Pig respiratory system Flashcards
What is the typical agent that causes acute fibrinous necrotising pleuro-pneumonia
Actinobacillus pleuropneumoniae
What is the typical agent that causes chronic necrotising pleuro-pneumonia
Actinobacillus pleuropneumoniae
Typical agents causing embolic pneumonia (pyaemia)
Trueperella pyogenes
Staph aureus
What is the typical agent of disseminated broncho-interstitial viral pneumonia
Influenza
Typical agents causing viral interstitial pneumonia
PCV2
PRRSV
What is the causative agent of progressive atrophic rhinitis
Bordetella bronchiseptica
Toxigenic pasteurella multocida
What is the cause of catarrhal rhinitis
Influenza
What are the issues with selecting for good immune response genetics in pigs
Associated with poor growth and production
How does PRRSV have an immune-dysregulatory effect
Targets lung macrophages and kills them; this impacts both innate immunity and antigen presentation
How does PCV2 have an immune-dysregulatory effect
Reduced macrophage and lymphocyte numbers
How does mycoplasma hyopneumonia have an immune-dysregulatory effect
Stops cilia beating so lose muco-ciliary escalator
What does porcine resp coronavirus cause
A mild cough
NB: this is a mutant from the much mores serious enteric form and gives cross protection
What bacteria are primary agents in pneumonia
Actinobacillus pleuropneumoniae
B bronchiseptica
Which mycoplasma is a primary agent in pneumonia
M hyopneumoniae
What kind of pathogen is P multocida
= opportunistic pathogen; usually a commensal
Follows primary infection with influenza/mycoplasma/PRRSC
Signs and pathological lesions in pneumonic pasteurellosis
Small number of pigs (with secondary pathogen) showing coughing, inappetance, fever, low weight gain
Can get septicaemia and die if untreated
–> = some sick pigs against background of less severe disease (with primary pathogen)
Pathologically: consolidated patches of dependent lung lobes, mucopurulent exudate in airways
Some get interstitial nephritis due to immune complex deposition in chronic cases
Aetiology of actinobacillus pleuropneumoniae
Primary pathogen that adheres to tonsils and alveolar epithelium via pili and then can move down to lungs or pass to piglets
Produces haemolysins and cytotoxins and causes destruction of macrophages
Long term tonsil carriage in subclinical infection
Signs and lesions in actinobacillus pleuropneumoniae
Rapid onset fever, severe dyspnoea, coughing, sneezing, vomiting etc
Seen in piglets post-weaning; spread from those with mAb to susceptible pigs
Lesions = haemorrhagic with fibrinous pleurisy and necrotic centres in caudal or diaphargmatic lobes
How does serology for actinobacillus pleuropneumoniae work
Detects antibody against the apxIV toxin; but doesnt tell us anything about virulence of the strain