Pasteurella

• Genera of Pasteurellaceae

  • Pasteurella
  • Mannheimia
  • Actinobacillus
  • Haemophilus
  • Lonepinella
• Pasteurella

  • Gram negative, small rods or coccobacilli
  • Bipolar staining, staining only the tips of the cell is demonstrable with: wright's stain giemsa stain leishman stain
  • Non-motile, non-spore-forming
  • Aerobic to microaerophilic or facultative anaerobic
  • Oxidase and catalase positive (most species, except Pasteurella caballi)
  • Reduce nitrate to nitrite
  • Attack Carbohydrates fermentatively
  • Grow best on media supplemented with serum or blood
• Sources/Reservoir of Pasteurella and Mannheimia

  • Commensals on the mucosae of the upper respiratory tract of animals
  • Short survival
• Virulence Factors of Pasteurella and Mannheimia

  • LPS is a potent endotoxin that can alter bovine leukocytes function and is directly toxic to bovine endothelial cells
  • Fimbriae that enhance colonization
  • Capsule is antiphagocytic - inhibits complement mediated destruction of the organism of serum (prevent membrane attack complex)
  • Leukotoxin is a pore forming cytolysin that affects leukocytes and platelet function when present at a low concentration and causes cytolysis at high concentrations
  • Dermonecrotoxin (Atrophic Rhinitis) that stimulate bone resorption in the area of the turbinates
• Diagnosis of Pasteurella

  1. Direct microscopy with distinctive bipolar staining (Wright, Giemsa, or Leishman stain)

  2. Growth characteristics and biochemical test

  3. Selective medium containing clindamycin (2kg/ml) or neomycin, bacitracin, actidion

  4. Serotyping by agglutination agar and gel diffusion

  5. Colony morphology
• Pasteurella multocida serogroups


  • A
  • B
  • D
  • E
  • F
• Pasteurella hemolytica biotypes


  • Biotype A (Mannheimia hemolytica) - ferments arabinose
  • Biotype T (M. trehalosi) - ferments trehalose
• Pasteurella multocida B:2 E:2


  Haemorrhagic Septicemia (Barbone)
• Pasteurella multocida B:2 E:2 - Haemorrhagic Septicemia


  • Host: Buffalo and cattle
  • Predisposing factors: Overwork, poor body conditions, monsoon rains
  • Transmission: Endogenous infections, aerosol
  • Incubation period: 2-4 days
  • History and Clinical signs: sudden onset of high fever, respiratory distress, cyanosis of the mucous membrane characteristic edema of the laryngeal region dysentery, recumbent and death, death without prior sighs of illness may occur 24 hrs post infection
  • Mortality rates: 50-100%
  • Lesions: petechial haemorrhage, enlarged LN, blood-tinged fluid in the pleural cavity and pericardial sac
  • Treatment and Prevention: Antibiotic therapy in the early febrile stage (Oxytetracycline), Vaccination (Bacterins and MLV)
• Mannheimia hemolytica & Mannheimia trehalosi - Septicemic Pastuerellosis


  • Host: Lamb (less than 3months old) - M. hemolytica, Sheep (5-12months) - M. trehalosi
  • Transmission: Endogenous infection (M. trehalosi) tonsillar tissues of carrier sheep aerosol
  • Clinical signs: sudden death, mortality rate may approach
• Mannheimia hemolytica A1, A6 - Ovine Pneumonic Pasteurellosis


  • Host: Sheep
  • Predisposing factors: Adverse climatic conditions or concurrent infection with respiratory viruses such as Parainfluenzavirus 3
  • Transmission: Endogenous infections, aerosol
  • Diagnosis: Clinical signs - sudden death in some, acute respiratory distress in others, Microscopy and bacterial cultures
  • Mortality rates: 1-10%
  • Morbidity: 50%
  • Lesions: ventral consolidation in the cranial lobes of the lungs fibrinous pleural and pericardial effisions
  • Treatment and Prevention: Antibiotic therapy in the early course of the disease - OTC TMPS Ampicillin, Vaccination, Management - reduce stress
• Pasteurella multocida Type D or A Atrophic rhinitis


  • Host: Young pigs (3-8 weeks of age)
  • Predisposing factors: Overstocked and poor ventilation
  • Coinfection: Bordetella bronchiseptica
  • Diagnosis: Clinical signs - excessive laceration, sneezing and occasionally epitaxis, snout becomes gradually shortened and wrinkled lateral deviation of the snout as the disease progresses, Microspy and bacterial cultures Elisa and PCR
  • Treatment and Prevention: Chemiprophylaxis w/ TMPS Tylosin or tetracyclines, Vaccination (bacterins, MLV), Improvement in husbandry practices
• Pasteurella multocida type A - Fowl cholera


  • Host: Domestic and wild birds
  • Transmission: Exogenous infection (contamination from environment) droplets, food or water contamination
  • Diagnosis: History and clinical presentation - Acute septicemia, depression, sleepiness, inappetence diarrhea, Microspy and bacterial cultures
  • Lesions: hemorrhages on serous surfaces and accumulation of fluid on body cavities, swollen wattles, sternly bursae, and joints due to accumulation of fibropurulent exudates
  • Treatment and Prevention: Antibiotics (TMPS, tetracyclines), Vaccination (bacterin)
• Pasteurella multocida type A - Snuffles


  • Host: Rabbits
  • Transmission: Exogenous infection (contamination from environment) droplets, food or water contamination
  • Predisposing factors: stress factors such as over crowding, chilling, transportation, concurrent infections & poor ventilation resulting in high levels of atmospheric ammonia
  • Transmission: Endogenous infection (commensals in the URT of healthy carrier rabbits)
  • Diagnosis: mucopurulent nasal discharge which cakes on the forelegs sneezing and coughing, sequelae include conjunctivitis
  • Treatment and Prevention: Antibiotics, Eliminate Predisposing factors
• Mannheimia hemolytica A1, A6 - Bovine Pneumonic Pasteurellosis/ Shipping Fever

  Host: Young cattle

  Predisposing factors: Severe stress as transportation, assembly in feedlots, and close confinement

  Coinfection: Pasteurella multocida, Parainfluenzavirus 3, Bovine Herpesvirus 1, Bovine Syncitial virus

  Transmission: Endogenous infections, aerosol
• Mannheimia hemolytica A1, A6 - Bovine Pneumonic Pasteurellosis/ Shipping Fever

  Clinical signs: sudden onset of fever, depression, anorexia, tachypnea, serous nasal discharge, marked cough and ocular discharge - mixed infection

  Mortality rates: 1-10%

  Morbidity: 50%

  Lesions: cranial lobes of lung areas red, swollen and consolidated there is often an increase overlying fibrinous pleurisy

  Treatment and Prevention: Antibiotic therapy in the early course of the disease - OTC TMPS Ampicillin, Vaccination, Management - reduce stress
• Pasteurella hemolytica Biotype A

  Gangrenous Mastitis (Blue Bag)

  Sheep
• Pasteurella canis

  Oral cavity

  Dog, Man
• Pasteurella dagmatis

  Oral cavity and Intestinal tract

  Dog, Cat, Man
• Pasteurella stomatis

  Respiratory tract

  Dogs, Cats
• Pasteurella caballi

  Respiratory Infection

  Horse
• Pasteurella aerogenes

  Intestinal tract

  Pig
• Pasteurella anatipestifer

  New Duck Disease

  Duck
• Pasteurella testudinis

  Turtles, Tortoise
• Pasteurella granulomatis

  Finrogranulomatous Disease

  Catttle (Brazil)
• Pasteurella pnuemotropica

  Respiratory tract

  Rodents