Evaluation of conformation against traits associated with dressage ability in unridden Iberian horses at the trot

The work describes and compares the conformation traits and gait characteristics in the main native Iberian dressage Purebreds (Lusitano, Spanish and Menorca horses). In total, 4 strides belonging to each of 66 males (4-14 years old) were recorded at handled trot, using a 3D semi-automatic movement analysis system. Principal component analysis (PCA) and intraclass Correlations (iC) were computed. The Menorca Purebred showed proportionally higher limbs (23.8 and 15.1cm for the forelimb cannon and pastern lengths), the Lusitano Purebred had larger inclinations (66.1°, 37.7° and 47.9° for the scapula and pastern angles), and the Spanish Purebred presented a longer scapula (41.5 cm) and a larger hip angle (132.1°), apparently showing a better conformation for dressage gaits. However, the three breeds presented undesirable tarsus joint conformation (155.5°) for dressage performance. In general, all of them showed good features in the kinematics of the forelimbs. Nevertheless, the functional capacity of their hindlimbs and linear parameters probably need to be improved for their competitiveness.