the horse before treatment. Clean and treat all grooming equipment with insecticide after use.
• Treatment products come in various forms including shampoos, powders, lotions and sprays. Always apply them as described on the packaging.
• Insecticides will kill adults and immature lice but not the eggs. A second treatment will be needed two to three weeks after the first one.
• Particularly in cold or bad weather, shampooing your horse might be impractical. If so, an insecticide in an alternative form might be more useful.
• Never use lice treatments intended for humans, dogs or any other animals other than horses. These will not work and may even cause severe skin reactions and/or hair loss in horses.
• Many treatments require the skin to be well coated in order to be effective. But try to avoid any areas of sore or broken skin during application. And make every attempt to avoid the horse’s eyes, mouth, nostrils, and genitals.
• Wear gloves and other protective gear to minimise breathing it in or contact with your skin, eyes.
• Pay close attention to the usual sites where lice are found. Be aware both types of lice can be found over larger areas in cases of heavy infestation.
• Thoroughly treat and clean any potentially infected tack, bedding, rugs, or grooming equipment. Lice could be hiding in the surrounding environment and easily reinfect your horse. Rugs need to be washed and dried at a high temperature to kill the lice. Repeat this every time you treat the infected horse.
• It’s also wise to change their straw or bedding. And take the opportunity to spray or scrub down stable walls or wooden fences.
• Some horses can be more sensitive to the products than others. You may notice skin sensitivity, itchiness and rashes. Or even hair discoloration or hair loss where you have applied the product. If you notice such signs then wash the horse with a mild, non-insecticidal shampoo and rinse with large amounts of water. Speak to your vet if you spot signs of sensitivity.
• There are a number of natural alternatives to these commonly used medications. Speak to your vet who might be able to recommend alternatives. Interestingly, studies have raised the possibility of using essential and non-essential oils in the control of lice. Tea tree, lavender, peppermint, eucalyptus, and clove have all been found to work in the control of biting lice in particular.
• Giving their immune system a boost is a great way to aid recovery from a lice infestation. So, check their diet and see if there’s anything worth adding as a supplement.
• If they’re suffering from a disease such as Equine Cushing’s that makes them more susceptible to lice then be sure to treat that health problem, too!
• Once you’ve treated your horse, keep them away from other horses that might be infected with lice.

How to prevent a reinfestation

As a caring horse owner, you’ll obviously act fast to treat the affected horse and rid them of the lice infestation. However, there are some extra measures worth taking to help prevent the problem from arising in the first place. Or stop a reinfestation in its tracks.

• Keeping up with a regular routine of brushing and grooming is essential, particularly during the winter months.
• Particular vigilance is needed in the late winter and early spring months. Our UK climate creates the perfect conditions for lice to develop hidden under those inviting seasonal rugs.
• Clean and sterilise tack, saddles, saddle pads, and grooming brushes and anything else that comes into contact with the horse. Make this a regular part of kit care.
• Carefully check new horses for signs of lice before letting them mix with any other horses or the surrounding environment. If you find lice then they need to be isolated and treated before introduction to their new field mates. This is a good opportunity to check for other health conditions, too.
• Whether you’re out on a hack together with friends or at a big competition, try to avoid getting too close to unknown horses. This is probably a wise safety measure in any event.
• Horse care can be expensive. So, buying or borrowing second-hand rugs, tack, or stable tools in good condition can be a great money-saving idea. However, make sure to clean and sterilise anything before use.
• If possible, use different equipment for each horse you manage and store it separately. This will help prevent any cross contamination. Sharing equipment can spread many other skin problems such as ringworm and mange.
• When treating a horse for an existing case of lice, make sure to treat all other horses that have had contact with them. Lice are so easily passed on that any horses stabled or turned out together are also likely to be affected.

Get them protected with horse insurance through Equesure

Whether they’re a sprightly youngster or a dependable veteran, having the right horse insurance in place is vital to deal with even the most straightforward condition.

With over 60 years of combined equestrian knowledge, Equesure’s team will create a bespoke plan tailored to you and your horse.

Our policies offer many cover benefits to suit most budgets. These include:

• Vet’s fees cover up to £10,000 per incident but with an unlimited number of claims within the policy year.
• Saddlery and tack cover available.
• Additional discounts may also be available if you insure more than one horse.

Call our dedicated team today to discuss your options and get a quote for horse cover.

Policy benefits, features and discounts offered may very between insurance schemes or cover selected and are subject to underwriting criteria. Information contained within this article is accurate at the time of publishing but may be subject to change.