Milk – Borne Pathogens and Pasteurization Practice Test

Strain RB51 is a live attenuated vaccine used to protect cattle against brucellosis caused by Brucella abortus. It is specifically developed for this Brucella infection, helping prevent abortions and disease in livestock. The other diseases listed—Salmonellosis, Listeriosis, and E. coli mastitis—are caused by different organisms and have separate vaccines, so RB51 isn’t used for them. An added practical note: RB51 is a rough Brucella strain that aids in differentiating vaccinated animals from naturally infected ones on certain tests, which helps in disease surveillance.