Background and history

Pasteurella multocida bacteria are commonly involved in respiratory disease in pigs and they may be toxin-producing or non-toxin-producing strains. Either can cause pneumonia in their own right but the non toxin ones are common secondary opportunist invaders associated with primary EP or PRRS infections. Pasteurella multocida type A causes pneumonia.

Clinical signs

Acute disease

• Severe sudden pneumonia affecting all the lung tissue.
• High temperatures.
• Discharges from the nose.
• High mortality.
• Pigs show rapid breathing.
• Blue discoloured skin particularly on the extremities of the ears (caused by toxins or heart sac infections).

Sub-acute disease

The condition usually affects pigs between 10 and 18 weeks of age.

• Pneumonia which is less severe but often complicated by heart sac inflammation and pleurisy.
• Coughing.
• Discharges from the nose.
• Emaciation. Poor body condition / wasting.
• Increased mortality.

Diagnosis

This is carried out by post-mortem examination and isolation of the organism from the lungs.

Causes

Concurrent disease such as PRRS, Flu and EP predispose.

Prevention

• Carry out procedures as described under respiratory diseases and control strategies.
• Vaccines are available but are not very effective.
• EP vaccination often prevents the pasteurella invading the lungs.

Treatment

Infection with Pasteurella bacteria is usually secondary to a more specific disease antibiotic treatments should follow as for enzootic pneumonia.