FieldDxEquine metabolic syndromeClinical signs, differential diagnosis, treatment and prevention in horses.
Overview
A common endocrine condition of horses and ponies, a major risk factor for laminitis. Insulin dysregulation; the exact origin is incompletely understood but involves a combination of genetics, obesity, high-sugar/starch diets and inactivity.
Clinical signs
- Affected animals are typically obese, with an increased overall condition score and localized adiposity (cresty neck and tailhead region).
- Laminitis, both chronic and acute, is highly common.
- Hyperinsulinemia with normal blood glucose concentrations (insulin resistance) is the primary clinical pathologic finding.
- Associated signs include infertility, altered ovarian activity, and increased appetite.
- Laboratory evaluation reveals hypertriglyceridemia, increased serum concentrations of leptin, and arterial hypertension.
- Affected horses exhibit exaggerated glucose and insulin responses to an oral hexose load before developing true insulin resistance.
Predisposing factors
- Inability to properly metabolize dietary carbohydrate.
- The primary risk factor is insulin dysregulation.
Look-alikes to rule out
Treatment
The objective of treatment is to improve the insulin sensitivity of affected equids. This can be achieved by reducing the proportion of the body made up of fat through careful dietary control.
Drugs mentioned: Insulin
Prevention
1. Limit energy intake: forage at 1.25-1.5% of body mass as dry matter per day, cut to 1.0% for horses resistant to weight loss and monitored closely. 2. Exclude grain, cereal feeds, fruit, vegetables and treats; use forage with non-structural carbohydrate below 10%, soaking hay 1-2 hours if needed; do not feed haylage to horses with insulin dysregulation. 3.
Source
The Merck Veterinary Manual 11th Edition (Page 1006) 114.
A Textbook of the Diseases of Cattle, Horses, Sheep, Pigs and Goat by ELSEVIER — Equine Metabolic Syndrome
Journal of Veterinary Internal Medicine, Durham AE et al. (2019), via PubMed Central — ECEIM consensus statement on equine metabolic syndrome (accessed 2026-10-29)
Condensed and attributed, never reproduced whole. Open the full entry in the app.