Is your horse struggling to lose weight this summer? Equine Metabolic Syndrome, known as EMS, could be one reason why slimming down seems an impossible task for your equine. Here is some helpful information on EMS and why it is important to manage.
What is EMS?
‘EMS’ or Equine Metabolic Syndrome is a hormonal condition where insulin is not regulated appropriately and horses become insulin resistant, similar to Type II diabetes in people. EMS is most common in overweight horses although all horse can be affected; it poses an increased risk for laminitis.
What are the signs of EMS?
Signs of EMS include:
- Abnormal or regional fat deposits including crest, behind the shoulder, tail ahead and above the eyes
- Difficulty losing weight
- Recurring episodes of laminitis
- Lethargy (lack of energy)
- Increased drinking and urination
- Uncommonly infertility in mares
How is EMS diagnosed?
EMS is diagnosed on a blood test.
A blood sample taken from your horse will be analysed to look at the levels of insulin, adiponectin and glucose. These markers are indicative of EMS.
In some cases, an oral glucose challenge test is required to identify cases of EMS.
How is EMS treated?
Weight management is mainstay in the treatment and prevention of horses with EMS, which can reduce the risk of chronic, recurrent laminitis.
Diet
- Horses should eat 2% of their body weight in food daily (i.e. on a hay only diet this would be 10kg of hay for a 500kg horse).
- For weight loss, this can be reduced to 1.5% of body weight in a 24-hour period. It is important to also include weight of hard feed and grass in these calculations.
- Soaking hay will reduce the sugars and calorie content further. If you are weighing your horse’s hay, then weigh when dry before soaking for 6-12hrs in cold or 1-2 hours in warm water.
- Forage analysis can be useful to learn the nutritional value and calorie content of your hay.
- Up to one third of your horse’s forage ration can be substituted with straw, which is low in calories but ensures continued chewing and gut fill. Straw should be introduced slowly as it can increase the risk of impaction colic.
- Grazing restriction is best done using a track system, grazing muzzle or strip grazing. Time-based restrictions are often ineffective as ponies can eat their daily allowance in as little as four hours! Turnout remains important as the physical activity is of big benefit.
- Avoid giving your horse high sugar treats or hard feed as these are often high in calories. However, a low-calorie balancer is worthwhile to guarantee horses and ponies are still getting all the required vitamins and minerals whilst on a restricted diet. Splitting the balancer into frequent smaller meals can reduce the insulin spike associated with hard feed and is sometimes necessary for severely affected individuals.
- If needing to give medications or supplements use molasses-free foods.
Exercise
- Exercise is very important in weight loss. If your horse or pony has laminitis, please consult with your vet prior to starting an exercise programme.
- Exercise programmes should gradually increase in line with your horse’s fitness; 20 minutes of trot work a day has been shown to improve insulin sensitivity.
Alongside weight management there are medications which can be prescribed for EMS in horses. Medication does not replace strict management of these horses but is used alongside to aid in initial weight loss or when weight loss resistance is encountered.
- Ertugliflozin (& other SGL2 inhibitors) – This is the newest group of available drugs which work by encouraging glucose excretion in urine. The lower blood glucose reduces the insulin level in blood and aids in weight loss.
- Levothyroxine – This drug increases metabolic rate to aid in weight loss.
- Metformin – Used in type II diabetes in people, this drug can also be helpful in EMS cases. It is not absorbed as well by the gut in horses as it is in people, meaning this drug is not as commonly prescribed now there are newer drugs available.
Danielle Bowles BVMedSci (Hons) BVM BVS MRCVS
