Factsheets

Horses


Overview
Horses are part of an ever growing industry, with over 600,000 horses in the UK, 1.4 million riders and 5 million people with an active interest in the equine industry*. Most people acquire a horse out of choice, so if you make this decision you should think carefully before going ahead. A horse needs lots of love and care, including regular worming, vaccinations and dental care. Owning a horse is time consuming and can be costly; not only will you will need to consider where you will keep your horse, you must also consider the ongoing costs of owning a horse which include accommodation, bedding, feed and healthcare.

In the unlikely event that your horse goes missing it is going to be very difficult for anyone to know who it belongs to, unless your horse carries some form of permanent identification. It is wise to get your horse microchipped or freezemarked, this will avoid heartache in the long run, should your horse go missing or is stolen.

Horses are herd animals, and thrive on being together with other horses. Don’t forget that your horse will need somewhere to graze, a stable for warmth in the winter time, a constant supply of water, feeding daily and regular exercise. It can cost hundreds of pounds a month to care for a horse, including accommodation, food, veterinary care and insurance; there will be other costs, including buying tack and rugs and extra livery charges when you go on holiday.

Horses can live into their thirties, over this time your horse will need lots of care and attention. Being able to provide all of this will ensure you and your horse make the most of your time together.

* Research conducted in 2004 by the Henley Centre for DEFRA and the British Horse Industry Confederation.

Azoturia - 'Tying-up'

'Azoturia', 'tying-up', Monday morning disease and 'set-fast' are all alternative terms used to describe the phenomenon known in the veterinary profession as exertional rhabdomyolysis (ER).

In the past, when horses were used more frequently as working animals, the condition was usually seen following a day of rest and high concentrate feeding on a Sunday hence the term Monday morning disease.

What causes rhabdomyolysis?

ER is a complex disorder which has numerous causes. Horses suffering from rhabdomyolysis can be generally split into two categories: those which have an underlying muscular disorder, or those who have been physically over-exerted, ie have worked excessively hard.

Horses with a muscular disorder may suffer repeated bouts of rhabdomyolysis throughout their lives, whereas those who are over-exerted may only experience the condition once in a lifetime. Exercise is usually the trigger factor for ER in most cases. Overexertion causes damage to muscles, particularly of the hindlimbs and hindquarters. Tears in the junctions of myofilaments (an important component of muscle) have been found to be responsible for the muscle soreness characteristic of this disorder. Other possible causes of ER include:

  • Electrolyte imbalances.
  • Vitamin E and Selenium deficiency.
  • High-grain diets.

This picture shows a horse with rhabdomyolysis the horse is sweating and is reluctant to put the left hindlimb on the ground.

How do I know if my horse has rhabdomyolysis?

The predominant clinical sign of ER is a stiff, stilted gait and intense reluctance to move with visible sweating. Other clinical signs may include hardening and pain of the muscles over the gluteals (hindquarters), increased respiration and in severe cases the development of red urine (myoglobinuria) with possible collapse of the horse.

If you find your horse is experiencing any or a combination of the above clinical signs, veterinary attention must be sought immediately.

How is rhabdomyolysis diagnosed?

Your vet will perform a clinical examination. The history and presenting signs alone may be sufficient to reach a diagnosis. In most cases, a blood sample will be taken to determine if your horse has elevated muscle enzymes (creatine kinase (CK) and aspartate aminotransferase (AST)), which will confirm his/her suspicion of ER.

In some cases, your vet may perform further blood tests to determine kidney function and urine analysis. Repeat blood samples may be necessary at certain intervals to determine your horse's progress and response to treatment.

Can rhabdomyolysis be treated?

Treatment is largely dependent on the cause of ER. Generally, treatment involves strict box rest to allow the muscle damage to recover.

Anti-inflammatories may be administered to decrease muscular inflammation and provide pain relief. Keeping the horse hydrated is extremely important to the management of the condition.

In severe cases, intravenous fluid therapy may be required, and your vet may also advise adding electrolytes to the feed and/or water and decreasing the amount of concentrate (grain) feeding replacing this with a greater proportion of forage.

How can rhabdomyolysis be prevented?

  • Try keeping your horse at a constant level of fitness, to avoid over-exertion on any one particular day - it is much better to exercise your horse for an hour per day than for 6 hours on one day.
  • Always warm-up your horse adequately before asking it to perform strenuous activities. 
  • Avoid high levels of concentrate feeding, good quality forage such as hay and haylage are an essential part of your horse's diet.

If your horse does suffer from this condition seek advice from your vet regarding future management of your horse. A nutritionist may be able to advise you on how to improve your horse's diet.