Agathotychus (Ancient Greek: Ἀγαθότυχος) was an ancient veterinary surgeon, whose date and history are unknown,[1] but who probably lived in the 4th or 5th century AD.[2] Some fragments of his writings are to be found in the collection of works on this subject first published in a Latin translation by Joseph Ruellius, Veterinariae Medicinae Libri duo.[3]