Porcine Reproductive and Respiratory Syndrome virus is among the most economically damaging and welfare-significant diseases in commercial pig production worldwide.
PRRS inflicts substantial suffering across all life stages of affected pigs. Sows experiencing reproductive failure lose multiple litters and endure the physiological stress of late-term pregnancy loss. Affected piglets struggle to breathe, fail to nurse effectively, and often die slowly over days. The immunosuppression caused by PRRS leaves survivors vulnerable to secondary respiratory infections that compound suffering. Farm-wide outbreaks can affect thousands of animals simultaneously. Management responses — including increased culling, high medication use, and destocking — create additional stress. Welfare standards that reduce crowding, improve air quality, and enable sick animals to be identified and treated promptly are especially critical in PRRS-endemic operations.