Equine Metabolic Syndrome
Written by Mishel Metcalf for Hi Form Australia 2026
The term Equine Metabolic Syndrome is currently used to describe horses and ponies with an insulin-resistant phenotype linked with laminitis susceptibility. Pituitary Pars Intermedia Disorder (Cushing’s Disease) is also associated with EMS.
Research in Australian studies has shown numbers as high as 24% of horses and ponies in SE Australia are affected by EMS. Equine Metabolic Syndrome is a massive problem that needs addressing. Further research is required to understand genetic and metabolic susceptibility.
Nutritional factors that can contribute to EMS are
Obesity
Poor diet – grain or starch overload
The owner is underestimating the horse's body condition
Over feeding
Inappropriate & unbalanced diets
Excessive exposure to NSC pastures
Some symptoms associated with EMS include
Insulin dysregulation, which requires a blood test to be confirmed
Laminitis – a painful hoof condition that can often be career-ending for performance horses
Obesity – horses with EMS typically start as being overweight
Swelling above the eyes
Unusual fat deposits
Additional thirst and water intake
Poor performance and lethargy
Key facts for helping a horse with diagnosed EMS.
Calculate the horse's body weight and condition score using tools available, such as weight tape and online condition scoring charts. Formulate a ration based on appropriate feeding for age /condition/ weight loss if required.
Discuss low NSC feeding options.
· Hay – should be feed tested and under 10% NSC. Certain types of pasture are very high in sugar and starch, such as Rye, & clovers. These should be avoided; offer the customer Teff or tested meadow hay. The test is important because even teff can be high in sugar when grown in certain conditions. Soaking the hay then rinsing it is a practical tool for removing sugar.
· Hard Feeds – As most horses with EMS will have some time in confinement, hard feeds become essential. All hard feeds should be natural, full of fibre and not include anything that will put added pressure on metabolism.
C Choose a high fibre cube such as Alphafibre
o High fibre
o Complete feed with daily vitamin and mineral supplement included
o Supports gut health
o Low in starch and sugar
o No added by products, no fillers, no preservatives
o Contains lucerne hay that is tested to be under 10% NSC prior to each batch
o EMS & Laminitis safe
· Treatment Products – Vets will often prescribe long-term drug treatments for horses with EMS. Another route of therapy, Equimetabalance is formulated to assist in the management of EMS, working to help regulate metabolism and stabilise insulin function. Equimetabalance has had success in halting the need for long-term drug therapy.
