Equine Exertional Rhabdomyolysis: Part 2
By: Nicole Salo
Part 2 of 2
- In this second part to Equine Exertional Rhabdomyolysis, we’ll look at the treatments for getting a horse back into work that has suffered a Tying Up episode and the take home tips for preventing a Tying Up episode from happening.
How Equine Exertional Rhabdomyolysis Can Be Treated
Mild Cases:
A horse being treated for a mild case of ER should be given NSAIDs (non steroidal anti-inflammatory drugs) for several days along with plenty of rest and should have his grain or pellet rations withheld during this time. To promote blood flow to the muscles and help reduce muscle spasms, the horse may benefit from massage and heat therapy. As well, hand-walking the horse (if he is comfortable and willing to do so) will also help to improve the blood circulation. Turn-out in a safe area will also encourage movement. After a mild bout with Tying Up the horse should be moving normally within 12-36hrs after the episode.
Severe Cases:
During severe cases of Tying Up a horse may need fluids if his urine is discoloured, the horse is dehydrated or if he is receiving NSAIDs. Extra fluids will increase urine production aiding in flushing out the excess, and potentially harmful, myoglobin from the kidneys and will reduce NSAID-induced kidney damage. Fluids should be given until the urine is clear in colour, this can take several hours up to a few days.
Vasodilators (drugs used to relax smooth muscle in order for blood vessels to widen and reduce blood pressure) can be used in order to help promote more blood flow to the muscles. Owners should only give vasodilators under the prescription and guidance of a veterinarian, as it can cause the horse’s blood pressure to drop too low resulting in collapse in a severely dehydrated horse.
Vitamin E may be given as it is an anti-oxidant, to prevent further cell degeneration in the damaged muscles. Vitamin E products must also be given with care, as some Vitamin E products may contain selenium. Selenium is a trace mineral that can be toxic if over fed.
Bicarbonates (major elements which help buffer lactic acid generated during exercise and, also help to reduce the acidity of dietary components) will not help buffer lactic acid in the bloodstream, as it only targets lactic acid buildup in affected muscle mass.
Horses showing signs of severe Tying Up should not be moved until they are comfortable enough to do so willingly, unless the horse’s stall is near by and the horse can be moved safely. It may take several days for the horse to become comfortable enough to move around without pain, at this point the horse should be hand-walked a couple times a day or turned out in a safe paddock for a few hours to encourage blood flow to the muscles through movement.
Returning Exertional Rhabdomyolysis Horses Back To Work
Horses may be returned to work if they are no longer showing signs of Tying Up and are no longer taking NSAIDs, which may hide the signs of Tying Up. If the horse is reluctant to move, is still taking NSAIDs, or blood tests show that CPK and AST levels have not returned to normal, the horse should not be asked to exercise or be returned to work. Horses coming back to work should be exercised at the walk and trot for 10-15min a day over several days, increasing as the horse becomes more willing to move freely. This may take up to several weeks if the horse’s last bout with ER was a severe one. It is recommended that the horse not be pushed into working, as this may result in a relapse of Tying Up. It is best to take it easy at this time, as each time a horse relapses with ER; the case can become more and more severe resulting in permanent muscle damage. As well, at this time the horse should be slowly reintroduced to his grain diet if needed.
The prognosis is excellent for horses that have experienced a mild episode of Tying Up, returning to their former level of competition successfully. Your veterinarian’s recommendations should be followed closely to help prevent future episodes of Tying Up. However, horses that have experienced severe Tying Up may be less likely to return to their former level of competition if the muscle degeneration is significant (fibrosis may have occurred leaving the horse with loss of muscle function). Prognosis is guarded for horses who have suffered severe ER.
Take Home Tips on Preventing Equine Exertional Rhabdomyolysis
- Feed a high fiber diet that is low in carbohydrates, sugar and starches
- Feed a balanced diet, by having your horse’s hay analyzed you will better know which feed additives and supplements your horse does or does not need
- Use oils such as Soya or corn oil rather than cereal grains for added calories
- Feed concentrates after a work out, rather than before it
- Reduce concentrates when the horse is having time off, even if it is only for one day
- Feed salt and electrolytes when necessary to working horses
- Adding potassium, *selenium and Vitamin E to the diet may also be beneficial *Caution: selenium is toxic if overfed, only add selenium to the diet if the horse is in need of supplementation
- Allow daily turn-out, especially when the horse is not being exercised, this will also help to reduce stress
- Warm up and cool down sufficiently, this means a 10min walk and trot for warm ups and a 10min walk for cool downs
- Allow the horse a long rein during warm ups to reduce excitement, therefore reducing stress
- If there is sign of a viral infection on the farm, reduce the horse’s workload promptly
While there is no for sure answer why Equine Exertional Rhabdomyolysis occurs, it is believed that diet plays a major role in the management and prevention of Tying Up. Susceptible horses should be managed on a balanced fiber based diet, which is low in starch (cereal grains), sugar and carbohydrates.
Nicole Salo has a solid foundation as an equine entrepreneur in the horse industry with experience in various parts of the industry, including: training, breeding, management, social media and online content. Nicole currently holds an Equine Science Certificate and Diploma in Equine Studies through the University of Guelph while aspiring to finish her Certificate in Equine Business Management.
