Zoonotic diseases transmissible between pigs and humans create welfare challenges requiring biosecurity practices that protect both pig and human health.
The interface between pig and human health creates welfare considerations in both directions. Zoonotic diseases cause suffering in pigs as well as posing human health risks. Influenza in pigs causes respiratory disease with fever, cough, and systemic illness. Streptococcus suis causes meningitis and joint disease in affected pigs. Salmonella colonization, while often subclinical in pigs, reflects environmental conditions that may indicate broader welfare problems. The management practices that reduce zoonotic disease risk - good hygiene, appropriate stocking densities, reduced antibiotic pressure - generally align with improved pig welfare, creating synergies between animal welfare and public health goals.