The Collection of Pathological Anatomy and Veterinary Teratology is due to the work of Giovanni Battista Ercolani who in 1863, when it was decided to dismember the Laboratory of Comparative Anatomy founded by Azzoguidi (1807-1814), collected the 1,704 preparations concerning Pathological Anatomy and Veterinary Teratology to constitute the main nucleus of the Collection, expanded over the years. The collection consists of dry preparations, materials preserved in alcohol and teratological skeletons, together with color drawings and admirable models in plaster and wax; the historical-artistic importance of the preparations, in particular the unique colored plastics of their kind in the world, is accompanied by a didactic value, still useful today for all students of the Veterinary Faculty.