The effect of the size and shape of chestnuts on the identification of horses

Abstract

A study was carried out on 11 horse breeds comprising of the Akhal Teke (n = 23); English Thoroughbred (n = 23); Arabian Thoroughbred (n = 18); Czech Warm-Blood (n = 21); Old Kladrubian horse (n = 20); Hucul horse (n = 20); Czech – Moravian Belgian horse (n = 20); Noriker horse (n = 7); Silesian Noriker (n = 14); Haflinger (n = 20); Shetland pony (n = 20) to determine the shape and size of chestnuts. Chestnuts of 206 horses classified in three phylogeny classes were measured and drawn. The necessary data (breed; sex; name; sire; dam; sire of dam; age of horse; colour of horse; colour of the chestnut; bone) were entered into a special form. In the form the outlines of the shapes of the chestnuts were drawn; using a calliper we measured the protrusion of the chestnut at its highest point and the width at the widest part of the chestnut. We found no identical or similar shapes of the chestnuts within the breed or phylogeny class. We confirmed that the outlines of the chestnuts can be used as identifying marks because they are unique for each horse. We also tried to determine how the size of the chestnut is related to the strength of the skeleton but we failed to prove this dependence statistically. Using the general linear model (GLM) we discovered a statistically highly significant effect of the phylogeny class on the height and width of the chestnuts on all four limbs. The age factor has a statistically highly significant effect on the width of the chestnut on both front legs. Sex has a statistically significant effect on the height of the chestnut on both hind legs.