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Equine metabolic syndrome: part 1

02 May 2024
15 mins read
Volume 8 · Issue 3
Figure 1. Photographic depiction of a horse with equine metabolic syndrome and regional adiposity. Notice the prominent crest along the dorsal aspect of the neck.
Figure 1. Photographic depiction of a horse with equine metabolic syndrome and regional adiposity. Notice the prominent crest along the dorsal aspect of the neck.


Both obesity and equine metabolic syndrome are being increasingly recognised. The underlying endocrine abnormality, insulin dysregulation, represents a high risk for endocrinopathic (hyperinsulinaemia-associated) laminitis. Early recognition and prompt treatment of the condition is crucial for the prevention of laminitis, a potentially severe disease that can have a fatal outcome. This article summarises current understanding of metabolic syndrome and its relationship to obesity. Current guidelines regarding early clinical recognition and corroborating diagnostic tests have been provided.

The risk of endocrinopathic laminitis is the pivotal reason that veterinarians should recognise horses affected with equine metabolic syndrome (Harris et al, 2020). Laminitis is often debilitating and, when severe, may lead to euthanasia. Therefore, laminitis should be prevented where possible through the institution of effective management as soon as equine metabolic syndrome is first identified. Diagnosis of equine metabolic syndrome is based on review of the medical history, management, physical examination and laboratory testing (Durham et al, 2019). Management approaches to reduce laminitis risk in horses with equine metabolic syndrome include exercise, nutritional advice, weight loss and, if needed, laminitis management. Pharmacological options are available for the treatment of severe or refractory cases, which will be discussed in Part 2 of this series.

The relationship between obesity and insulin dysregulation (in which obesity promotes insulin dysregulation), as has been well documented in the human medical context (Wondmkun, 2020). This is less clear in equine metabolic syndrome. However, degrees of obesity commonly alert veterinarians to consider equine meta-bolic syndrome. Obesity is also a risk factor for worsening laminitis by virtue of the additional physical weight force acting on the hoof–lamellar interface. Insulin is a pleiotropic hormone and one of its actions is to stimulate adipogenesis. Therefore, an obese phenotype may, in part, be promoted directly through elevated insulin influence, especially in the face of a positive energy balance.

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