• Menzies-Gow NJ, Knowles EJ, Rogers I, et al. Validity and application of immunoturbidimetric and enzyme-linked immunosorbent assays for the measurement of adiponectin concentration in ponies. Equine Vet J 2019;51:33-37.
• Menzies-Gow NJ, Harris PA, Elliott J. Prospective cohort study evaluating risk factors for the development of pasture-associated laminitis in the United Kingdom. Equine Vet J 2017;49:300-306.
• Knowles EJ, Elliott J, Harris PA, et al. Predictors of laminitis development in a cohort of nonlaminitic ponies. Equine Vet J 2023;55:12-23.
• Elliott J, Bailey SR. Consequences of adiponectin deficiency: Can they be related to the pathophysiology of laminitis? Equine Vet J 2023;55:346-349.

• Although dynamic testing (OST or post-feed) could be performed, the combination of normal adiponectin and normal insulin on a non-fasted resting sample is a strong indication that the animal is metabolically healthy and has a low risk for laminitis.  It may still be worthwhile considering continued annual screening depending on breed, age, body condition and other factors.

• This is strongly supportive of ID/EMS, even without dynamic testing.
• In all cases, feed and management changes should be initiated.
• In cases where the resting insulin is only mildly increased (<50 uIU/mL) further testing with OST or post-prandial insulin testing (2 hours post hay/grain/pasture access, 1 hour post ration balancer) is indicated.
• In severely hyperinsulinemic animals (>100 uIU/ml) it is ideal to first confirm the hyperinsulinemia on at least one more sample prior to considering initiating pharmaceutical therapy to help reduce blood insulin.

• This result may be best viewed as a warning that the horse is more likely to become hyperinsulinemic at other times (especially in response to feed/pasture high in non-structural carbohydrate).  Although adiponectin is very stable (not affected by feed/ stress) insulin is very dynamic, so a one-off sample is often not representative.
  
• A low adiponectin may also make a horse or pony more susceptible to laminitis as a result of high insulin (based on evidence from pony studies, low adiponectin is an independent risk factor for laminitis - independent of ID status).  Similar to humans with metabolic syndrome, adiponectin may be somewhat protective against the deleterious effects of EMS/ID in horses and ponies.
  
• In these cases further insulin testing is indicated: OST or post-prandial insulin (2 hours post hay/grain/pasture access, 1 hour post ration balancer).  This will tell you how worried you need to be about insulin under the current management conditions – and how concerned you need to be if there is pasture access particularly in spring/summer. If this further testing is normal then there is no need to act further, but regular monitoring (at least yearly) is indicated.  If OST/post-feed insulin is high then consider feed/management changes etc. to address it.

• A mild increase in insulin (<50uIU/ml) with normal adiponectin warrants further insulin testing : OST or post-prandial insulin (2 hours post hay/grain/pasture access, 1 hour post ration balancer) to guide further decision making. It is important to note that this result may be due to stress/transport/sedation or feed access prior to sampling causing a transient mild increase in insulin - insulin is dynamic and readily affected by these factors, whereas adiponectin is much more stable.
• In severely hyperinsulinemic animals (>100 uIU/ml), regardless of adiponectin result, management/feed change and medication to help control insulin should be considered immediately - it is ideal to first confirm the hyperinsulinemia on at least one more sample prior to initiating therapy. Severe hyperinsulinemia with normal adiponectin is an extremely rare combination.

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Management including diet, weight loss, exercise, and medication can improve adiponectin concentration over time, but in our experience increases in adiponectin can take several months. Counter-intuitively, short term decreases in adiponectin commonly occur in the initial weeks to months after institution of appropriate dietary control, weight loss, and confinement (in laminitic cases) and this may reflect decreases in fat and/or muscle mass in the short term. Increases in adiponectin may take longer, therefore repeat measurement every 6-12 months as part of a screening program is recommended, however serial monitoring over weeks/months in newly identified ID/laminitis cases may not be beneficial.