Changes in Hoof Shape During a Seven-Week Period When Horses Were Shod Versus Barefoot.

Sara R Malone,Helen M S Davies

doi:10.3390/ani9121017

Abstract

Simple SummaryThis study explored changes in hoof shape related to the application of horseshoes. Past research has indicated that horse hooves change shape in response to gallop exercise, so this study sought to separate the changes due to exercise from changes due to wearing horseshoes. Amongst the most important findings were that proximal (coronary band) hoof circumference decreased more when horses were shod compared to barefoot, and hoof angle decreased when horses were shod but increased when horses were barefoot over a seven-week interval. A better understanding of the relationship between hoof shape and shoeing could help improve horse management practices. This crossover study tested the hypothesis that hoof shape would differ after a seven-week period of horses (n = 11) wearing shoes versus barefoot. An ANOVA appropriate to a crossover design was used to assess the differences in the change in hoof shape over the seven-week period and significance was set at p < 0.05. Results are displayed as the mean difference for horses when shod versus barefoot ± the SEM for the left (L) and right (R) front hooves. Proximal hoof circumference (PHC) decreased when horses were shod and barefoot, but this decrease was greater when horses were shod (L −0.65 ± 0.16 cm; p = 0.0026; R −0.78 ± 0.13 cm; p = 0.0002). Hoof angle increased slightly when horses were barefoot and decreased when they were shod (L −1.70 ± 0.31°; p = 0.0004; R −1.84 ± 0.54°; p = 0.0079). Sole length decreased more when horses were barefoot, but this was only significant for the right fore (R 5.07 ± 1.06 mm; p = 0.0010). Solar circumference increased when horses were barefoot but decreased when shod (L −1.19 ± 0.41 cm; p = 0.0182; R −1.50 ± 0.31 cm; p = 0.0010). This is the first study to show a significantly lower PHC when horses were shod compared to barefoot. The study suggests that shod horses may benefit from a shorter shoeing interval to help mitigate the changes in hoof angle.

Highlights

There is little doubt amongst equine industry stakeholders that hoof health is integral to the soundness of a horse
Racehorses with long toes and low heels are more likely to suffer musculoskeletal failure while racing [4] and horses that suffer catastrophic lower limb injuries during racing have a higher incidence of underrun heels [5]. It is unclear if hoof conformation is a direct cause of injury, or if injury occurs in association with other biomechanical, physiological or neurological complications
This study demonstrates a significant effect of shoeing on hoof shape

Summary

Introduction

There is little doubt amongst equine industry stakeholders that hoof health is integral to the soundness of a horse. The shape (or conformation) of the hoof may have serious implications for the soundness of the animal and hoof problems are a major cause of lameness in the horse [1,2,3]. Racehorses with long toes and low heels are more likely to suffer musculoskeletal failure while racing [4] and horses that suffer catastrophic lower limb injuries during racing have a higher incidence of underrun heels [5]. It is unclear if hoof conformation is a direct (mechanical) cause of injury, or if injury occurs in association with other biomechanical, physiological or neurological complications.

Methods

Discussion

Conclusion