Antibiotics in Salmon Farming: What Is Antibiotic Stewardship and How Is It Managed?
(updated from May 14, 2026)
Antibiotic stewardship is a foundational pillar of raising healthy fish responsibly.
Like humans, all animals including fish, can become unwell at points throughout their lifetime. For some of these illnesses, the most effective treatment is antibiotics. While there are many types of antibiotics, they all target specific bacterial infections to bring animals back to health. When antibiotics are needed in salmon farming, their use is strictly controlled and does not result in residue in the final product, helping ensure salmon is safe to eat.
What is Antibiotic Stewardship?
Antibiotic stewardship is the responsible, limited, and carefully monitored use of antibiotics to maintain their long-term effectiveness while protecting animal health, welfare, and public health.
Responsible farming practices focus on animal welfare - preventing disease and mitigating illness quickly when it does occur. Antibiotics should never be used as a preventive measure and should only be used when absolutely necessary as stipulated by national regulation and veterinary professionals. This includes following codes of conduct for permitted classes of antibiotics to reduce the risk of antimicrobial resistance (AMR). AMR occurs when bacteria evolve to survive – making infections progressively harder to treat in both humans and animals. It is recognized by the World Health Organization as a global concern requiring national action plans.
Why Are Antibiotics Sometimes Used in Salmon Farming?
Salmon, like all animals, can develop bacterial infections - and when vaccines or preventative treatments are unavailable or insufficient, carefully managed antibiotic treatment may be required to restore fish health.
Salmon are raised in open water environments that are closely connected to surrounding ecosystems. This means changes in water temperature, salinity, and broader ocean conditions can influence fish health and pathogen exposure. This makes disease prevention more complex and context-dependent in aquaculture systems, and more difficult to fully control compared to land-based animals.
As a result, antibiotic use varies depending on local environmental conditions, disease pressures, and the availability of effective vaccines.
In Chile specifically, Piscirickettsiosis or Salmonid Rickettsial Septicemia (SRS) is a is a bacterial disease that impacts the farmed salmon population. There isn’t a vaccine to prevent this disease, making antibiotic stewardship essential if the disease does occur to ensure the continued efficacy of these treatments.
How is Antibiotic Use in Salmon Farming Managed?
Antibiotic use in salmon farming is managed through national regulatory frameworks, third-party certification standards, and veterinary oversight - all centered on three goals: restricting unnecessary use, preventing AMR, and ensuring food safety. While specific guidelines vary by country, these core principles apply globally:
1. Restricting unnecessary use
- A key component of antibiotic stewardship
2. Preventing AMR
- AMR is a global public health challenge linked to the misuse or overuse of antibiotics in both human and animal health. Responsible use is an important part of addressing AMR. In salmon farming, this means focusing on reducing reliance on antibiotics while ensuring animal welfare is not compromised.
- To put this in context: On average, GSI members use significantly lower levels of antibiotics than many other animal protein sectors, including chicken and beef production. This distinction matters, as it reflects decades of investment in vaccine development, fish health management, and regulatory compliance that has progressively reduced the industry's reliance on antibiotic treatment.
3. Ensuring food safety
- Countries have specific regulatory frameworks and authorities that oversee and assure food safety, including for farmed salmon. These authorities ensure that if antibiotics are needed, there is no antibiotic residue present in the salmon that people eat.
- A key mechanism that supports this is the mandatory withdrawal period. After any antibiotic treatment, a veterinarian prescribes a minimum waiting period before the fish can be harvested. This ensures that any traces of the antibiotic have cleared the fish's system entirely before it enters the food supply.
Even as the sector works to minimize antibiotic use, treatments are applied within strict global guidelines and at lower levels than in many other animal protein sectors.
As regulatory frameworks for antibiotic use in aquaculture continue to develop, international organizations point to the need for greater consistency, oversight and monitoring to support globally responsible practices. Global certifications and third-party standards play an important role in defining and verifying responsible practices across regions.
The ASC Farm Standard Certification outlines criteria for responsible antibiotic use, including:
- Use only under veterinary prescription and supervision
- Use only to treat diagnosed disease
- No use for growth promotion or routine preventative purposes
- Antibiotic sensitivity testing to inform treatment decisions
- Ongoing evaluation of treatment effectiveness
More broadly, international guidance from organizations such as the FAO, WHO, and the World Organization for Animal Health (WOAH) emphasizes a coordinated, systems-based approach. Key principles include:
- Prudent and responsible use of veterinary medicines
- Monitoring and transparent reporting of antibiotic use over time
- Ongoing surveillance of AMR
- Collaboration across industry, government, and science to reduce reliance while supporting animal health
What Is the Industry Doing to Reduce Antibiotic Use in Salmon Farming?
Efforts across the sector from industry stakeholders and beyond are key to translating global guidance and third-party standards into action. Through collaboration and innovation, these efforts help identify approaches to mitigate diseases, and support fish health, while reducing antibiotic use over time.
GSI and Member Efforts
GSI members have reduced average use of antibiotics by 72% since 2013, and 26% since 2020.
GSI Sustainability Report: Transparent reporting is essential in reducing the use of antibiotics in farmed salmon. GSI’s annual Sustainability Report has tracked members’ antibiotic use for more than a decade, providing a consistent baseline to measure progress. The report highlights the impact of fish welfare advancements while also helping members pinpoint opportunities for improvement and focus efforts where they can drive the greatest change.
A group of GSI members pose for a group photo at the ATC Patagonia research facility.
Broader Industry Efforts
Across the global salmon sector, collaborative initiatives are reinforcing the shift toward reduced antibiotic use by improving transparency, advancing prevention strategies and strengthening fish health management.
- Antibiotic Reduction:
- In Chile, the Chilean Salmon Antibiotic Reduction Program (CSARP) was established through a partnership between Monterey Bay Aquarium and the salmon farming industry to track collective performance and increase transparency. Its CSARP+ designation recognizes companies with strong health management plans and effective strategies to reduce antibiotic use.
- The Pincoy Project is a collaborative initiative, helping to build best practices for the Chilean salmon industry. The project is working to create collaborative strategies to improve fish farming, monitoring and reporting, all with the goal of reducing antibiotic use.
- Alternative Strategies: Public-private collaborations are also working to identify new vaccine and treatment options that help prevent disease, helping to lower the need for antibiotic intervention. The Yelcho Alliance, for example, launched its first experimental trial in 2025 to evaluate newly proposed vaccines for preventing SRS in Chilean salmon.
- Environmental Monitoring: Advancements in technology are also playing an important role. Today, approximately one in three salmon pens use advanced monitoring tools including AI systems to track fish health and environmental conditions in real time, helping farmers strengthen fish immunity and prevent disease.
"SRS drives up to 95% of antibiotic use in Chile and remains the sector’s most significant health challenge. Aquabench coordinates the Yelcho Alliance which unities public and private sectors to collaboratively advance development and availability of new immunological solutions for salmon farming, primarily vaccines against SRS to help reduce antibiotic use throughout the production cycle.”Daniel Woywood, general coordinator for Yelcho, Technical Manager at Aquabench.
What is the Future of Antibiotic Stewardship in Salmon Farming?
Continued awareness of antibiotic use and innovation toward improved fish welfare are essential in our efforts to further reduce antibiotic use in salmon farming. As we work to reduce antibiotic use, farmers ensure any treatments used are within global guidelines and do not leave residue in the fish we eat. As we look ahead, collaboration continues to be a central pillar as we work together to advance antibiotic stewardship. For an overview of GSI fish health and welfare priorities, see our Fish Health and Welfare page.