Lymphangitis in Horses – Causes, Symptoms, and Treatment

Lymphangitis in horses is inflammation of the lymphatic vessels, and it is one of the few conditions on a yard that can take a sound horse and leave it three-legged and feverish between morning and evening stables. The classic picture is a hind leg swollen to twice its normal size, hot, painful to touch, and a rectal temperature well above 38.5C. It is a same-day veterinary call, not a wait-and-see.

This guide covers what lymphangitis actually is, the three forms vets distinguish, how to tell it apart from cellulitis and from ordinary filled legs, what treatment involves, and what genuinely reduces the chance of a second episode. It also corrects a piece of yard folklore about the pitting test that appears on a great many websites, including, until this update, our own.

What Is Lymphangitis in Horses?

The lymphatic system is the body’s drainage network. It is a parallel circulation of thin-walled vessels that collect the fluid constantly leaking out of capillaries into the tissues, filter it through lymph nodes, and return it to the bloodstream. Unlike the arterial system it has no pump of its own. Lymph is moved by the squeezing action of surrounding muscle and by the flexion of joints such as the fetlock and the hock. A horse standing still is a horse whose lymphatic system is barely working.

Lymphangitis is inflammation of those vessels. When bacteria enter through a breach in the skin of the lower limb and track up the lymphatics, the vessels become inflamed and their valves stop functioning. Drainage fails, fluid backs up, and the leg swells rapidly and painfully from the coronet upwards. The MSD Veterinary Manual and the owner-facing Merck Veterinary Manual entry both define lymphangitis as inflammation of the lymphatic vessels, usually caused by a bacterial infection that spreads to them. Note when you read them that both entries are given over almost entirely to Corynebacterium pseudotuberculosis, the ulcerative form described below, rather than to the acute case most UK and SA owners actually meet.

The historical name is Monday morning leg, from the era of working carriage and dray horses that were kept on a full working ration over a rested weekend and presented swollen on Monday. The day of the week is irrelevant. The mechanism is that lymphatic drainage depends on movement, so a fit horse abruptly stood still while still being fed for work develops fluid stasis in the limb.

Worth knowing, because the two are constantly conflated: Monday morning disease more usually refers to azoturia, the exertional rhabdomyolysis or tying-up seen in the same draught horses under the same management. The names share an origin and a stable-management cause, but the conditions are unrelated. If a source uses the two terms interchangeably, treat the rest of it with caution.

The Three Forms of Lymphangitis

Three patterns are recognised, and they differ enough in cause, treatment and outlook that the label matters.

Sporadic Lymphangitis

The common UK and South African presentation, and the one almost every owner reading this will be dealing with. Bacteria, typically streptococcal or staphylococcal species that live harmlessly on the skin, enter through a small wound, a mud fever lesion, a cracked heel or an insect bite below the hock. The infection ascends the lymphatics and produces swelling, fever and severe pain. It is not contagious between horses. The reference entry for equine lymphangitis covers the clinical picture in summary form.

Ulcerative Lymphangitis

A slower, more chronic form. Firm nodules develop along the course of the lymphatic vessels, then ulcerate and discharge thick pus. It tends to recur and to grumble on for weeks rather than resolving cleanly. The organism classically associated with it is Corynebacterium pseudotuberculosis, the same agent responsible for the condition known in the western United States as pigeon fever, although various streptococci can produce a similar picture. C. pseudotuberculosis is uncommon in the UK. See the ulcerative lymphangitis entry for detail.

The practical significance for an owner is that ulcerative cases are much less likely to respond to a routine course of treatment. The Merck Veterinary Manual puts ulcerative lymphangitis and internal infections at a month or more of antibiotics. These are also the cases where your vet will want to culture the discharge rather than treat empirically.

Epizootic Lymphangitis

A genuinely contagious fungal disease caused by Histoplasma capsulatum var. farciminosum, producing spreading nodules and ulcers along the lymphatics of the limbs, neck and head. It is exotic to the UK and to South Africa. Where it does occur, principally in parts of East Africa and Asia, it is a serious welfare problem in working equids and is subject to notification requirements in many countries. Older texts call it African farcy. UK and SA owners will not meet it, but the term appears in search results and in reference works, which is the only reason to know it.

How to Recognise Lymphangitis on the Yard

The onset is fast and the horse looks genuinely ill, which is the single most useful thing to hold on to. Take a temperature before you do anything else; if you are not confident with normal values, our guide to taking a horse’s temperature, pulse and respiration sets out the baselines. Typical findings are:

• Rapid, dramatic swelling of one limb. The leg can double in circumference within a few hours. Swelling usually starts low, around the pastern and fetlock, and tracks upwards over the cannon towards the stifle or the groin.
• Marked heat compared with the opposite leg, judged with the back of the hand along the whole limb rather than one spot.
• Severe pain. The horse flinches from light contact and objects to the foot being picked up. This is the finding that separates it from benign swelling most reliably.
• Severe lameness, commonly grade 4 to 5 on the 0 to 5 AAEP scale, occasionally non-weight-bearing. Our overview of lameness in horses explains the grading.
• Fever. Rectal temperatures of 39C to 40.5C are usual against a normal adult range of 37.5C to 38.5C, the healthy range the British Horse Society publishes. An earlier version of this page gave that normal range as 37.2C to 38.3C, a conversion of the American convention; on the correct range anything above 38.5C is already a raised temperature, which is why the 38.5C figure at the top of this page is the one to act on.
• Systemic illness. Dull, off feed, raised heart and respiratory rate, sometimes shivering. Many horses go quiet several hours before the leg looks obviously wrong.
• Serum weeping. As the limb becomes very oedematous, straw-coloured fluid may bead through the skin pores or run from cracks. This is characteristic and is worth reporting to the vet.
• Cording. In some cases firm, tender lines can be felt running up the limb, which is the inflamed lymphatic chain itself.
• A portal of entry, if you look for it: a scratch, a scab, a cracked heel, a puncture. Frequently there is nothing visible, and its absence does not rule anything out.

Hind limbs predominate. In the closest published equivalent, a case series of equine limb cellulitis reported roughly three-quarters of cases in a hind limb. There is no good evidence of a right-versus-left predilection, despite the claim appearing in a number of online sources.

Lymphangitis vs Cellulitis: What Actually Separates Them

This is the question owners actually search for, and searches for the difference between the two have been rising while interest in the head term has fallen. It deserves a straight answer rather than the usual hedge. Our full guide to cellulitis in horses approaches the same problem from the other side.

The honest position is this. Cellulitis is infection of the subcutaneous tissue spreading diffusely through it. Lymphangitis is infection and inflammation running along the lymphatic vessels. In a real horse with a hot fat leg the two overlap heavily and frequently coexist, because swelling of the subcutaneous tissue compresses and inflames the lymphatics passing through it. Many experienced vets will use the terms loosely in the field, and the emergency treatment is the same for both.

Where the distinction earns its keep:

• Cording and serum weeping point towards lymphangitis. Palpable firm lines tracking up the limb, and fluid beading through the skin, indicate the lymphatics are involved.
• Recurrence risk is the real difference. Lymphangitis damages valves in the lymphatic vessels. Once those are scarred, drainage never fully recovers, and each episode makes the next more likely. A horse that has had three episodes is managing a permanent condition, not recovering from an infection.
• Residual thickening is far more characteristic of lymphangitis. A limb that never returns to its original circumference is the signature.
• It changes the conversation, not the first injection. Nothing about the distinction should delay the phone call.

If your vet uses one term one week and the other the next, they are not being careless. They are describing a spectrum that does not have a clean line down the middle.

The Full Swollen Leg Differential

A swollen leg is a sign, not a diagnosis. Getting the label right changes what happens next, and several items on this list are more urgent than lymphangitis rather than less.

For swellings that are soft, cool and longstanding rather than acute, our guide to windgalls in horses covers that end of the range. For skin-led problems, see the most common horse skin diseases and rain scald.

Why the Pitting Test Will Not Settle It

A widely repeated piece of advice says that you can distinguish lymphangitis from stocked-up legs by pressing a thumb into the swelling: if it pits, it is lymphangitis. That test does not work, and it is worth correcting plainly because it appeared in the previous version of this article.

Pitting indicates soft, fluid-filled oedema sitting in the tissues, and dependent oedema in a horse that has stood in overnight pits readily and comfortably. The trouble is that an acutely infected limb pits too. Pitting oedema is one of the typical presenting signs of equine limb cellulitis set out in the British Veterinary Association’s In Practice clinical review (Braid, 2024), alongside acute diffuse swelling, heat and pain on palpation. The thumb therefore cannot separate the two, because both of them pit. The limb that is hard and will not pit is the chronically thickened, repeatedly affected one, not the acute episode.

So the pitting test tells you very little on its own. The discriminators that actually work are simpler:

1. Is it hot? Stocked-up legs are cool.
2. Is it painful? Stocked-up legs are not.
3. Is there a fever? Take the temperature. Filled legs do not cause one.
4. How many legs? Stocking up is usually two or four. Lymphangitis is usually one.
5. Does walking disperse it? Filled legs improve within minutes of movement. Lymphangitis does not.

Any one of heat, pain or fever moves the horse straight into the vet-today category regardless of what the thumb test suggests.

Why Lymphangitis Develops

Almost always, bacteria that live on normal skin get past the skin barrier and into tissue that cannot clear them. The common routes in are:

• Mud fever and pastern dermatitis, which is the single most cited portal of entry in UK horses. Broken, softened skin in a wet winter is an open door.
• Insect bites. Midge and fly bites on the lower limb, particularly in summer. See treating a horsefly bite and, for the allergic end of the spectrum, managing sweet itch.
• Small puncture wounds from wire, splinters or overreaching, often too small to have been noticed.
• Cracked heels and coronet band injuries.
• Overreach and tread injuries from a hind shoe, which is worth raising with your farrier if it keeps happening.
• Previous episodes. Scarred lymphatic valves are the biggest single risk factor for the next one, and later episodes often have no identifiable trigger at all.
• Cushing’s disease (PPID), which suppresses immune function and predisposes older horses to recurrent infection. Our fuller guide to equine Cushing’s disease and the article on pergolide cover diagnosis and treatment.
• Obesity and metabolic disease, which worsen limb oedema and make every part of management harder.
• Prolonged stabling, especially a fit horse suddenly stopped, which is the original Monday morning pattern.

Is Lymphangitis in Horses Contagious?

This comes up constantly on shared yards and deserves a form-by-form answer rather than a blanket one.

• Sporadic lymphangitis is not contagious. The bacteria involved already live on every horse on the yard. What made your horse ill was a breach in its own skin, not exposure to another animal. No isolation is required.
• Ulcerative lymphangitis needs sensible hygiene. C. pseudotuberculosis survives in soil and bedding and can be moved between horses on flies, grooming kit, boots and bandages. Where a case is confirmed, use dedicated equipment, wear gloves, dispose of dressings carefully and do not share bandages. This is not the same as a contagious disease outbreak, but it is not nothing either.
• Epizootic lymphangitis is contagious and spreads horse to horse. It does not occur in the UK or South Africa.

Because the organisms involved are opportunists in wounds, keep the horse’s tetanus cover current as a matter of routine. Our guide to tetanus in horses explains the vaccination schedule.

Treatment: What the Vet Will Do

Lymphangitis is a same-day call. Ring the vet, take a temperature, and note it down with the time. Do not give bute or anything else from the yard cupboard before the vet has seen the horse: pain relief masks the lameness and the fever they need to assess, and it can complicate the choice of drugs afterwards.

Treatment attacks several fronts at once.

1. Antibiotics

Systemic antibiotics are the cornerstone. The choice of drug, route and duration is a veterinary decision that depends on severity, the horse and local prescribing policy, and it is not something to plan from an article. Two things are worth knowing as an owner. Courses are usually shorter than owners expect. In the only published survey of UK practice, covering 268 vets treating distal limb cellulitis, antimicrobials were most often prescribed for five days, and the longest course any respondent reported for any treatment was ten days (Braid and Ireland, Equine Veterinary Education, 2021). If you have read that a fortnight is the minimum, including in the previous version of this article, that is not what UK vets prescribe, and a five-day course is not your vet cutting corners. What matters is finishing the course you are actually given: stopping early because the leg looks better is one of the most common routes to a relapse, and running on longer than prescribed is its own problem. In recurrent or non-responsive cases, particularly suspected ulcerative disease, your vet may want to culture a sample to direct the choice rather than treating empirically.

2. Anti-inflammatories and pain relief

Non-steroidal anti-inflammatory drugs are given both for welfare and because they are functionally part of the treatment. A horse in too much pain to walk will not move, and lack of movement directly worsens lymphatic stasis. Dose and duration are for the vet to set.

3. Cold hosing

Cold hosing the limb for around fifteen to twenty minutes, two or three times daily in the acute phase, reduces inflammation and provides useful analgesia. Ice boots and cooling wraps work as well. There is no benefit in hosing for hours at a stretch.

4. Controlled movement

Once the horse is comfortable enough to move, hand walking becomes the most powerful thing you can do. The lymphatic system has no pump other than muscle action, so a box-rested horse with lymphangitis frequently gets worse rather than better. Short, frequent sessions, building gradually, and started when your vet says so and not before. A horse that is genuinely unwilling to bear weight should not be walked.

5. Compression

As the acute swelling starts to come down, a stable bandage or a purpose-made compression garment helps stop fluid re-accumulating overnight. Compression must be applied competently, with adequate padding and even pressure; a badly applied bandage creates the next problem. If you are not confident, have your vet or an experienced yard manager fit the first one and show you.

Nursing the Horse at Home

• Take and record a temperature twice daily. It is the most sensitive early indicator of whether treatment is working, and a rising temperature after an initial fall needs reporting the same day.
• Photograph the limb daily from the same angle and distance. Day-to-day change is hard to judge by eye and a photo sequence removes the argument.
• Measure the circumference at a marked point on the cannon with a soft tape. Numbers beat impressions.
• Keep the skin clean and dry and leave any scabs to your vet rather than picking them off.
• Watch the opposite limb. A horse offloading one leg for days is at risk of supporting-limb laminitis.
• Watch for boredom behaviours if the horse is confined; our piece on box walking covers management of a stressed, stabled horse.

What Treatment Costs and What Insurance Covers

No honest figure can be given for this, and any article quoting a precise range is guessing. UK and South African equine practices do not publish tariffs for lymphangitis, and the variation between a single yard visit with a course of tablets and a week of hospitalisation is enormous. What is useful is knowing what drives the bill, so you can ask your own vet for an estimate against your own case:

• Number of visits, and whether they fall out of hours
• Whether the horse can be managed on the yard or needs hospital admission with intravenous treatment
• Length of the antibiotic course, and whether culture and sensitivity testing is needed
• Ultrasound or radiography if a septic joint or a foreign body has to be ruled out
• Whether complications develop, which is where costs escalate sharply
• How many times it recurs, which is the factor that matters most over a horse’s lifetime

On insurance, the point worth acting on early is that lymphangitis recurs. Most policies will cover a first episode under veterinary fees, subject to the excess and any per-condition limit. Once the horse has a history, insurers commonly apply an exclusion for that limb or for the condition at renewal. Read the renewal terms rather than assuming continuity, and tell your insurer promptly, because a late notification is a far more common reason for a declined claim than the condition itself.

Recovery and Prognosis

Outcome depends heavily on how quickly treatment starts, and this is the genuine reason for urgency rather than a scare tactic. Prompt, aggressive treatment of a first episode usually resolves the acute illness well. Delay allows more damage to the lymphatic vessels, and that damage is what determines whether the leg returns to normal and whether the problem comes back.

Published figures putting a precise percentage on full recovery do not exist for lymphangitis in the way they do for some conditions, and the confident-sounding numbers circulating online are not traceable to a source. What the literature and clinical experience support is a directional statement rather than a probability: earlier treatment means less permanent thickening and fewer recurrences.

A realistic timeline for an uncomplicated first episode:

• Days 1 to 3. Acute phase. Full medication, cold hosing, minimal controlled movement as directed. Fever should begin to fall.
• Days 4 to 7. Fever resolves, pain reduces, swelling starts to come down. Walking sessions lengthen.
• Days 8 to 14. Antibiotic course completes. Swelling continues to reduce. Limited turnout usually reintroduced.
• Weeks 3 to 6. Graded return to work, starting in walk. Bandaging tapered.
• Afterwards. Many horses keep a slightly thicker limb permanently. The aim shifts from cosmetic recovery to preventing episode two.

Where recovery is slow or movement remains restricted, equine physiotherapy is worth discussing with your vet.

Complications: Laminitis, Sepsis and Skin Loss

• Supporting-limb laminitis. The most important complication and the one owners underestimate. A horse carrying its weight on three legs for days is loading the opposite foot far beyond normal. Watch for shifting weight, a bounding digital pulse or heat in the opposite foot, and treat any of these as urgent.
• Sepsis. Infection escaping into the bloodstream. Uncommon but serious, and the reason a horse that becomes duller, more tachycardic or stops eating despite treatment needs same-day reassessment rather than another day of waiting.
• Skin necrosis and sloughing. In severe cases the skin over the swollen limb can die and separate, leaving large wounds that take months to heal and may go on to form proud flesh. Equine Veterinary Education carries a case report of a 16-year-old Thoroughbred mare whose hindlimb cellulitis and lymphangitis progressed to ischaemia of the lower limb, necrosis of the suspensory ligament branches and, on day ten, complete avulsion of the hoof capsule; she was euthanised (Duggan, Mair and Fews, 2021). That is one horse rather than a series, but it shows how far this end of the range can go.
• Permanent lymphatic damage. The commonest long-term outcome, and the driver of everything in the chronic case below.
• Secondary infection of damaged skin. Ongoing cracks in a chronically thickened limb become the entry point for the next episode, which is why skin care becomes a permanent job.

Feeding a Horse With Lymphangitis

This is one of the most common follow-up questions and one of the least well covered. There is no diet that treats lymphangitis, and nobody should be adjusting a feed bucket instead of ringing a vet. There are, however, four genuine connections between feeding and this condition.

1. Cut the hard feed when the work stops. This is the original Monday morning mechanism and it still applies. A horse on box rest or restricted movement does not need a working ration. Reduce concentrates to match the workload and keep forage in front of them.
2. Keep forage available. A horse standing in for two weeks with long gaps between feeds is at risk of gastric ulceration and of the behaviours that go with boredom. Ad-lib or near ad-lib forage, soaked if weight is a concern, is the sensible default.
3. Manage weight seriously. Excess body condition worsens limb oedema, increases the load on the opposite foot, and raises laminitis risk in a horse already standing awkwardly. If the horse is carrying too much, our guide to body condition scoring gives you an objective starting figure rather than an opinion.
4. Investigate the metabolic picture in recurrent cases. Where a horse keeps flaring, PPID and insulin dysregulation are worth testing for rather than assuming. Both are managed substantially through diet, and treating them addresses a cause rather than a symptom.

Any significant change to a sick horse’s diet should be discussed with your vet, particularly if the horse is on medication or has a history of laminitis.

Supplements, Herbal Remedies and Lymphatic Drainage

There is a substantial market in products promising lymphatic support, and owners of recurrent cases are an obvious target for it. A straight assessment:

• Oral supplements marketed for lymphatic drainage are not supported by good evidence in horses. That is not the same as saying they do harm, but they should not displace anything on the list that works, and they should never delay a vet call in an acute episode.
• Herbal preparations are in the same position, with the added caution that some plant products interact with prescribed medication. Tell your vet what the horse is receiving.
• Manual lymphatic drainage massage is more interesting. It is a recognised technique in human lymphoedema care and a number of qualified equine therapists offer it. Evidence in horses is limited, but the mechanism is plausible and owners of chronic cases often report benefit. Treat it as a reasonable adjunct for the established case, arranged through your vet, not as a treatment for an acute infection.
• Compression garments have the clearest rationale of anything in this section, for the same reason compression is standard in human lymphoedema.
• Magnetic products are frequently sold for swollen legs. Our review of magnet therapy for horses looks at what the evidence actually shows, and the important safety point is that warming kit must never be applied to an undiagnosed hot, swollen leg.

Preventing Recurrence

After a first episode the whole objective changes. These are the measures that genuinely reduce the frequency of flares, roughly in order of value:

1. Maximise turnout. Movement is the lymphatic pump, and this is the single most effective intervention available to you. Even a night in reliably refills a susceptible limb.
2. Inspect the legs daily. Every scratch, scab, crack and bite on the previously affected limb gets found and cleaned the same day. This is the intervention that stops the next infection getting in.
3. Prevent mud fever rigorously. Barrier products in wet conditions, dry standing, heels genuinely dry before turnout. Winter mud is the commonest route in.
4. Fly control through the summer. Repellents and fly boots reduce the bites that act as entry points.
5. Compression overnight where the horse must be stabled, removed for turnout.
6. Test for PPID in horses over about fifteen with recurrent infections. Undiagnosed Cushing’s is a frequent hidden driver, and treating it can substantially reduce flare frequency.
7. Keep vaccinations current and keep weight under control.
8. Agree an early-intervention plan with your vet. Knowing exactly what you will do, and who you will ring, at the first sign of heat saves hours that matter.

The Chronic Case and Chronic Progressive Lymphoedema

A horse with repeated episodes has moved into managing a permanent condition. The lymphatic valves no longer recover fully between flares, each episode adds thickening, and the threshold for the next one falls. These horses often still have useful working lives, but the management bar rises:

• The prevention list above stops being optional and becomes daily routine
• Workload may need shaping around what the limb tolerates
• An agreed plan for early intervention at the first sign of a flare
• Insurance exclusions become likely at renewal
• In a small minority of severe cases, welfare needs an honest conversation with your vet

Distinct from this, and often confused with it, is chronic progressive lymphoedema (CPL). CPL is a separate, apparently heritable disorder of the lymphatic system seen predominantly in heavy draught breeds, producing progressive swelling, thickened skin folds and chronic secondary infection of the lower legs. It is not caused by an episode of lymphangitis, although the two make each other worse and a CPL limb is highly prone to infection. Feather care is central to managing it. Our Clydesdale breed profile covers CPL in the context of the breeds most affected.

Front Legs, Sheaths and Other Sites

Front legs. Lymphangitis is far more common in a hind limb, but it does occur in a foreleg and the presentation is the same. Do not discount it because the swelling is at the front. If anything, a hot, painful, swollen foreleg warrants an even lower threshold for suspecting a septic joint or tendon sheath, or an infected hoof infection tracking upwards, all of which are more urgent still.

Sheath and udder swelling. Oedema of the sheath in geldings is common and usually reflects lack of movement rather than infection, often alongside filled hind legs. It is generally cool and painless and improves with turnout and exercise. Where sheath swelling is hot, painful, rapidly progressive or accompanied by a fever, it needs veterinary attention the same day.

Ventral oedema. Fluid along the belly midline has a different and broader differential, including cardiac, hepatic and protein-loss causes, and is not lymphangitis. It warrants investigation rather than a lymphatic label.

Frequently Asked Questions

Does lymphangitis go away in horses?

Not reliably on its own, and waiting to find out is the single most damaging thing an owner can do. Lymphangitis needs same-day veterinary treatment with antibiotics and anti-inflammatories. A horse may appear to improve briefly with cold hosing and then deteriorate. Untreated, the condition can progress to skin loss, sepsis or permanent lymphatic damage. Even with treatment, some residual thickening of the limb is common.

How long until lymphangitis is serious?

It is serious from the outset. There is no benign early window. The practical answer is that treatment started within the first day gives much the best chance of the leg returning to normal, and every additional day of delay increases the likelihood of permanent thickening and future recurrence. If you find a hot, painful, swollen leg with a fever, that is a same-day call, including out of hours.

What are the differences between horse cellulitis and lymphangitis?

Cellulitis is infection spreading diffusely through the subcutaneous tissue; lymphangitis is inflammation and infection tracking along the lymphatic vessels. In practice they overlap heavily and often coexist, and emergency treatment is the same. The signs that point towards lymphangitis are palpable cording up the limb, serum weeping through the skin, and above all a strong tendency to recur and to leave the limb permanently thickened. The distinction matters most for what happens after the acute episode, not for what you do in the first hour.

Is lymphangitis in horses contagious?

Sporadic lymphangitis, which is the common form, is not contagious and requires no isolation. Ulcerative lymphangitis warrants sensible hygiene, because the organism can be carried between horses on flies, bedding and shared equipment. Epizootic lymphangitis is genuinely contagious but does not occur in the UK or South Africa.

Can you ride a horse with lymphangitis?

No. During an acute episode the horse is too lame and too unwell, and exercise risks driving infection further up the limb. Controlled hand walking, once your vet advises it, is part of treatment and is entirely different from ridden work. Return to riding is gradual, typically starting in walk after lameness and swelling have resolved and building over several weeks.

What happens if you do not treat lymphangitis?

The infection continues to damage the lymphatic vessels, the swelling becomes established, and the limb may be left permanently thickened with impaired drainage. Severe untreated cases can progress to skin necrosis and sloughing, or to sepsis. There is also the secondary risk of laminitis in the opposite foot from prolonged weight shifting. Recovery becomes progressively less likely to be complete the longer treatment is delayed.

References and Further Reading

• MSD Veterinary Manual: Lymphangitis of Horses and Cattle
• Merck Veterinary Manual: Lymphangitis in Horses (owner-facing version)
• University of Kentucky Ag Equine Programs: Cutaneous Lymphangitis in Horses
• Duggan M, Mair T, Fews D. Equine limb cellulitis/lymphangitis resulting in distal limb ischaemia and avulsion of the hoof capsule. Equine Veterinary Education 2022;34(10). Published online 30 September 2021. doi:10.1111/eve.13570
• Braid H. Diagnosing and treating cellulitis in horses. In Practice 2024;46(10):536-540. doi:10.1002/inpr.495
• Braid HR, Ireland JL. A cross-sectional survey of the diagnosis and treatment of distal limb cellulitis in horses by veterinary surgeons in the United Kingdom. Equine Veterinary Education 2022;34(6). Published online 12 April 2021. doi:10.1111/eve.13484
• British Horse Society: health care and management
• British Horse Society: disease prevention (healthy temperature range 37.5-38.5C; temperature checks)

Lymphangitis punishes hesitation more than almost anything else you will meet on a yard. If you find a hot, painful, swollen leg, take a temperature, ring your vet, and start cold hosing while you wait. For the closely related conditions, see our guides to cellulitis in horses and mud fever.