Porcine respiratory disease complex Flashcards
What are most common bacterial porcine respiratory disease complexes?
*mycobacteria hyopneumoniae
*B. bronchiseptica
*P. multocida
*A. pleuropneumoniase
*H. parasuis
*S. suis
What are the most common viral porcine respiratory disease complexes?
*PRRSV
*SIV
*PRCV
*PRV
*PCV2
How can pigs be infected?
*Direct pig to pig contact
*Infected semen
*People - footwear, clothing, hands
What are management and enviromental factors to control disease transmission?
*Ventilation
*Overcrowding / stocking density
*mixing of pig age groups
*Biosecurity + Disinfection
What are the 3 immunity an animal gets?
*Innate immunity - from conception / in utero
*Passive immunity - MDA
*Adaptive immunity - Cell mediated immunity + humoral immune response
When should pregnant sows be vaccinated to PRRSV?
Only vaccinate in had previous exposure to virus as it is a live vaccine so can cause disease
What are the most common strains of swine influenza virus SIV in pigs?
*H1 N1
*H1 N2
*H3 N2
What is the incubation period of swine influenza virus?
12-48hrs
What are symptoms of SIV in piglets?
*It would be unusual to see any signs of swine flu in the sucking pig unless disease entered the herd for the first time.
*Colostrum may prevent infection during the sucking period.
*Coughing.
*Pneumonia.
*Fever
What are symptoms of SIV in sows?
*High temperatures which cause abortions.
*Widespread coughing.
*Pneumonia
When the virus first enters the herd two or three animals may be observed sick for the first two days, followed by:
*A rapid explosive outbreak of inappetence and clinically very ill pigs.
*The effects on the reproductive system follow the sudden onset of a rapid
spreading respiratory disease with coughing, pneumonia, fevers and inappetence.
*Acute respiratory distress persists over a period of 7-10 days (depending on the amount of contact between groups of sows).
What are causes / contributing factors of swine influenza virus?
*Infected animals including people, pigs and birds.
*Carrier pigs.
*Birds particularly water fowl, are reservoirs of infection.
*Secondary bacterial infections.
*Fluctuating temperatures.
*Stress.
*Wet bedding and floor surfaces.
*Poor nutrition
What does porcine circovirus type 2 affect?
Growing pigs
*Repro failure in breeding herds
*Shed in boar semen
What is Enzootic pneumonia also known as?
Mycoplasma hyopneumoniae
What does M. hyopneumoniae cause?
*Uncomplicated infection on its own + relatively unimportant with mild effects
*But with other infections - App, Hps, Pasteurella, PRRSV + SIV = pneumonia becomes more complex with serious effect on pig
How is Enzootic pneumonia diagnosed?
*Post mortem = lungs = atelectasis + lobar discoloration
*Histology of lesions
*Confirm with ELISA, PCR / Culture
What are factors that can increase mycoplasma hyopneumoniae disease likelyhood?
*Overcrowding and group sizes in any one environment of more than 200.
*Variable temperatures and poor insulation.
*Houses with poor hygiene and high levels of carbon dioxide and ammonia.
*High dust/bacteria levels in the air.
*Pig movement, stress and mixing.
*A shortage of trough space.
*Housing with a continuous throughput of pigs.
*Other concurrent diseases.
*Poor nutrition.
*Slatted floors and liquid waste
What does Bordetella bronchiseptica do?
*Colonizes ciliated epithelium of respiratory tract, resulting in decreased mucociliary apparatus function + pneumonia
*Necrohaemorrhagic pleuropneumonia lesions in young pigs
*Tan firm bronchopneumonia in older pigs
**CRANIOVENTRAL distribution
How is Bordetella bronchiseptica diagnosed?
*Isolation of organism from nasal swabs, trachea + lungs
Bordetella bronchiseptica on its own is clinically + economically of no consequence, when is it a problem?
*If toxigenic pasteurella present = 2 organisms = severe progressive rhinitis / PAR progressive atrophic rhinitis
