Evaluation of genetic and metabolic predispositions and nutritional risk factors for pasture-associated laminitis in ponies.
Authors: Treiber, Kronfeld, Hess, Byrd, Splan, Staniar
Journal: Journal of the American Veterinary Medical Association
Summary
# Pasture-Associated Laminitis in Ponies: Identifying At-Risk Animals Through Metabolic Profiling Laminitis remains a significant welfare concern in ponies, yet predicting which animals will develop clinical disease has proven challenging. Treiber and colleagues conducted an observational cohort study of 160 ponies, using pedigree analysis and serial blood sampling to characterise the genetic and metabolic factors underpinning pasture-associated laminitis. They identified a prelaminitic metabolic syndrome defined by elevated body condition score, raised plasma triglyceride concentration, and insulin resistance (measured via reciprocal of the square root of insulin [RISQI] and modified insulin-to-glucose ratio [MIRG]), with meeting ≥3 of these criteria differentiating previously affected ponies from controls with 78% accuracy. Notably, metabolic profiling conducted in March predicted 11 of 13 clinical laminitis cases that manifested in May when spring pasture starch levels peaked, suggesting this syndrome represents a genuine preclinical risk state rather than simply a consequence of disease. For practitioners, these findings support the use of basal metabolic assessment and body condition evaluation as practical screening tools to identify susceptible ponies before laminitis develops, enabling targeted dietary intervention—particularly restriction of starch and soluble carbohydrate intake—rather than relying on reactive management of established disease.
Read the full abstract on PubMed
Practical Takeaways
- •Screen apparently healthy ponies with high body condition and family history for prelaminitic metabolic syndrome using blood markers (triglycerides, insulin, glucose) to identify at-risk individuals before clinical disease
- •Restrict dietary starch in ponies identified with metabolic syndrome markers, as high pasture starch concentration significantly increases clinical laminitis risk
- •Use basal blood insulin and glucose ratios (RISQI, MIRG) as practical preventive diagnostic tools to guide management decisions for individual ponies at risk of pasture laminitis
Key Findings
- •Laminitis inheritance pattern consistent with dominant major gene(s) with reduced penetrance
- •Prelaminitic metabolic syndrome defined by body condition, plasma triglyceride, RISQI, and MIRG predicted 78% of cases when ≥3 criteria met
- •March metabolic profiling predicted 11 of 13 clinical laminitis cases occurring in May during high pasture starch availability
- •Ponies with prelaminitic metabolic syndrome showed comparable metabolic abnormalities to human metabolic syndrome