Medicated feed is the primary treatment route for many salmon diseases, but its use raises welfare and antimicrobial stewardship concerns that require careful management.
In-feed medication welfare involves the direct welfare of treated fish - ensuring sick fish actually consume therapeutic doses - and the welfare of wild species potentially affected by medication discharge. Fish that are too ill to eat cannot benefit from orally administered medication, making alternative treatment routes or earlier intervention important. The Norwegian experience demonstrates that antibiotic dependence in salmon farming is not inevitable - vaccination programs and improved husbandry can achieve dramatic reductions. Welfare-focused aquaculture reduces medication reliance by preventing the conditions that require treatment, benefiting fish welfare, ecosystem welfare, and antimicrobial stewardship simultaneously.