- Caused by Mycoplasma hyopneumoniae and Mycoplasma hyorhinis
- Also called mycoplasmal pneumonia
- Major cause of unthriftiness in young pigs
- Pneumonia in weaned pigs
- Cough, reduced growth rate
- Attached to cilia - no mucociliary clearance
- Usually non-fatal unless there is secondary infection (e.g. Pasteurella multocida)
- Gross pathology:
- Confluent consolidation of the cranioventral lung lobes
- In other areas there may be small red to grey focal lesions evident which indicate the bronchiolar orientation of the inflammatory process
- Histologically
- Changes result from a catarrhal bronchointerstitial pneumonia
- In chronic cases, prominent accumulations of lymphoid cells can be seen around airways and blood vessels