Mycobacterium avium subspecies paratuberculosis (MAP) is an obligate pathogenic bacterium in the genus Mycobacterium. It is often abbreviated M. paratuberculosis or M. avium ssp. paratuberculosis. It is the causative agent of Johne's disease, which affects ruminants such as cattle, and also perhaps the human disease Crohn's disease. The type strain is ATCC 19698 (equivalent to CIP 103963 or DSM 44133).