Respiratory Disease and Pig Welfare

Respiratory disease is the leading cause of productivity loss and suffering in pig production, driven by poor ventilation, high stocking density, and pathogen exposure.

Key Facts

PRRS, swine influenza, and Mycoplasma hyopneumoniae are the primary respiratory pathogens in pigs
Poor air quality with high ammonia, dust, and humidity dramatically increases respiratory disease risk
Pigs with subclinical respiratory disease have reduced growth rates and higher susceptibility to other conditions
Lung lesions at slaughter are a validated welfare indicator reflecting respiratory disease burden

Welfare Considerations

Pig respiratory welfare is fundamentally a housing quality issue: well-ventilated, appropriately stocked buildings with low ammonia and dust have dramatically lower respiratory disease rates. Pigs with respiratory disease experience chronic discomfort, reduced appetite, and secondary welfare impacts from immune suppression. Post-mortem lung lesion scoring at slaughterhouses provides a population-level welfare indicator that reflects the lifetime respiratory health of pigs from different farms. Farms with consistently high lung lesion scores are flagged for welfare investigation and support.

What You Can Do

Support welfare certification schemes that use slaughterhouse lung lesion data
Advocate for mandatory ventilation standards in pig housing
Choose pork from farms with documented low respiratory disease rates
Support research into cost-effective ventilation improvements for intensive pig buildings