Pathogenesis

PATHOGENESIS
  • A.lignieresii , is a commensal of oral cavity and the intestinal tract.
  • It can survive for upto five days in hay or straw.
  • The actual mechanisms of actinobacilli are unknown.

Actinobacillosis

  • Bovine actinobacillosis is spread by the lymphatics. The specific disease is wooden (timber) tongue, but granulomatous lesions can also involve the head, neck and limbs.
  • Less commonly, the lungs and other internal organs are also affected.
  • A.suis : Infection occurs via the aerosal route by close contact or through skin.
  • Once the organism has entered the blood stream it spreads rapidly throughout the body.
  • Several factors, LPS, cytotoxin etc are responsible for gross lesions and they are usually seen in the lungs, kidney, heart, spleen, intestines and skin.
  • The lungs may also be filled with serous or serofibrinous exudates with pleuropneumonia.
  • A.pleuropneumoniae : The organism enters the lungs, multiplies rapidly.
  • During growth the organism releases a large quantity of OMP, LPS, cytokines and other factors which causes destruction of neutrophils that is likely to be responsible for the massive and tissue damage.
  • Diseases caused by the pathogenic actinobacilli

Species
Host
Disease
A. lignieresii
Cattle
Bovine actinobacillosis (Wooden (timber) tongue )
Polygranulomatous lesions around head, neck and limb
A.equuli
Neonatal foals
Mares
Sleepy foal disease or Joint ill
Abortion./septicaemia
A.pleuropneumoniae (Haemophilus pleuropneumoniae)
Pigs
Arthritis, nephritis and endocardtitis
A.suis
Pigs under 3 months of age
Older pigs
Acute fatal septicaemia
Arthritis, pneumonia and pericarditis
A.seminis
Rams
Epididymitis

 
Last modified: Monday, 4 June 2012, 5:27 AM