Equine Herpesvirus (EHV)

EHV (Equine Herpesvirus) is a ‘special’ virus because it is endemic (everywhere!) Generally it causes mild respiratory symptoms, but it can turn occasionally nasty invading deeper into the neurological system (hence neurological effects). As many people have asked, vaccination does decrease the risk of EHV as it reduces the risk of viral shedding, improving herd immunity and meaning that there will be less chance of it being spread around between horses. The vaccine is truly effective for a short period of time however; if you want general cover then you can do an annual vaccination, however better protection will be provided by vaccinating every 6 months and if you are at high risk then you can do every 4 months. Pregnant mares should be vaccinated during the 5th, 7th and 9th month of pregnancy.

We advise our clients (especially those who are planning on competing, or who have breeding horses for example), to vaccinate. The primary vaccination can be given to any horse over 5 months old, and a second should be given 4-6 weeks later, followed by the booster every 4-6 months.

You can read more about the EHV outbreak earlier this year from the Animal Health Trust, along with some advice on monitoring horses that may be at risk.


Rainscald is common during the winter months with persistent rain – did you know it can be caused by the same bacteria as mud fever?

Rain scald causes dermatitis and is usually present along the horse’s topline (especially the loins) with the hair on affected areas resembling little paintbrushes. Scabs cause tufts of hair to become matted together, and when removed, they reveal sore skin underneath. Further secondary infection may result as the skin is weakened.

Affected areas need to be cleaned with Malaseb, diluted hibiscrub or similar and horses should be kept dry and free from mud and application of topical antibacterial will speed recovery. Remember that infection can be spread through contaminated grooming kits, so keep any brushes used for the affected horse separate. In severe cases a course of antibiotics may also be required.

Rainscald can sometimes be confused with ringworm (which is a fungal infection) so it is worth getting a proper diagnosis from your vet to ensure that your horse can be made comfortable, and so that you don’t waste time or money on the wrong treatment.


Tetanus, a bacterial disease that affect horses and also humans, is an often fatal bacterial toxin that affects the nervous system, causing progressively worsening muscle contractions. Usually associated with the spasms of the jaw and neck (hence its common name of “lockjaw”), the horse will be unable to eat or drink. But it is important to remember that all muscles can be affected; including those that control breathing. This is why death can occur due to respiratory failure (leading to cardiac arrest).

The bacteria are present in soil and droppings, therefore tetanus can be easily picked up from puncture wounds, open cuts, or the umbilici of foals. However, it can be easily prevented with a vaccine! This is why it should form part of your horse’s core vaccination schedule. Tetanus can be treated but reports state that 80% of horses die once recumbent, so if your horse is unvaccinated, prompt veterinary attention can mean the difference between life and death.


Strangles is endemic in the UK. It is an infectious bacterial disease that affects the upper respiratory tract. It usually causes:

  • high temperature
  • inappetance
  • nasal discharge
  • swollen glands and lymph nodes
  • abscesses, typically under the jaw.

It can be overlooked as ‘a bit of a cold’ but in time, infected horses can develop painful lymph node abscesses that often rupture. This makes it difficult for them to breath and swallow.
Another serious complication known as ‘bastard strangles’ can occur when the bacteria spreads and causes abscesses in other parts of the body (difficult to treat, this can often be fatal). Diagnosis is usually easy; blood tests can detect antibodies to strangles, and are useful for horses moving to a new yard, whereas guttural pouch lavage using an endoscope can be a quicker and more accurate test for most cases. At present, strangles vaccines have had limited success and high rates of vaccine reactions, so the best way to prevent the spread of strangles is good biosecurity measures.

Sweet itch

Its the time of year when we should start to consider sweet itch and helping our horses to deal with insect hypersensitivity.
Although this localised allergic reaction can be very uncomfortable for your horse or pony, there are various things that can be done to lessen the impact:

  • topical shampoos
  • stable horses at dawn and dusk when midges are most active.
  • insecticidal sprays
  • keep horse away from areas of standing water, woods and trees.
  • use special fly rugs/hoods.
  • Use fans in stables (midges are poor fliers!)
  • In some cases small doses of steroids may be appropriate.

If your horse is suffering from sweet itch and you’d like advice on management or other forms of treatment, do give us a call.


Laminitis can be extremely debilitating for horses. The laminae (that hold the pedal bone to the wall of the hoof) become inflamed and this can cause the pedal bone to rotate or drop.

There are conditions that can put a horse at risk of suffering laminitis such as EMS or Cushing’s (PPID) so it is important to consider that there may be underlying issues, rather than just putting it down to an excess of spring grass. If your horse or pony seems to get recurrent bouts of laminitis despite being on an appropriate dietary regime, it may be an idea to get a blood test done to screen for hormonal diseases that could be the culprit. The good news is that many cases can then be managed with medication and supportive shoes or pads when necessary.

Fused hocks in horses.

Have you heard of fused hocks in horses? These can either develop at a young age (juvenile osteochondral disease, as shown in the second x-ray image below), through degenerative joint disease, or sometimes through other trauma. Fused hocks tend to occur in the distal intertarsal and tarsometatarsal joints (the lower two joints in the hock). These joints have relatively low mobility.

La imagen puede contener: una o varias personas
A normal hock – note the space in the centre of the joint (the middle black line) compared to the image below.

How long does it take for hocks to fuse?

The process of bones fusing together is called ankylosis; in the hocks, the duration that this takes to complete can vary drastically between each individual horse.

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A fused hock – note the lack of space (no black line) in the centre of the joint.

Are fused hocks painful?

It is assumed that fused hocks are less painful, however the full fusion is a very slow progress. If hocks are not entirely fused, they have the potential to cause discomfort. Medication of the joints may enable the horse to continue to move without pain whilst the process is underway, however this should be monitored by the vet, including the use of diagnostic imaging, to determine progress. Once the hocks are fused, any discomfort or lameness tends to be eliminated, and the horse should usually be able to carry on in normal work.

There are some surgical options to fuse hocks, but they have to be considered very carefully.

Why flies can harm the eyes!

Warmer weather unfortunately can mean more pesky flies, and they can often irritate horses’ eyes. You may notice that your horse has swollen eyes or discharge (from one or both eyes). Likewise, the conjunctiva (the membranes or pink tissues surrounding the eye) may be red. Also, the white of the horse’s eye (sclera) may have more small blood vessels showing.

What can I do to help my horse’s eyes?

Using fly masks can prevent flies from irritating the eyes by stopping them from landing. There are many types available (some with ear covers to prevent flies biting the inside of the ears too.) Fly repellant may also be a good idea but take care not to get in the eyes. Further irritation could occur! Remember that if there are showers, it may not remain on the skin long enough to be effective. In some cases we may use antibiotics or steroids (or a combination of the two) to combat symptoms. Steroids can often be used to reduce inflammation and antibiotics deal with any bacterial infection.

It is also important to have the right treatment; human over-the-counter eye drops may not be suitable for treating infections. Also, if you are competing, eye drops containing steroids may not be appropriate!

What else should I look out for?

If your horse is scratching itself, then it could have another condition such as sweet itch. This may need investigating so that an appropriate management plan can be put in place. Flies may also be responsible for transmitting BPV which can cause sarcoids! Corneal ulcers can also develop if the horse rubs or scratches the eyes on either its legs or another surface. Again, this is where prompt veterinary attention is required to assess and treat the problem, thereby reducing the risk of any further issues.

Flies can irritate horses' eyes. A horse's eye with flies near it.

Equine Cushing’s Disease (PPID)

Equine Cushing's Disease, PPID - Dr. Emiliano Espinar Veterinary Surgeon

Equine Cushing’s Disease (PPID)VIDEO

Learn about Equine Cushing’s Disease in this video explaining the symptoms, cause, diagnosis and treatment of this condition.

Equine Cushing’s Disease (PPID)VIDEO

Learn about Equine Cushing’s Disease in this video explaining the symptoms, cause, diagnosis and treatment of this condition.

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