Genetic, historical and breeding aspects of the occurrence of the tobiano pattern and white markings in the Polish population of Hucul horses - a review

In recent years, different patterns of piebald/skewbald coat colour have become popular in horses. The tobiano pattern may appear in one of three forms: minimal, classic or maximal. The minimal variant can occur only as white spots on legs (crypto-tobiano), which may result in misclassification of the horse as solid-coloured with white markings. In Hucul horses it is particularly important to accurately determine the real coat colour because the breed standard specifies that white markings disqualify the animal from breeding. In Hucul horses, the tobiano pattern often shows as crypto-tobiano and is wrongly classified as white markings in official documentation of horses. The most reliable way for correct classification of coat colour is to analyse DNA for the presence of inversion in chromosome 3 (ECA3), which conclusively confirms or rules out the presence of the tobiano gene in the problematic horses.