Difference between revisions of "Category:Bordetella species"

From WikiVet English
Jump to navigation Jump to search
Line 1: Line 1:
 +
{{frontpage
 +
|pagetitle =Bordetella species
 +
|pagebody =
 +
|contenttitle =Content
 +
|contentbody =<big><b>
 +
<categorytree mode=pages>Bordetella species</categorytree>
 +
</b></big>
 +
|logo =
 +
}}
 +
 
===Overview===
 
===Overview===
  
Line 52: Line 62:
  
  
<big>'''''<ncl style=bullet maxdepth=2 headings=bullet headstart=2 showcats=1 showarts=1>Category:{{PAGENAME}}</ncl></big>
+
 
  
  
 
[[Category:Bacteria]][[Category:Gram_negative_bacteria]]
 
[[Category:Bacteria]][[Category:Gram_negative_bacteria]]
 
[[Category:Rods]]
 
[[Category:Rods]]

Revision as of 12:25, 24 May 2010


Overview

  • B. bronchiseptica infects a wide range of animal species worldwide
  • B. avium resticted to birds
  • Normal inhabitants of upper respiratory tract
  • Cause repsiratory diseases including rhinitis, tracheitis, bronchitis and bronchiolitis
  • Exogenous or endogenous infection
  • Poor survival in the environment
  • Transmission between animals
  • Young animals particularly susceptible
  • Predisposing factors include stress and concurrent infections
  • High morbidity; low mortality


Characteristics

  • Gram negative rods
  • Strict aerobes
  • Grow slowly
  • Catalase and oxidase positive
  • Non-lactose fermentors
  • Grow on MacConkey agar
  • Toxigenic strains agglutinate mammalian red blood cells
  • Identical S form LPS in all strains of B. bronchiseptica - 1 diagnostic antigen
  • B. bronchiseptica haemolytic, whereas B. avium not
  • Affinity for ciliated respiratory epithelium


Pathogenesis and pathogenicity

  • Use pathogenicity factors such as filamentous haemagglutanin (only B. bronchiseptica), fimbriae and pertactin to adhere to ciliated respiratory epithelium
  • Produce toxins:
    • Adenylate cyclase (leucocyte toxin - kills phagocytes) (only B. bronchiseptica)
    • Tracheal cytotoxin (inhibits DNA synthesis in ciliated cells)
    • Dermonecrotic toxin
  • Pathogenicity factors activated by environment and genetic changes
  • Regulatory locus, BvgAS, mediates the activation
  • Phase variation: genetic switch of Bvg locus allows transciption of pathogenicity factors
  • Phenotypic modulation: temperature, magnesium ions and nicotinic acid affect expression of pathogenicity factors
  • Bvg positive allows expression of pathogenicity factors and toxins and colonisation
  • Bvg negative may allow survival in the environment with production of flagellae
  • Mucosal IgA prevent attachment of bacteria to cilia, but clearance from the respiratory tract may take weeks
  • Carrier animals are a source of infection


Diagnosis

  • Samples include nasal swabs, tracheal aspirates and exudates
  • Cultured on blood agar and MacConkey agar
  • Biochemical profiles
  • Slide agglutination tests for virulence of isolates

Pages in category "Bordetella species"

The following 3 pages are in this category, out of 3 total.