The aim of the study is to reveal the connections and inspirations between Roman and contemporary regulations of warranty, as an element of European heritage. The material for the study consists of Justinian’s “Digest”, Gellius’and Cato’s works, contemporary Polish warranty legislation –the Civil Code, its amendments and executive acts. Juridical, medical and philosophical views of ancient Roman lawyers on animal health in the mentioned material were examined and analyzed. The views of the ancient Romans reflected in Polish civil law were pointed out. Studies have been carried out, comparing the ideas that provide the background for legal norms of warranty. It has been proved how different defining of health and disease in veterinary medicine can affect divergent legal regulations in relation to animals sold. The functionality criterion was affirmed to be applicable not only as one of warranty premises, but also as a motor for legal development.