Atrophic Rhinitis

Rhinitis is inflammation of the tissues inside the nose where the nose may become distorted (atrophy).

Alternative names: Progressive Atrophic Rhinitis, PAR


Rhinitis as a general term means nostril’s tissue swelling, and can be caused by a wide variety of bacteria, virus and irritating substances. This condition rarely originates a clinical disease in adult pigs. Atrophy means upper respiratory tract tissue is damaged, shrink and deformed. The disease has two presentations:

  • Mild and non-progressive, in which the infection or irritation occurs during a period of 2 to 3 weeks. After that, the swelling stops and nasal turbinates cure, being normal again.
  • The most severe form of progressive atrophic rhinitis (PAR) in which strains of Pasteurella multocida type D and Bordetella bronchiseptica produce toxins that damage the nasal tissue. When both pathogens are present in the farm, they cause a continuous inflammation in lactating piglets and growing pigs, causing atrophy of tissues and deformities in the nose.



  • Not clinical signs.
  • Distortion of the nose.

Lactating piglets

  • Sneezes.
  • Tearing.
  • Nasal discharges that sometimes present blood.
  • Distortion of the nose.

 Weaners and growers

  • Blood stained sneezes.
  • Tearing.
  • The nose twists, shrinks and wrinkles.
  • Weight gain and daily growth decrease.
  • Feed conversion ratio increases.
  • Increase of respiratory diseases.

Causes / Contributing Factors

  • The disease is transmitted from one farm to another through carrier pigs, clothes, equipment, etc.
  • The transmission inside the farm is through aerosols between pigs, or through mouth-to-mouth contact.
  • Is more frequent in farms with a young breeding herd, especially those ones having high gilt numbers.
  • Multi-lactation systems (piglets suck from more than one sow) increase the disease spread.
  • Inadequate ventilation.
  • Environments with high amounts of dust or ammonia.
  • Toxic gases.
  • Deficient environment and nutrition increase the severity.


  • Clinical signs especially deviated snouts.
  • Nasal swab culture.
  • Evaluation of nasal turbinates and septum through slaughter checks and on-farm necropsies.



  • All adult animals must be vaccinated twice with a difference of 4 to 6 weeks between vaccinations. Modern vaccines are very efficient.
  • Then, sows must be vaccinated 4 to 6 weeks before farrowing.
  • Sometimes piglets must also be vaccinated at 1 and 4 weeks of age.
  • Early weaning of piglets <12 days of age to an off-site nursery.
  • During specific elimination programs, strategic use of antibiotics can be used.