VMC 221: Veterinary Immunology and Serology (1+1)

COMPARATIVE TEST

• Injection of both avian and bovine tuberculin at side of neck at separate sites.
• Examined after 72 hours.
• If avian tuberculin site shows the greatest reaction, animal is considered to be infected with M. avium or M. paratuberculosis.
• If M. bovis site is showing more reaction, animal infected with M. tuberculosis or M. bovis.
• This test done when avian tuberculosis or Johne ’s disease is prevalent.
• PPD from M. bovis more specific in cattle as it gives less cross reaction with M. avium.
• Advantage: More specific than SID.
• Disadvantage: more complex