Mouldable, thermoplastic, glue-on frog-supportive shoes change hoof kinetics in normal and obese Shetland ponies.

Abstract

BACKGROUND: Obesity and hyperinsulinaemia are frequently encountered in the equine population and risk factors for the development of laminitis. There are many options for hoof support that claim a beneficial effect, but often the scientific evidence is scarce. OBJECTIVES: To quantify the effect of frog-supportive shoes on hoof kinetics in normal and obese ponies. STUDY DESIGN: Controlled in vivo trial. METHODS: Ten Shetland mares (n = 10) with a normal (n = 5) or obese (n = 5) body condition were led over a dynamically calibrated pressure plate before (T0), immediately after (T1) and 72 h (T2) after application of the shoes. The following locomotor variables were measured: stance duration (StDur), vertical impulse (VI), peak vertical force (PVF), time to PVF and time from PVF to lift off. The hoof print was divided into a toe and heel region and the StDur toe-heel index was calculated. The toe-heel hoof balance curves of the vertical force were plotted throughout the stance phase. RESULTS: The VI and PVF increased significantly 72 h after application of the shoes, when compared with T0 and T1. The StDur toe-heel index and toe-heel balance curves were significantly different between the normal and obese ponies. These variables became more comparable between the groups after application of the frog-supportive shoes. MAIN LIMITATIONS: It would have been interesting to measure the effect of the shoe in patients with acute laminitis. However, this would have had major welfare implications. CONCLUSIONS: The obese ponies moved more carefully than the normal group, demonstrated by a decreased loading of the toe area. The data illustrate that the ponies became more comfortable 72 h after application of the shoes, with a pronounced effect in the obese group. Thus, these results suggest that frog-supportive shoes could be beneficial, especially for obese ponies.