Comparison of Six Different Methods for Measuring the Equine Hoof and Recording of its Three-Dimensional Conformation.

ABSTRACT

Different measuring techniques have been used to objectify the classification of hoof shape. The MicroScribe is a novel tool that might prove useful for measuring hooves without prior reconstruction or compensation of projection artefacts. The aim of this study was to compare biometric data of the equine hoof collected by the MicroScribe tool and measurements collected directly from hooves, scaled photographs and radiographs, from photogrammetry models and computed tomography datasets. The suitability of MicroScribe generated data to differentiate individual hoof conformations was tested. A total of 62 measures were recorded from 16 forehooves. 21 linear and nine angular measures were collected by at least four methods each, and evaluated further by analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA). Ratios and differences of these measures were calculated as suitable for the definition of hoof shapes and analysed as well. Absolute equivalency of methods was detected for five linear and none of the angular measurements. The precision of the tested measurement methods was comparable. In some cases, different methods measure different structures. Radiographs tended to overestimate, while computed tomography slides to underestimate distances. Photogrammetry and scaled photographs were less suitable for measuring hoof angles. The MicroScribe tool can readily be used for hoof measurements. Its values for linear measures showed good equivalency with other methods based on real hooves. For angular measurements, the uneven hoof surface might introduce imprecision. Not all hoof conformations could be detected based on measuring results alone. Diagnosis by a skilled veterinarian is still essential.