Difference between revisions of "Pasteurella species and Mannheimia haemolytica"
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*Common commensal of the upper respiratory tract and gastrointestinal tract mucosa of animals | *Common commensal of the upper respiratory tract and gastrointestinal tract mucosa of animals | ||
− | *Usually opportunistic organisms, causing disease during times of stress, low resistance or concurrent | + | *Usually opportunistic organisms, causing disease during times of stress, low resistance or concurrent infection |
*Resist phagocytosis by their capsule | *Resist phagocytosis by their capsule | ||
*Not part of the human bacterial flora | *Not part of the human bacterial flora |
Revision as of 17:53, 16 December 2007
- Pasteurella multocida in Atrophic rhinitis of pigs and atrophic rhinitis
- Peritonitis in sheep
- Permeability types of pulmonary oedema.
- Can be secondary to IBR
- Causes 'Snuffles' in rabbits
- Manheimia haemolytica biotype A serotype 1 (90%) and Pasteurella multocida cause pneumonic pasteurellosis
- Pasteurellosis in pigs
- Can cause vascular fragility, leading to haemorrhagic disease.
- M. haemolytica and P. multocida may contribute to Enzootic pneumonia of calves
- Often follows parainfluenza - 3 infection of cattle
- P. haemolytica in enzootic pneumonia of lambs
- In pyothorax
- P. multocida in cellulitis in cats
Overview Pasteurella
- Common commensal of the upper respiratory tract and gastrointestinal tract mucosa of animals
- Usually opportunistic organisms, causing disease during times of stress, low resistance or concurrent infection
- Resist phagocytosis by their capsule
- Not part of the human bacterial flora
Pasteurella Properties
- Short Gram-negative bacilli or coccobacilli
- Oxidase-positive
- May show bipolar staining
- Catarrhal odour
- Produce endotoxins which cause host damage and death
Pasteurella multocida
- Large grey colonies on blood agar
- Not haemolytic
- Do not grow on MacConkey
- Four capsular serotypes, A,B,D,E and recently F
- Primary and secondary pathogen
- Responsible for secondary infections following primary viral and mycoplasmal infections, especially in the lungs, for example during pig enzootic pneumonia
- Typa A
- Commensal in upper respiratory tract of animals in UK
- Primary pathogen in fowl cholera - a septicaemia in chickens and turkeys
- Secondary pathogen commomly repsonsible for dog and cat bite wound infections in humans and animals
- Some strains involved in Atropic Rhinitis in pigs, and produce osteolytic toxin
- Involved in rabbit Snuffles (Pateurellosis)
- Type B
- Causes Haemorrhagic Septicaemia of cattle in Southern Europe and Asia
- Type D
- Primary and secondary pathogen
- Causes Atropic Rhinitis along with Bordetella bronchiseptica in pigs
- Produces an osteolytic toxin, which stimulates osteoclast, inducing bone resorption
- Type E
- Causes Afican Bovine Haemorrhagic Septicaemia
Pasteurella pneumotropica
- Carried in nasopharynx of many small rodents
- Causes pneumonia in rodents as a secondary disease
Mannheimia
Mannheimia haemolytica
- Cause of epizootic pneumonia in cattle, also known as Shipping Fever, Transit Fever or Bovine Pneumonic Pasteurellosis
- Usually secondary to viral infections such as PI3 or IBR, or to mycoplasma
- Causes pasteurellosis in sheep
- Beta-haemolytic on blood agar
- Grow weakly on MacConkey agar
- All are Manheimia A biotypes
- Strains often produce a cytotoxin, known as leukotoxin, which kills leukocytes of ruminants
- Leukotoxin is a member of the RTX group toxins, and is probably largely responsible for the pasthogenicity of the bacteria in septicaemia and pneumonia
Mannheimia glucosida
- Previously biotype A11
Mannheimia trehalosi
- T biotypes - trehalose fermenters