Porcine respiratory disease complex (PRDC), often involving Mycoplasma hyopneumoniae, is a leading cause of chronic welfare compromise in growing pigs — causing persistent coughing, reduced growth, and increased mortality.
Porcine respiratory disease complex causes insidious and prolonged welfare compromise that is easy to underestimate because affected pigs continue to eat and grow, albeit more slowly. The persistent coughing that characterises PRDC is not merely an inconvenience — it reflects chronic airway inflammation that disrupts normal breathing, disturbs sleep and rest behaviour, and causes the physical effort of recurring respiratory episodes. Secondary bacterial pneumonia creates acute welfare emergencies on top of the chronic baseline, causing fever, severe respiratory distress, and rapid deterioration. The extremely high prevalence of Mhyo infection across intensive pig populations means that this is a welfare issue affecting hundreds of millions of animals globally. Vaccination, biosecurity, and housing improvements can substantially reduce disease burden, and the economic case for these interventions — improved growth rates and reduced mortality — aligns with the welfare case.