Pig Respiratory Disease: PRRS and Welfare Management

Porcine Reproductive and Respiratory Syndrome (PRRS) is the most economically significant disease in pig production globally and causes significant animal welfare harm.

Key Facts

PRRS virus causes respiratory disease, reproductive failure, and immune suppression in affected pigs
PRRS costs the US pig industry an estimated $664 million annually and affects virtually all production countries
Infected pigs show coughing, labored breathing, fever, and reduced growth rates indicating significant welfare impact
PRRS is primarily spread by direct pig-to-pig contact, aerosol transmission, and pig movement between sites
No fully protective vaccine exists - current vaccines reduce clinical signs but do not prevent infection
PRRS elimination programs using strict biosecurity, whole-herd vaccination, and population replacement have been successful in some regions

Welfare Considerations

PRRS causes significant welfare harm through respiratory distress, fever, and the immune suppression that allows secondary infections to cause additional disease. Pigs in PRRS-positive herds during active outbreaks show visible signs of illness - labored breathing, reduced activity, reluctance to eat - that indicate substantial suffering. The chronic PRRS-positive state causes ongoing subclinical welfare harm through reduced immune competence throughout production. The welfare case for PRRS control through biosecurity investment and elimination programs is strong: eliminating or controlling PRRS improves pig health and welfare throughout the entire production cycle, not just during acute outbreaks.

What You Can Do

Implement strict biosecurity protocols to prevent PRRS introduction including controlled animal movement and visitor protocols
Develop outbreak response protocols that prioritize sick pig welfare through appropriate treatment and pain management
Work with a swine veterinarian on population immunity management strategies appropriate to your herd status
Monitor for PRRS seroconversion through regular testing in herds maintaining negative status
Consider PRRS elimination programs if herd PRRS status is causing ongoing welfare harm and economic loss
Advocate for regional PRRS control programs that reduce transmission between farms in endemic regions