| development, testing and commercialization of a new brucellosis vaccine for cattle. | vaccines used against brucellosis do not generally protect completely against infection or abortion. genetic analysis has revealed differences in arrangements of dna sequences between these vaccine strains and the virulent parent strain and permits the specific identification of field isolates of b. abortus as wild-type or vaccine strain. b. abortus strain 19 is a low-virulence, live vaccine developed for use in cattle. although it is effective, strain 19 vaccine had a tropism for the placenta a ... | 2000 | 11193615 |