VMC 311: Systematic Veterinary Bacteriology and Mycology (2+1)

INTRODUCTION

• Salmonella is a Gram negative, aerobic or facultatively anaerobic rod. It is motile by peritrichous flagella except S. gallinarum and S. pullorum. It does not ferment lactose.
• They are resistant to certain chemicals such as Brilliant green and sodium deoxycholate, which can be used in the media for their selective isolation.
• These organisms possess O, H and sometimes Vi antigens.
• These organisms now comprise more than 2200 different serotypes. Serotypes such as S.typhi, S.paratyphi A and S.paratyphi C are common to man.
• Similarly among animals there are some organisms which show a particular specificity for certain species eg:
  • S. dublin – cattle
  • S. abortus equi – horses
  • S. abortus ovis – sheep
  • S. cholerae suis – pigs
  • S. pullorum and S. gallinarium – poultry
  • S. typhimurium – animals and humans
• Salmonella causes
• Typhoid, paratyphoid in man
• Gastro enteritis in swine.
• Abortions in sheep, cattle and equine.
• Bacillary white diarrhoea and fowl typhoid in poultry.