Test 2 -Pasteurella Flashcards Preview

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Flashcards in Test 2 -Pasteurella Deck (29):

Pasteurella multocida General

• Gram negative
• Obligate symbiotic
• Little resistant in environment

• Capsule: types A-E (antigenic properties)
--------- Type A: mucoid capsule + hyaluronic acid
---------- Subdivision of PM based on somatic antigens (1-16)


Pasteurella multocida Virulence factors

• Adhesins: fimbriae and outer membrane proteins

• Capsule:
------- Adherence

------- Anti-phagocytic

• Cell wall: LPS- gram negative
• Iron acquisition: siderophores and outer membrane proteins

• Toxins

• RTX (repeats in toxin
-------- Leukotoxin and lysis of erythrocytes (hemolysis)

--------- Impairspulmonarymacrophagefunction
----------Inflammatory reaction with tissue destruction

• Rho activating toxin (Pasteurella multocida toxin, dermonecrotic toxin)

• Other:
• Hyaluronidase

• Neuramidase


Pasteurella multocida

hosts for high and low virulent strains

• High virulent strains
• Obligate pathogenic: septicaemiae

• In bovines, birds and rabbits

• Low virulent strains
• Facultative pathogenic (nose, tonsils): rhinitis, pneumonia • In pig, bovines and rabbits


P. multocida in rabbits: rhinitis (snuffles)

• May evolve to:
• Pleuropneumonia

• Otitis( can see because the head is tilled
• Conjunctivitis
• Abscesses


P. multocida in bovines

• Low pathogenic serovars (See bacterial bronchopneumonia in bovines)

• High pathogenic serovars:

Hemorrhagic septicaemiae

• Serotypes
• B:2 mainly in South East Asia
• E:2 mainly in Africa
• Not really in Europe nor in the USA

Serotypes are just FYI

• High mortalities (50-100%)
Spread by asymptomatic carriers(tonsils)

• Direct contact • Ticks and flea’s

• Therapy: Antiboditics do not work

• Inactivated vaccine


P. multocida in pigs

Atrophic rhinitis: See Bordetella bronchiseptica

Lung pasteurellosis
-----------Multifactorial disease
-----------Mainly capsule type A and somatic type 3

• Aerosol transmission
• Carriers (nose)
• Suppurative bronchopneumonia and fibrinous pleuritis


P. multocida in poultry: fowl cholera

• Different Capsular types

• Susceptibility differences
• Duck>goose>turkey>chicken>pheasant>partridge> guinea fowl


P. multocida in poultry:

fowl cholera Pathogenesis

• In nose and beak of healthy animals

• Entrance: mucosae mouth, throat, trachea, skin lesions (eg. cat bites)

• Septicaemiae
--------- acute, subacute, chronic disease progression (depending on host)

• Excretion: nose, mouth

------Drinking water, feed!


P. multocida in poultry: fowl cholera Symptoms

• Chicken and turkey

------Mainly young adult

-------Chicken: chronic
-------------------- Sneezing, nose excretions, oedema head

• Acute: sudden dead
• Cat bites: always hyperacute in all bird species


P. multocida in cats and dogs

• Licking of wounds: wound infection

Biting wounds and scratch lesions
• Cats biting a bird: Bird gets Pasteurella septicaemiae!

-------------- In the eventual case: always give antibiotics (the bird will not survive the infection)

• Less virulent serotypes


---------- Tonsils


Humans and biting wounds by cats and dogs

• Pasteurella spp
• Neisseria spp
• Capnocytophaga spp

 Above are Frequently with obligate anaerobes involved Sometimes + Staphylococcus spp., Streptococcus spp.


• Bartonella henselae (cat)

Local symptoms, regional Lymph nodes


Bacteremia and tissue localization





• Prevention of Infection from Bites

• Prevent

• Wound disinfection

• When antibiotics:

• Fever

• hands/face
• Stab wound (deep and can get anaerobic)

• Pus
• Whensurgeryisnecessary
• Risk groups (lower immunity)


Mannheimia hemolytica

Mannheimia hemolytica used to be Pasteurella hemolytica


Mannheimia hemolytica


• Obligate symbiotic
• Capsule types (A-F)
• Low environmental resistance


Mannheimia hemolytica

Virulence factors

• Leukotoxin: RTX family (related to Apx toxins of APP,...)

------------ Low dose: oxidative metabolism in NF & MF
--------------High dose: lysis of phagocytes
--------------- Only effective on leucocytes of bovines and sheep!

---------------Strongly antigenic
• Transferrin binding proteins

• Endotoxins (LPS)
• Capsule (anti-Phagocytosis)

• Fimbriae


Mannheimia hemolytica

In different animals


Facultative pathogenic

----------------Bovine: tonsils/nasopharynx (low numbers)

----------------Sheep: nose and tonsils

Pneumonia (both primary and secondary infection are possible)



All serotypes

Frequently found in the nose

Little to no acquired antimicrobial resistance


Serotypes 1, 2, 6

Seldom found in nose

Quite some acquired antimicrobial resistance

Role in bacterial bronchopneumonia in calves


Bacterial broncho-pneumonia in calves

• Multifactorial disease

------------ Environmental factors- grouping cows together

-------------Viral infections
-------------Bacterial infections

• In young animals


Bacterial broncho-pneumonia in calves

Primary pathogens possibly involved:
• M. haemolytica
• Mycoplasma bovis
• Histophilus somni (+ CNS SY: sleeper disease)

• Ureaplasma diversum

• Mycoplasma dispar (chronic respiratory disease)

• Salmonella Dublin


- don't need to know for test 2, but will need to know for the final


Bacterial broncho-pneumonia in calves

• Secondary pathogens possibly involved

Pasteurella multocida (low, medium virulent strains)

-------------- Facultative pathogen
---------------Respiratory system

• Trueperella pyogenes

• Moraxella spp.


Shipping fever

Bacterial broncho-pneumonia in calves by M. haemolytica and P. multocida


when you have these two together----- you call them shipping fever



M. haemolytica and P. multocida

Pathogenesis: endogenic

• Stress (transport, environmental changes, viral infection,...)

• Multiplication at the nasopharynx of M. haemolytica


---------- Lung (aspiration of upper airway droplets)

------------------- Fibronecrotic bronchopneumonia

---------- Septicaemic phase (not so frequent)

• P. multocida: secondary pathogen

----------Capsule type A, (D)



M. haemolytica and P.


Pathogenesis: exogenic

Pathogenesis: exogenic

• Excretion of high numbers of MH by infected calves

• Other animals get colonized/infected


Immunity from shipping fever

• Mainly antibody mediated immunity

• Presence in tonsils: antibody production and partial protection

• Protective antigens:

----------Leukotoxin (not fully protective)

---------- Surface antigens

----------Transferrin binding proteins
• Vaccine: needs a combination of factors


Symptoms of shipping fever

• General symptoms

• Respiratory distress

- Generally doesnt' feel well


Lesions from shipping fever

• Different grades and depending on complicating infections

---------- Fibrinous necrotizing bronchopneumonia
----------Serofibrinous pleuritis
----------Well defined pneumonia zones


shipping fever



• Mannheimia haemolytica and

p. multocida

Mannheimia haemolytica

• Bacterial culture from

---------- Lungs

----------Nose (though difficult interpretation)

• Little resistant: quick to lab
• Pasteurella multocida:
• Culture from lung, BAL (nose)


Treatment of M. Hemmolytica and P. multocida

• Prevention!


---------- Feed: stomach fermentation

--------------------Lower energy concentration
• Vaccination (success is variable)

---------- Bacterins:+/-

----------Bacteria grown in Fe deprived media (transferrin binding proteins)+

----------Bacteria + leukotoxins +

• Antibiotics (evt. + cortico steroids)


Bibersteinia trehalosi


Septicaemiae at the age of 5-12 months; resembles bovine hemorrhagic septicaemia

DD -Clostridium perfringens enterotoxemia

Acute mortality

---------- Stress

----------Changes in feed


used to be a pasterella