The ability of inactivated whole Streptococcus equi cell vaccines to give rise to protective antibody levels was studied in rabbits by serological means. The immunogenicity of vaccines prepared with field isolates was tested in rabbits and mice. Antibody titers were measured by Passive Heam Agglutination (PHA) test. Seven strains of Streptococcus equi subsp. equi were isolated, one classified biochemically as typical and other six as S.equi subsp. zooepidemicus. Results of PHA suggested that prepared vaccine from typical field strain give protective antibody titer against typical field strain but not against atypical strain and atypical field vaccine give protective immunity against atypical strains but not against typical field strain and suggested that combined vaccine give immunity against typical and atypical strains.