Equine Metabolic Syndrome: Managing a Welfare Crisis in Leisure Horses

Equine metabolic syndrome (EMS) is a growing welfare problem in domestic horses and ponies, causing painful laminitis and requiring significant dietary management that conflicts with horses' natural grazing behaviour.

Key Facts

EMS affects an estimated 10-20% of leisure horses and ponies in developed countries, with native breeds most susceptible
The condition involves insulin dysregulation that causes episodic laminitis — inflammation of the sensitive tissues within the hoof
Laminitis pain is described by veterinary experts as among the most severe experienced by horses, equivalent to having a fractured leg
Horses with EMS must often be kept off pasture or muzzled — measures that restrict natural grazing behaviour significantly
The condition is strongly linked to dietary excess, particularly high-sugar grass in spring and autumn
Diagnostic testing including dynamic insulin testing is becoming more accessible and enables earlier intervention
Management involves restricted grazing, low-sugar forage, and exercise programs that can be challenging to implement for owners

Welfare Considerations

Horses with EMS face a difficult welfare trade-off: their metabolic condition requires severe restriction of the grazing behaviour that is central to equine wellbeing. Laminitis episodes cause intense, acute pain that can leave horses reluctant to move. Between episodes, dietary management can cause frustration and stereotypic behaviours in horses denied adequate forage time. The growing prevalence of EMS reflects the mismatch between ancestral equine diets and the energy-rich environments many leisure horses inhabit today, making proactive management and owner education essential welfare priorities.

What You Can Do

Have your horse or pony assessed for EMS risk if they are overweight or have had laminitis
Work with a vet to develop a low-sugar diet and appropriate exercise program for horses at risk
Use properly fitting grazing muzzles that allow some grazing rather than complete pasture restriction
Monitor body condition score regularly and aim for a score of 4-5 on a 9-point scale
Test hay and haylage for sugar content and choose low-sugar options for EMS-prone horses
Join owner support networks for EMS management to share evidence-based strategies
Avoid overfeeding leisure horses with hard feed or high-sugar supplements that exacerbate insulin dysregulation