Early mortality syndrome affects farmed shrimp in Asia, causing catastrophic losses and severe welfare impacts. Understanding and preventing it protects the welfare of billions of farmed crustaceans.
Early mortality syndrome causes acute welfare harm as affected shrimp experience hepatopancreatic destruction that impairs digestion and causes rapid death. While uncertainty about shrimp sentience remains, the scale of EMS impact — billions of animals dying from organ failure — warrants welfare attention on precautionary grounds. The economic devastation of EMS outbreaks has motivated significant industry investment in prevention, creating a welfare-economic alignment unusual in aquaculture. Farms with strong biosecurity, quality post-larvae sourcing, and good water management prevent EMS while also protecting the welfare of surviving animals through better overall conditions. The prevention infrastructure developed for EMS has improved general shrimp farm hygiene and welfare across the industry.