Figure 1.

Scatter plots of individual horse data (n = 49) showing the relationship between oral sugar test derived indices of β‐cell response: Peak_INS (A), AUC_{INS ‐180} (B), INS_INDEX (C), AUC_{INS / GLU ‐30} (D), AUC_{INS / GLU ‐120} (E), and AUC_{INS / GLU ‐180} (F) versus the mean insulin‐dependent glucose disposal rate (M), in horses with normal insulin regulation (NIR, black circle) and insulin dysregulation (ID with previous history of laminitis, orange downward pointing triangle; ID without previous history of laminitis, blue upward pointing triangle). A solid line (line of best fit) represents a rectangular hyperbolic curve fitted to the data. The curve is based on the function (y = constant × 1/x), where the constant = disposition index. Data that fulfill the statistical criteria of a rectangular hyperbolic curve have the equation in the figure (C, D and E). Three of the horses had a delayed early glucose and/or insulin responses during OST, resulting in missing data for INS_INDEX and AUC_{INS / GLU ‐30}.