Conditions & Illnesses



Pinworms are a common topic for questions from our clients.  They are not harmful to your horse but their lifecycle can cause significant irritation.

Pinworms, Oxyuris equi, are small roundworms that live in your horses large intestine.  The females migrate from here to the anus where they lay their eggs on the skin surrounding it. It is these sticky eggs that irritate your horse and can cause them to rub and itch around the base of their tail and anus.  These eggs can hatch and be infective within a few days or drop off and remain dormant for months in the environment.

How do I know if my horse has pinworms

Unlike many other worms, pinworms cannot be detected using a faecal egg count.

  • Your horse may be itchy around their tail base and anus
  • Eggs are sometimes visible around the anus as a yellow, sticky mass.
  • Your vet can perform and adhesive tape test and identify the pinworm eggs with a microscope.

How do I treat for pinworms?

Pinworms are sensitive to the same drugs that you would use in a regular worming program. Ivermectin, moxidectin, fenbendazole and pyrantel are all usually effective.  If you are treating for pinworm you should also wash your horses perineal region (anus and area under their tail) regularly to remove any existing eggs.


Mud Fever

Mud Fever

It’s that time of year where mud fever is a problem many horse owners will be faced with.  Mud fever or pastern dermatitis is a common bacterial infection usually seen on the heel bulbs and back of the pastern.  There is usually a dominant bacteria such as Dermatophilus congolensis but the condition is frequently a complex mix of different bacterial and fungal species.

What does mud fever look like?

  • Matted hair with crusting and scabs
  • Small, ulcerated, moist lesions
  • Thick, creamy, yellow/white/green discharge
  • Deep cracks in the skin
  • Hair loss (alopecia)
  • Heat, pain, swelling with possible associated lameness

What can cause mud fever?

  • Soil type – some soils can predispose horses to mud fever so outbreaks on yards can be common
  • Prolonged damp – either in the field or from deep, dirty, wet bedding.
  • Feathering – heavy feathering can predispose horses to infestation with Chorioptes mites (feather mites) which can increase the risk of mud fever.
  • Trauma to the skin can provide an entry point for the bacteria
  • White limbs have been suggested to be more susceptible to mud fever

How do you treat mud fever?

  1. Clip the affected area – remove the hair so the skin can dry out. Removing feathers also allows you to better access the skin to treat and inspect it.
  2. Wash with an antimicrobial and antibacterial shampoo or scrub, such as Malaseb or dilute hibiscrub then rinse and dry thoroughly. Continue once daily for 1 week.
  3. Gentle removal of softened scabs can help to decontaminate the area. Do not remove dry or well adhered scabs as this can leave an open wound in the skin and predispose to further infection.
  4. Apply an antibacterial cream such as Flamazine to the affected area twice daily. Our own antibiotic Mud Fever solution is very effective at treating even the worst of mud fever.

When should I call my vet?

  • If your horse becomes lame
  • The condition continues to get worse or does not show any sign of improvement
  • There is swelling of the area or leg
  • You have any other worries

 Please don’t hesitate to call us today if you have any concerns or questions regarding the health of your horse

Eye Injuries

The prominent location of your horses eyes leave them very exposed to injury. Even minor damage to the eye can worsen rapidly and put their sight at risk in as quickly as a few hours to days in some cases. Combined with the fact that injury, infection or inflammation of the eye can be extremely painful for your horse it important to identify injury and seek veterinary advice as soon as possible.

Signs of a Painful Eye

  • Excessive tear production
  • Squinting or closing of the eye
  • Swelling/ redness
  • Discolouration of the eye
  • Avoiding bright light
  • Constriction of the pupil
  • Discharge from the eye

What to do

If you suspect your horse has an injured eye:

  • Move them to a darkened stable
  • Remove any objects that they could rub their eye on (rugs, tack etc)
  • Call your vet

Choke – Oesophageal Obstruction

Choke – oesophageal obstruction

What is choke?

The term choke can be misleading. Choke in horses refers to an obstruction of the oesophagus, not the trachea as in humans.  This means while choking your horse will be able to breathe, despite being in distress.

What causes choke?

  • Poor dental health
  • Horses with dental abnormalities such as missing teeth, malocclusions or sharp points are unable to chew effectively. This puts them at a far higher risk of choking compared to those that have good dental health.
  • Bolting feed
  • Some horses eat too fast and do not chew properly leading to choke. This can be avoided by placing large stones in with their hard feed which they must eat around, slowing them down.
  • Dry food
  • Dry food is often harder for your horse to swallow than damp or wet food. This cause of choke is easily avoided by slightly wetting your horses feed. This is very important for sugar beet which must be properly soaked before feeding.
  • Foreign objects
  • Occasionally your horse may eat something it shouldn’t, such as a piece of wood, which could get stuck in their oesophagus

Signs of choke:

  • Distress
  • Coughing
  • Not interested in food.
  • Difficulty swallowing.
  • Head and neck extended in a downwards position.
  • Nasal discharge
  • Saliva drooling from the mouth

What to do if your horse is choking

You should remove any remaining food from your horse and call us for advice.

Your vet will likely sedate your horse and give them some anti-inflammatory medication.  This will help your horse relax and may release the blockage.

Some obstructions require your vet to pass a stomach tube through your horse’s nose. This allows them to lavage the blockage with water to remove it through the tube, this can be a time consuming process if the blockage is large.




Equine atypical myopathy (EAM) is a serious potentially life threatening condition caused by eating Sycamore seeds or possibly leaves. Incidences tend to occur in autumn and in the spring following large autumnal outbreaks. Horses that develop EAM are usually kept on sparse pastures with an accumulation of dead leaves or wood present. There is often no supplementary feeding with hay or hard feed. Outbreaks frequently occur following a period of wet, windy or cold weather coinciding with when large numbers of seeds are falling. The amount of toxin within the seed is variable although the levels are thought to increase during the autumn months. It isn’t known how many seeds need to be eaten for a horse to become sick. It is likely that some horses are more susceptible than others, young horses and foals seem to be particularly susceptible. The disease results in muscle damage, affecting the muscles which enable a horse to stand, breathing muscles and the heart muscle. Due to the muscle damage, urine of affected horses becomes a dark red colour due to excretion of pigment from the affected muscles.

What are the signs?

Early signs of the disease include lethargy, dullness or mild weakness. These signs usually progress quickly to stiffness, muscle tremors, extreme weakness and increased periods of lying down. In severe cases the horse may be found lying down and unable to stand. Owners may be concerned their horse has colic. Some horses may be found standing rooted to the spot, with a low head carriage, vocalising (whinnying) and head nodding. If you suspect your horse has atypical myopathy phone the practice as a matter of urgency.


The physical examination and grazing history will often give a strong index of suspicion for the disease. A urine sample can be obtained and visually confirms ‘dark red urine’, laboratory testing can confirm the presence of muscle protein in the urine. Diagnosis can be confirmed by checking the blood to test and measure the muscle enzymes. Kidney parameters may also be elevated. If one horse is suspected to be showing signs of EAM the remaining field companions should be removed from the pasture, examined and the blood tested for early signs of the disease.


Horses treated for EAM require intensive 24/7 nursing care including intravenous fluid therapy to restore circulation and protect the kidneys from the damaging effects of the muscle protein.  EAM cases are often very painful and therefore require painkillers and supplementary vitamins and minerals may also be beneficial. Cases may get worse before they get better so if transport of the horse is possible early referral to a hospital is usually advisable. Those horses that do recover usually make a full recovery and return to work with no-long term effects of the disease.


The Sycamore seeds and to come extent the leaves are the only known source of the toxin although other sources may be elsewhere. Fence off any Sycamore trees or areas where seeds have fallen. Cases of EAM that arise in the spring are thought to be associated with ingestion of the seedlings therefore where possible remove seeds from the pasture. Supplementary feeding with hay or haylage will discourage horses from eating the seeds. Turning horses out for shorter periods of time where possible.

Due to the variability of the toxin levels in the seeds and to a lesser extent the leaves, cases of EAM have been seen in horses that may have grazed the same pasture previously with no signs of the disease. The introduction of a new herd mate may result in the new herd mate becoming affected despite other horses having shown no signs of the disease. Therefore it is always worth following the prevention steps above to avoid cases of EAM.

Phoebe Parker BVetmed MRCVS

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