Antibiotic use in aquaculture raises both fish welfare and public health concerns. Understanding how antibiotics affect fish health, when their use is appropriate, and how resistance develops helps identify welfare-positive alternatives.
Antibiotic use in aquaculture sits at the intersection of fish welfare, antimicrobial stewardship, and food safety. From a welfare perspective, antibiotics are an important treatment tool when bacterial disease causes fish suffering — withholding effective treatment to avoid antibiotic use would be a welfare failure. The welfare concern arises with prophylactic use (administering antibiotics to prevent disease rather than treat it), which drives resistance without direct welfare benefit to the treated fish. Norway's achievement of near-zero antibiotic use through vaccine development demonstrates that prophylactic antibiotic reliance is an industrial choice, not an inevitability. The public health dimension — antimicrobial resistance (AMR) — is itself a welfare concern at the human population level. Aquaculture welfare certification that limits antibiotic use while requiring effective disease management aligns fish welfare, AMR stewardship, and food safety goals.