New trout standards Q&A

The standards come into effect on Wednesday, 23 July 2025.

The main changes being introduced in the 2025 RSPCA trout welfare standards are as follows (please note this is not an exhaustive list of the new standards, simply a guide to some of the bigger changes):

• Welfare outcome assessments: Regular welfare outcome assessments must now be conducted in fresh and seawater farms by a suitably trained member of staff.
  
  
• CCTV must be installed for the whole slaughter process: CCTV systems must cover the whole slaughter process, including initial system entry and exit, stunning, killing, and as fish pass through or into the post-stun assessment area.
  
  
• An updated list of prohibited slaughter methods: The new standards prohibit specific slaughter methods, such as asphyxiation and carbon dioxide narcosis, which the RSPCA doesn’t consider to be humane. The RSPCA standards only allow the use of humane percussion methods of slaughter (blunt force trauma), or electrical methods where fish are stunned, followed by bleeding or stun/kill methods using electricity.
  
  
• New standards for the use of non-medicinal treatments: A number of new standards have been introduced relating to the use of non-medicinal treatments for sea lice and gill disease. They will only apply to farmers rearing seawater rainbow trout (as of January 2025, there is just one member doing this).
  
  
• Improved checks for moribund fish with prompt humane culling where required: A new standard that specifically focuses on moribund (sick or dying) fish requires daily checks for moribund fish in all tanks and enclosures, with prompt, appropriate action (e.g. removal and humane culling) taken where required.
  
  
• An increased focus on reducing the need for antibiotic use: The RSPCA recognises the industry’s previous and ongoing work to encourage responsible use of antibiotics. A number of new standards have been included relating to responsible antibiotic use. The use of antibiotics must be reviewed annually or at the end of a production cycle. In light of the findings of the antibiotic use review, a written action plan aimed at reducing the use of antibiotics through improvements in animal husbandry must be developed and implemented.

• We recognise some of the new standards will require members to make adjustments, so it’s really important we provide enough time to make the necessary changes, and that we support and advise them during this process.
  
  
• New, potential or existing RSPCA Assured members who are in need of support or advice on how they can meet the new trout standards are encouraged to contact the RSPCA Assured’s farming and technical engagement team, who are very happy to help.

• We appreciate that this might be an additional task, but it’s a vital and worthwhile one.
• The antibiotic review plan is designed to fit within the VHWP, but as its own dedicated section, given its importance. This is to ensure it is explicitly reviewed at the end of each production cycle or on an annual basis.
  
  
• It’s widely accepted that antibiotics must be used responsibly across all farming sectors, and the new antibiotic review plans are a way of ensuring this is done.
  
  
• For example, keeping records and carrying out regular reviews can highlight where husbandry practices, or other preventative measures such as increased biosecurity or vaccination, can improve the health and welfare of fish, reducing or even removing the need for antibiotics.
  
  
• We hope the reviews will be beneficial to trout farmers and they’ll find spending the additional time on them worthwhile.

• We suggest looking at camera options such as GoPro, which can be moved to different locations as required.
  
  
• If an RSPCA Assured member has difficulty meeting this standard, we encourage them to contact RSPCA Assured’s farming and technical engagement team, and we will offer tailored advice and support.

• The process of measuring and recording the welfare of the fish, known as welfare outcome assessments (WOAs), is extremely important as it helps ensure the resources we provide and management practices implemented are effective in improving fish welfare.
  
  
• WOAs might include checking and recording the condition of fins, skin and eyes.
  
  
• WOAs are already requirements of the RSPCA welfare standards for other commonly farmed animals - including laying hens, chickens, pigs and dairy cattle. We recognise that WOAs for fish will require them to be handled (terrestrial animals can be visually assessed from a distance). But it’s worth this extra step as the data collected will be used to provide benchmarking for producers so they can see how they compare with others, and will help inform future versions of the welfare standards.
  
  
• We acknowledge that the requirement for WOA checks might look like yet another task for already-stretched farm staff to complete. For this reason we hope that most, if not all, the checks required as part of the new WOAs can be done at the same time as other processes and handling events (in fact this is encouraged to minimise the number of times fish are handled), so, in reality, it will only represent a small increase in workload. For example, some checks can be done at the same time as fish are being graded or vaccinated, and fish may already be sedated in order to keep stress to a minimum.
  
  
• We also anticipate that the information gathered from the WOAs will help staff identify and respond to any problems more quickly, improving the health and welfare of fish via the veterinary health and welfare plan and reducing the risk of mortality. This could potentially save both time and money later on.
  
  
• The standards relating to WOAs will be developed and refined in future, so we welcome feedback from RSPCA Assured members on their experience of implementing them and how they can provide even more benefits to both farmers and fish welfare.
  
  
• If an RSPCA Assured member has difficulty meeting this standard, we encourage them to contact RSPCA Assured, and we will provide tailored advice and support.
  
  
• The welfare outcome assessment standards in this edition of the standards focus on the time the fish are being grown on trout farms.
  
  
• In future, we may also develop WOA to be recorded at the time of slaughter. These may be included in the next version of the standards, following further research and consultation.

• We understand that non-medicinal treatments are sometimes repeated in close succession if, for example, a fish has sea lice after one treatment. 
  
  
• However, a scientific study has shown that when thermal treatments are repeated within a short period of time, the number and significance of injuries to fish increase.
  
  
• Repeated handling in a short timeframe is also known to cause excess chronic stress that can negatively impact fish welfare.
  
  
• By requiring explicit veterinary approval, the standards help ensure non-medicinal treatments are only carried out when absolutely necessary and will benefit the fish.
  
  
• The standards relating to non-medicinal treatments for sea lice and amoebic gill disease will only apply to farmers rearing seawater rainbow trout, and currently just one RSPCA Assured trout member. This company was given the opportunity to provide feedback when the standards were being developed

• If CCTV footage is unclear simply because of poor weather conditions at the time, this will be considered a compliance. 
  
  
• Recording CCTV footage of the crowd is a vital part of demonstrating that fish are in good health before a treatment or are not being over-crowded, for example. Overcrowding is a concern for welfare as it causes an increased chance of physical damage to the fish, increased stress and higher oxygen demand.
  
  
• If an RSPCA Assured member experiences difficulty meeting this standard, for example, if their vessel doesn’t have the capability to use CCTV, we encourage them to contact RSPCA Assured, and we will offer advice and support.

* Crowding in this context is when the net is lifted and the fish are held in a smaller volume of water, making it easier to remove them.