Equine Metabolic Syndrome (EMS)
Insulin is a hormone that regulates the metabolism of glucose in horses. It is produced by the pancreas and is necessary for the proper functioning of the body's cells, tissues, and organs.
What is Equine Metabolic Syndrome?
Equine Metabolic Syndrome (EMS) is a common metabolic condition characterised by an inability to regulate blood glucose levels as a result of insulin resistance. It is very similar to type 2 diabetes that can be seen in humans. Complications of EMS include increased fat deposition, inability to lose weight, blood clotting disorders and a weakened immune system. Mares with EMS are put at a greater risk of infertility.
EMS and Cushing’s Disease
Horses with EMS are more likely to develop Cushing’s disease, a condition in which the pituitary gland produces too much adrenocorticotropic hormone. This causes excessive hair growth, chronic infections and other unpleasant symptoms.
How do horses develop EMS?
Any horse or pony can develop EMS however those that are overweight, obese or fed a high sugar and starch diet are put at a greater risk.
Symptoms of EMS include:
- Inability to lose weight
- Abnormal fat deposits on the shoulders and hind quarters
- Cresty neck
- Excessive thirst
- Increased urination
- Frequent episodes of laminitis
A diagnosis of EMS can be confirmed through blood testing. A vet will take a blood sample to measure levels of blood glucose and insulin. High levels of these are a clear indication of EMS.
Is there a cure for EMS?
Unfortunately there is no cure for EMS, however measures can be taken to manage symptoms and reduce the severity of clinical signs. In some cases, veterinary drugs may be prescribed to help regulate insulin levels and manage symptoms of EMS.
Managing Symptoms of EMS
It is important that horses and ponies with EMS are fed a low sugar and low starch diet, as this will minimise the risk of further weight gain and developing laminitis.
Concentrate feeds that are high in starch and sugar should be removed from the diet and replaced with a suitable fibre based alternative. Forage can also be soaked to reduce nutrient content. It is important that horses are not starved as a quick means of losing weight, as this can lead to other serious problems. If you have any concerns about your horse’s diet contact a vet or nutritionist who will be able to advise.
If turned out in the summer months it is important that horses with EMS have their grazing intake monitored, particularly when grass is lush, as this is when its sugar content will be at its highest. Grazing during daylight hours should also be avoided as this is when the grass sugar content is at its highest.
Horses who have developed laminitis may also require additional supportive care to manage the painful symptoms associated with the condition. In more severe cases of laminitis, remedial shoeing may be necessary to alleviate pain and maintain soundness.
Controlled weight loss is also essential in the management of EMS. Exercise may be difficult for horses with EMS, particularly if they have already developed laminitis as a result. A good exercise programme will start with low intensity exercise that is gradually increased over a period of several weeks, as this minimises the strain that is put on the horse’s body. Gradual weight loss is also important, as rapid weight loss can lead to a condition called hyperlipemia which can be fatal.
How to measure your horse’s weight
It is important that owners regularly monitor their horse's weight and condition to ensure that they remain in optimum condition and to minimise the risk of developing EMS. Weight can be monitored through use of a weigh bridge or a weigh tape. Recording your horse’s weight will highlight any abnormal patterns that need to be addressed.
Regular body condition scoring is also recommended as this will indicate any abnormalities in fat deposition, one of the main symptoms of EMS.