Bernhard Lauritz Frederik Bang (June 7, 1848 – June 22, 1932), was a Danish veterinarian. He discovered Brucella abortus in 1897, which came to be known as Bang's bacillus. Bang's bacillus was the cause of the contagious Bang's disease (now known as Brucellosis) which can cause pregnant cattle to abort, and causes undulant fever in humans.Bang was awarded his M.D. in 1880 and began teaching at the Royal Veterinary and Agricultural University of Denmark in Copenhagen.