Seasonal and annual influence on insulin and cortisol results from overnight dexamethasone suppression tests in normal ponies and ponies predisposed to laminitis

Abstract

Reasons for performing study: A simple, accurate test for identifying individual animals at increased risk of laminitis would aid prevention. Laminitis-prone ponies have a greater serum insulin response to dexamethasone administration than normal ponies in the summer, but the response during different seasons is unknown. Objective: To test the hypothesis that previously laminitic ponies have a greater insulin response to dexamethasone than normal ponies, which is present during all seasons. Study design: Prospective longitudinal study. Methods: Overnight dexamethasone suppression tests were performed on 7 normal ponies and 5 previously laminitic ponies in spring 2009 and 2010, summer 2008 an..