Tilapia Lake Virus (TiLV) and other diseases cause mass mortality and welfare harm in tilapia aquaculture globally. Disease management is a critical welfare dimension.
Tilapia disease welfare is significant given the scale of global production. TiLV causes neurological symptoms and skin damage before death, representing individual suffering across potentially millions of fish during outbreaks. Bacterial disease outbreaks cause similar welfare harm through swim bladder dysfunction, ulcerations, and organ damage. The welfare-positive approach prioritises biosecurity and vaccination over post-infection treatment, as prevention eliminates suffering entirely rather than reducing its duration. Selective breeding for disease resistance offers the longest-term welfare dividend by reducing baseline disease susceptibility.