Horse Metabolic Syndrome: Seasonal Management

How to manage equine metabolic syndrome through the seasons, with particular attention to the highest-risk periods for laminitis.

Key Facts

Spring and autumn grass contains the highest levels of non-structural carbohydrates (NSC), creating peak laminitis risk for EMS horses
Frost stimulates NSC accumulation — grass grazed after a frosty morning can be dangerous for insulin-dysregulated horses
Late summer drought followed by rain also produces NSC surges as grass rapidly replenishes depleted reserves
Strip grazing extends access time while limiting total NSC intake, a practical compromise for horses that need some turnout
Dry lot turnout with access to low-NSC hay allows movement and enrichment without grass NSC exposure

Welfare Considerations

Seasonal management of EMS horses requires advance planning because the highest-risk periods correspond to times when owners most want to let horses enjoy spring grass. The welfare challenge is protecting horses from laminitis while not depriving them entirely of the outdoor experience that is itself welfare-important. Horses confined to bare yards for months develop boredom and frustration that are themselves welfare problems. Finding the balance — using strip grazing, dry lot turnout with appropriate hay, or carefully timed short grass sessions — requires understanding both the seasonal patterns of grass NSC content and the individual horse's specific insulin response.

What You Can Do

Restrict pasture access during spring and autumn peak NSC periods, particularly in the morning after cold nights
Develop a seasonal management plan with your vet before spring arrives rather than responding reactively to laminitis episodes
Test hay NSC content — many hay sources are unsuitable for EMS horses without soaking
Provide dry lot turnout with low-NSC hay as a welfare-preserving alternative to complete confinement
Install electric fencing for strip grazing — it is inexpensive and allows flexible management of grass access