Marine finfish and land-based fish health technical working group
On this page
- Executive summary
- Introduction
- Objectives
- Scope
- Specific questions
- FHTWG meetings and activities
- Accomplishments against the objectives, scope and specific questions
- Accomplishments against the specific questions
- Conclusion
- Appendix 1 - List of fish health technical working group members
- Appendix 2 - Terms of reference
- Appendix 3 - Summary of sea lice (Lepeophtheirus salmonis) management in various jurisdictions in Canada and abroad
- Appendix 4 - Comparison of PRV, HSMI, Jaundice Syndrome in various jurisdictions
- Appendix 5 - Presentation by Dr. Craig Stephen on alternate approaches to management of fish health
- Appendix 6 - Final report of the veterinary workshop
- Appendix 7 - Supplemental materials
Executive summary
On June 4, 2019, Fisheries and Oceans Canada (DFO) announced the creation of an Indigenous and Multi-stakeholder Advisory Body (IMAB) and three technical working groups to develop recommendations related to aquaculture management in BC. Among these, the Marine Finfish and Land-based Fish Health Technical Working Group (FHTWG) was tasked to:
- Undertake a review of existing marine finfish aquaculture fish health management regimes internationally, including data collection requirements, standards and management metrics, and corresponding management approaches to fish health;
- Review previous audits and assessments of DFO’s fish health management regime; and
- Recommend improvements to the DFO Pacific Region fish health management regime.
The intent of the reviews and recommendations was to strengthen the environmental performance of salmon aquaculture in BC and to improve fish health outcomes for aquaculture and wild fish in the Pacific Region.
The 12 members of the FHTWG (one resigned before the process was completed) had varied backgrounds, experiences and perspectives towards salmon farming, aquaculture fish health and the risk they both present to wild fish. The FHTWG met on ten occasions (in person meetings and/or teleconference calls) to deliberate and discuss the materials that were compiled and exchanged and to receive presentations on current and alternative approaches to fish-health management from DFO and non-DFO experts. Considerable discussion focussed on specific questions related to on-farm sea lice management, including sea lice conditions of licence, and issues related to Piscine Orthoreovirus (PRV), on farm monitoring for Heart and Skeletal Muscle Inflammation (HSMI) and Jaundice Syndrome, including case definitions and subclinical signs (i.e., not severe enough to present definite or readily observable signs) of these two diseases. Further, a review of DFO’s current case definitions of HSMI and Jaundice Syndrome was conducted by 17 veterinarians and veterinary pathologists, with across Canada and international representation, who attended a separate, two-day workshop (held in January 2020). These veterinarians and veterinary pathologists were tasked with determining if the case definitions in use by DFO were robust and met best international standards/practices, including those of the regulatory frameworks of other salmon producing countries. (The workshop’s report is provided as Appendix 6.)
Generally, the engagement in discussion was strong and participation was broad across all FHTWG members. The scope of discussions on all three assigned tasks included numerous polarized views on both the interpretation of scientific data as well as the appropriate management responses. For the most part, the exchanges did little to alter members’ perspectives and as a consequence, reaching consensus on all issues was not possible. The membership of the FHTWG, and the role of DFO as the co-moderator and Secretariat of the process came under criticism by some members for the perceived potential bias that it might introduce to the process. At one of their last meetings, these participants suggested that, for future consultation/advisory processes, DFO consider more arms-length advice by external stakeholders. Other members expressed the view that DFO science and regulatory expertise is required for meaningful discussion and favoured structured approaches such as those employed by the Canadian Science Advisory Secretariat for the development of science advice to inform improvements to environmental performance of salmon aquaculture in BC.
Based on the reviews they conducted, the FHTWG did not seek to assign a relative rating or ranking to the environmental performance of salmon aquaculture in BC relative to other jurisdictions, but they concurred that there was scope for further improvements in data collection and public reporting, standards and management metrics, and corresponding management approaches to fish health to strengthen the environmental performance and improve fish health outcomes for aquaculture and wild fish in the Pacific Region. Thus, the FHTWG had consensus on the need for more robust science, data collection and data sharing to inform decision-making and regulation of the industry, and increase public transparency and trust. Members supported exploring a more adaptive and performance-based management of the industry with regards to fish health. Consensus existed for the need that regulations governing industry compliance be enforceable in a timely way and that penalties be commensurate with the nature of the non-compliance.
The FHTWG also reached majority agreement on the following specific recommendations for improvement:
Specific recommendations for actions DFO should undertake for its Pacific Marine Aquaculture Finfish Management Regime
- Improve communication of its aquaculture management activities and related science and seek further external advice on the critical elements to be communicated and the best methods to do so;
- Evaluate its approach to adaptive management and improve clarity of its audit program goals, objectives, and implement targeted audits;
- Improve clarity, timeliness, and accessibility of aquaculture data and audit reports for external parties. Further stakeholder engagement on these approaches and targets should be undertaken;
- Explore the fish health benefits of area-based and performance-based management of fish farms. It was recognized that there is an important link between fish health management considerations and the work of the Area-based Management Technical Working Group;
- Establish collaborations with relevant external organizations to augment its internal information holdings on specific fish health issues (e.g., sea lice counts on wild fish);
- Establish measurable indices of fish health applicable to cultured (and wild fish). The likely need for different indices for cultured and wild fish was acknowledged, as was the need to consider the whole disease pathway, epidemiology and effects of infection and disease, fish species, and population/system-level metrics;
- Strengthen its enforcement of aquaculture regulations relating to sea lice and implement appropriate penalties for non-compliance. Consideration should be given to ticketing, fines and, with the appropriate biological evidence to support improved fish health outcomes to mandatory fallow or directed mandatory harvesting of cultured fish;
- Support the development of tools which allow the removal of cultured fish that are performing poorly in such a manner which does not compromise the health and welfare of other net-pen fish; and
- Implement a process to review the conditions of license for all aquaculture facilities so that recommendations for best practices for the management of fish health can be applied to all organizations (e.g., industry, community, government, etc.) growing fish in BC. The review should compare and contrast the conditions of license for all licensed facilities and suggest recommendations which would be appropriate for each type of facility keeping in mind the goal is fish health management regardless of the type of licensed facility.
Specific recommendations regarding the Conditions of Licence (COL) for on-farm sea lice management
- Sea lice COL should be more enforceable, through both specific language and means by which enforcement can occur (e.g., monetary fines, ticketable offences, directed, mandatory fish harvesting etc.);
- Current required levels of sea lice monitoring should be increased and a farm-level sea lice threshold, in addition to a fish-level threshold, should be considered for addition to the COL;
- Pre- and post-treatment sea lice counts should be required so that DFO can better assess the efficacy of specific treatments and monitor for and mitigate against developing resistance;
- Submission of environmental data by farm operators should be included as a requirement to support improved investigation of the causes of sea lice abundance changes;
- Capture of sea lice that are removed by mechanical means; and
- Recognizing that Integrated Pest Management (IPM) in aquaculture and agriculture is a proven strategy to control pests; there should be a stated requirement in all IPM plans related to finfish that non-chemotherapeutant control options will be considered by the licensed veterinarian and preferentially utilized when appropriate and available.
Other recommendations related to improving sea lice knowledge and management
- DFO should conduct spatial and temporal monitoring of wild salmon sea lice and evaluate potential impacts to wild fish survival and the effectiveness of sea lice management of farmed fish;
- Any wild salmon sea lice monitoring results conducted by industry or any other organization under a DFO Scientific Permit should be submitted to the Department and made publicly available;
- DFO should conduct/support research to determine the viability of sea lice following treatment with hydrogen peroxide and following removal via bath or mechanical treatments if they are not captured and disposed by the technology; and
- When setting conditions for pathogen and pest management, DFO should consider standards developed by independent, third-party international certification bodies for consumer-facing marketing of aquaculture products, as well as, farmed animal welfare standards set by the World Organization of Animal Health and the National Farmed Animal Care Council of Canada. International best practices should be adopted as the minimum acceptable standard.
Specific recommendations for actions DFO should undertake for its on-farm fish health management of PRV, HSMI and Jaundice Syndrome
- Conduct and support PRV challenge studies for all species of Pacific salmon, including looking at the physiological impact to infected and diseased fish as this could provide key information regarding the potential of a virus and associated diseases to have an impact on the protection and conservation of a particular species; and
- Review its current case definitions for HSMI and Jaundice Syndrome to ensure they are robust and conform to international best practices.
Other recommendations for actions DFO should undertake
- In collaboration with the Canadian Food Inspection Agency, DFO should implement targeted monitoring for improved early detection of emerging diseases, as well as sub-lethal or pre-clinical signs of disease, as appropriate.
Major points of disagreement among the FHTWG related to PRV in BC and its role in disease development, the extent to which subclinical signs of disease are present and a predictor of health outcomes, the role of environmental conditions in sea lice development and transmissivity between aquaculture and wild populations, and the extent to which poorly performing aquaculture fish provide insight into the health of the population or risk to wild salmon health. A section of this report is dedicated to these, and other, points of disagreement among the FHTWG. It includes the varying perspectives of FHTWG members on these topics and could serve as context for informing future research investments to improve the knowledge base and lower uncertainties associated with current scientific information on the environmental performance and health of aquaculture and wild fish in BC.
Given its broad scope and limited term, the FHTWG acknowledges that more work is required to fully deliver on its mandate. A number of members recommend that DFO support an ongoing forum for this purpose. Finally, the FHTWG appreciates the responsiveness of DFO to incorporating some of its recommendations in “real time” into the 2020 Conditions of Licence.
Disclaimer
The Fish Health Technical Working Group wish to acknowledge the contributions and expertise of the First Nations delegates who have participated in meetings, with the understanding that the contents and recommendations of this report are not endorsed by the BC First Nations Fisheries Council or any individual First Nations including the First Nations of whom the participants are members.
Introduction
On June 4, 2019, the Honourable Jonathan Wilkinson,Minister of Fisheries and Oceans Canada (DFO or the Department), announced that the Department would establish an Indigenous and Multi-Stakeholder Advisory Body (IMAB). This group would be chaired by DFO’s Deputy Minister, Timothy Sargent, and be asked to provide recommendations to DFO for strengthening the environmental performance of aquaculture in British Columbia (BC). Three Technical Working Groups, each focused on a key aquaculture issue that had been identified for improvement and/or enhanced collaboration, were created to support the work of the IMAB. Both the IMAB and the Technical Working Groups were to be inclusive and comprised of representatives or delegates of the Province of BC, Indigenous communities, environmental organizations, and the aquaculture industry. DFO staff participated in a secretariat role and provided information to the group in an ex-officio capacity. The focus of each of the respective Technical Working Groups was:
- Area-based approaches to aquaculture management;
- Alternative finfish aquaculture production technologies; and
- Marine finfish and land-based fish health.
All three Technical Working Groups were originally scheduled to complete their mandates by December 2019, but this date was subsequently extended to end of March 2020 to provide opportunity for more detailed deliberations and advice development. Final reports from each Technical working Group were submitted in May, 2020.
This report focusses on the recommendations and discussions of the Marine Finfish and Land-based Fish Health Technical Working Group (FHTWG). The FHTWG was comprised of two co-chairs, 12 initial members (one member resigned just before the process was completed), eight ex officio Government members from DFO and the CFIA, and three administrative support staff from DFO (Appendix 1). The Terms of Reference for the FHTWG, which were finalised and endorsed by its members at their first meeting on September 13, 2019, established their Guiding Principles, Objectives, Scope, Timeframe, Governance, and Responsibilities (Appendix 2). Information on additional meeting materials such as meeting agendas, minutes, background documents and selected publications can be found in Appendix 7.
Objectives
The objectives of the FHTWG were to:
- Provide a forum for the participants to discuss actions underway and planned by DFO related to changes to aquaculture management, and to allow participants to provide advice and to share information to help inform the Department’s decision-making.
- Promote dialogue and improve understanding of the complexities of aquaculture management, joint responsibilities, and respective roles of the FHTWG participants.
- Identify opportunities for collaboration and partnerships relating to the management of aquaculture in BC.
Scope
The scope of the FHTWG included the health and welfare of cultured fish and any spillover effect (e.g., infection or disease from viruses, bacteria, parasites, etc.) which cultured fish may have on the health of wild fish stocks. The FHTWG was tasked to:
- Undertake a review of existing marine finfish aquaculture fish health management regimes internationally, including data collection requirements, standards and management metrics, and corresponding management approaches to fish health;
- Review previous audits and assessments of DFO’s fish health management regime; and
- Recommend improvements to the DFO Pacific Region fish health management regime, which would include:
- Evaluating the parameters and justifications used to measure fish health;
- Recommending standards and metrics for tracking and reporting, and enhancements to the rigour and transparency of data;
- Recommendations for creating “greater certainty” in fish health, reducing risk, or mitigating potential adverse outcomes;
- Recommendations for how to better detect, respond to, and manage fish health; and
- Recommending more clear rules for compliance, and penalties for non-compliance.
Specific questions
In addition to the general objectives and scope of work outlined above, the FHTWG was also assigned specific technical questions including:
On-farm sea lice management
- What recommendations does the FHTWG have for the Department to strengthen its sea lice Conditions of Licence (COL) in 2020 and 2022Footnote 1
PRV-HSMI-Jaundice Syndrome
- What recommendations does the FHTWG have for the Department regarding an on-farm monitoring program for Heart and Skeletal Muscle Inflammation (HSMI) and Jaundice Syndrome? What specific testing might the Department consider to detect subclinical signs (i.e., sign is not severe enough to present as definite or readily observable) of HSMI and Jaundice Syndrome and at what frequency?
- If subclinical signs of HSMI or Jaundice Syndrome are detected on farms, what are the recommended management actions?
- If hatchery salmon test positive for Norwegian or Icelandic strains of Piscine Orthoreovirus (PRV), what does the FHTWG recommend as action? What would be the threshold for action (i.e., how many fish would need to test positive to elicit a response)?
FHTWG meetings and activities
To deliver on its mandate, the FHTWG convened ten in-person and/or teleconference meetings. Members requested information and presentations from DFO and non-DFO experts and they compiled and exchanged materials to support their deliberations via email. As well, the FHTWG convened a 2-day workshop of 17 veterinarians and veterinary pathologists (held in January 2020) to review DFO’s current case definitions of two PRV-associated diseases (HSMI and Jaundice Syndrome) to ensure they were robust and met best international standards/practice, including those of the regulatory frameworks of other salmon producing countries. Prior to the completion of this final FHTWG report, an interim progress report was delivered to and the FHTWG sought direction from the IMAB members in February 2020.
Whereas general improvements to DFO’s current aquaculture and wild fish health management regimes were considered, most of the FHTWG deliberations focused on the management of specific pathogens and pests (i.e., addressing the technical questions with which they were tasked). Due to time constraints, there was limited opportunity to explore management actions that would improve health outcomes for aquaculture fish resulting from factors such as climate change or environmental degradation or health outcomes of wild fish from interactions with aquaculture fish at specific life history stages or in specific habitats.
The members of the FHTWG had varied backgrounds, experiences and perspectives towards fish health and the risk it presents to wild fish. Observers were also allowed to attend. Discussions at the meetings and through follow-up emails had broad engagement, and they were frequently broad-ranging and invariably challenging. The scope of discussions included numerous polarized views on both interpretation of scientific data and appropriate management recommendations. Specific details of a number of points of polarization and disagreement are included in this report and in associated documentation as context for future follow-up actions or discussions.
Accomplishments against the objectives, scope and specific questions
With respect to the Objectives and Scope outlined above, the FHTWG meetings provided participants with a forum to discuss actions underway in the DFO Pacific Region with respect to aquaculture fish health management, to share information that informed discussions, and to develop advice to DFO. Their deliberations were assisted by presentations that provided information on the current fish health management regimes that exist in both the Canadian Food Inspection AgencyFootnote 2 (CFIA) and the DFO Pacific RegionFootnote 3. In order to situate the current fish health management regimes into an international context, additional presentations and compilations of international approaches to the monitoring and management of specific fish health management issues were also considered (Appendices 3-4). Additionally, a presentation on alternative approaches to the management of aquaculture and wild fish health was considered (Appendix 5), but there was insufficient time within the mandate of the FHTWG to fully explore the potential advantages of such an approach or how it might practically be implemented in Canada’s Pacific region. Nonetheless, some members expressed interest in DFO piloting the application of a broader and holistic conceptual approach to aspects related to fish health and an aquatic animal health management framework. Inform consideration of the implementation of Area-based aquaculture management.
Collectively, the information and exchanges highlighted the complexities of aquaculture fish health management, they furthered understanding of the roles and responsibilities of the various participants and internal DFO processes, and led to identification of opportunities for enhanced collaboration among various stakeholder groups with the potential to strengthen health management outcomes.
Full consensus on the specific questions posed to the group was not achieved. Very broadly, members supported increased research and regulatory oversight/enforcement, as well as a more holistic approach to aquaculture management. Further areas of general consensus, as well as topics where consensus was not reached, are documented in the remainder of this report.
Review of the DFO Pacific marine aquaculture finfish management regime
The FHTWG reviewed the literature available on DFO’s website regarding aquaculture management, the description of its Fish Health Audit and Intelligence Program, the results of a 2017 audit conducted by AusVet, the 2018 Salmon Farming Report by the Commissioner of the Environment and Sustainable Development Canada, and the progress that DFO has subsequently accomplished implementing audit recommendations. Consensus was only occasionally achieved due to the wide range of views and strongly divergent opinions, but the majority of the FHTWG members agreed on several specific actions that DFO should undertake for its Pacific Marine Aquaculture Finfish Management Regime.
Specific recommendations for actions DFO should undertake for its Pacific Marine Aquaculture Finfish Management Regime
- Improve communication of its aquaculture management activities and related science and seek further external advice on the critical elements to be communicated and the best methods to do so;
- Evaluate its approach to adaptive management and improve clarity of its audit program goals, objectives, and implement targeted audits;
- Improve clarity, timeliness, and accessibility of aquaculture data and audit reports for external parties. Further stakeholder engagement on these approaches and targets should be undertaken;
- Explore the fish health benefits of area-based and performance-based management of fish farms. It was recognized that there is an important link between fish health management considerations and the work of the Area-based Management Technical Working Group;
- Establish collaborations with relevant external organizations to augment its internal information holdings on specific fish health issues (e.g., sea lice counts on wild fish);
- Establish measurable indices of fish health applicable to cultured (and wild fish). The likely need for different indices for cultured and wild fish was acknowledged, as was the need to consider the whole disease pathway, epidemiology and effects of infection and disease, fish species, and population/system-level metrics;
- Strengthen its enforcement of aquaculture regulations relating to sea lice and implement appropriate penalties for non-compliance. Consideration should be given to ticketing, fines and, with the appropriate biological evidence to support improved fish health outcomes, to mandatory fallow or directed mandatory harvesting of cultured fish;
- Support the development of tools which allow the removal of cultured fish that are performing poorly in such a manner which does not compromise the health and welfare of other net-pen fish; and
- Implement a process to review the conditions of license for all aquaculture facilities so that recommendations for best practices for the management of fish health can be applied to all organizations (e.g., industry, community, government, etc.) growing fish in BC. The review should compare and contrast the conditions of license for all licensed facilities and suggest recommendations which would be appropriate for each type of facility keeping in mind the goal is fish health management regardless of the type of licensed facility.
Some key points of divergence and subjects for further discussion were:
- There were different perspectives among members on the relative importance of “poor performers” as: contributing to sea lice numbers on farms, an indicator of health of the population, and potential use as “fish health sentinels” for subclinical signs of disease, and/or source of infection to either farmed or wild fish;
- There was disagreement on whether additional investment of government resources into aquaculture fish health management was warranted with some members suggesting the present level of oversight is sufficient given the generally high compliance of the industry in BC. Others disagreed that compliance was high, and recommended an increased level of monitoring and oversight to be required to ensure aquaculture practices remain sustainable in the face of emerging risks and increased public expectations of transparency and reporting by regulatory authorities;
- There was disagreement on whether DFO should manage Caligus sp. ofsealice (e.g., require monitoring and reporting) in addition to the Lepeophtheirus salmonis sea lice and whether sea lice should be monitored in Pacific herring populations;
- There was disagreement on the best management actions to quickly and effectively administer penalties for violations of conditions of license – especially, in the absence of some suggested regulatory tools such as expedited or mandated harvesting or fines;
- Although there was general support for a DFO-hosted publically accessible database that would incorporate data from all sources on aquaculture and wild fish health, there were concerns raised regarding the technical challenges of encompassing data collected from multiple sources into a unified database, and the significant consideration that would need to be given to quality control/assurance, collection methodology and survey design given their potential to distort and/or influence the use and interpretations of the compiled data. Nonetheless, there was broad support for the compilation and dissemination of a list of the variously publicly available data sources;
- A number of members expressed concerns that DFO engagements with First Nations and stakeholders have been deficient and should be more inclusive of additional stakeholders. Therefore, a thoughtful review of engagement strategies with First Nations and stakeholders should be undertaken;
- Extensive discussions on the relative robustness of the aquaculture management regime in BC compared to other international salmon farming jurisdictions were limited to PRV, Jaundice Syndrome, HSMI and sea lice (see Appendices 3 and 4). Other aspects were not compared or discussed; and
- FHTWG members agreed that further improvements to Canada’s current management regime were desirable.
Improvements to communication, data sharing and research collaborations
A recurring concern many FHTWG participants directed at DFO was its perceived lack of transparency and deficiency in communications pertaining to aquaculture in BC, although participants did acknowledge financial and staffing constraints. As noted above, the FHTWG recommends that DFO improve its current communication regarding aquaculture with external stakeholders. Several specific suggestions were offered to address this recommendation:
- Hire an external consultant to audit and assess DFO’s current aquaculture communication strategy and to provide recommendations for improvement. The audit would include, but not be limited to, financial and staffing resources, policies, linkages with the CFIA, and technology challenges or gaps, among others;
- Concurrently, the audit would engage with multiple stakeholders through various means to determine their interests in terms of data sharing, tailored information updates, and collaboration on scientific research projects and results; and
- Based on the findings of both these activities, DFO should make appropriate improvements that meet different user-groups’ needs as much as possible.
Another recurring critique from many members was the lack of ease of access to information, the lack of “real-time” updates or access to the most current data and information, and the “sole-source” of the data (i.e., only from Departmental processes). There was strong support for DFO to move towards an open-sourced (i.e., publically-available) database for fish health-related information to promote data-sharing among all parties, and to take advantage of existing programs, with an emphasis on real-time data from multiple sources (or as close to this as possible, as some data restrictions might exist, for example, testing results for CFIA-regulated diseases). For example, it was suggested that data collected from scientific collection permits be made available to the Aquaculture Management team to help inform decisions and allow increased public reporting/transparency.
With regards to the recommendation for increased research and expanded data collection, there were a few specific suggestions, with a focus on gaining more knowledge about the health of farmed and wild fish. There should be increased monitoring of the health of farmed, wild, and enhancement fish. This monitoring needs to be appropriately designed to provide insights into fish health (e.g., consider ecological context, seasonality, life stage, species, transmission pathways, etc.), and should piggyback on the existing collection of fish under other programs (e.g., scientific collection permits). Importantly any assessment of health/disease for different populations of fish (i.e., cultured vs. wild) needs to consider the different environments and use different techniques. For example, detection of clinical disease in wild fish can be difficult, but possible with an effective monitoring program and may answer important epidemiological questions such as the role of disease in predator/prey interactions. Therefore, some members of the FHTWG recommended consideration of population impacts, resulting from any degree of physiologic compromise, need to be different for farmed and wild fish given the significant differences in their life histories. The welfare of both farmed and wild fish must be considered and prioritized for both ethical and humane reasons (e.g., minimizing the unnecessary stress and death of fish), and it was recommended that animal welfare experts be closely involved in these consultations.
Accomplishments against the specific questions
On-farm sea lice management
To inform recommendations on improvements to the 2020 and 2022 sea lice Conditions of Licence (COL), the FHTWG was provided an overview of sea lice science and current management in BC, a summary of DFO sea lice compliance challenges, and a compilation of sea lice monitoring and management activities in salmon aquaculture in various jurisdictions in Canada and abroad (Appendix 3).
Based on this input, the FHTWG held extensive discussions on developing advice for DFO Aquaculture Management on how to practically strengthen and improve the on-farm management of sea lice in BC. A number of areas of agreement were reached for proposed changes to the COL.
Specific recommendations regarding the Conditions of Licence (COL) for on-farm sea lice management
- Sea lice COL should be more enforceable, through both specific language and means by which enforcement can occur (e.g., monetary fines, ticketable offences, directed expedited and mandatory fish harvesting etc.);
- Current required levels of sea lice monitoring should be increased and a farm-level sea lice threshold, in addition to a fish-level threshold, should be considered for addition to the COL;
- Pre- and post-treatment sea lice counts should be required so that DFO can better assess the efficacy of specific treatments and monitor for and mitigate against developing resistance;
- Submission of environmental data by farm operators should be included as a requirement to support improved investigation of the causes of sea lice abundance changes;
- Capture of sea lice that are removed by mechanical means; and
- Recognizing that Integrated Pest Management (IPM) in aquaculture and agriculture is a proven strategy to control pests; there should be a stated requirement in all IPM plans related to finfish that non-chemotherapeutant control options will be considered by the licensed veterinarian and preferentially utilized when appropriate and available.
Other recommendations related to improving sea lice knowledge and management:
- DFO should conduct spatial and temporal monitoring of wild salmon sea lice and evaluate potential impacts to wild fish survival and the effectiveness of sea lice management of farmed fish;
- Any wild salmon sea lice monitoring results conducted by industry or any other organization under a DFO Scientific Permit should be submitted to the Department and made publicly available;
- DFO should conduct/support research to determine the viability of sea lice following treatment with hydrogen peroxide and following removal via bath or mechanical treatments if they are not captured and disposed by the technology; and
- When setting conditions for pathogen and pest management, DFO should consider standards developed by independent, third-party international certification bodies for consumer-facing marketing of aquaculture products, as well as, farmed animal welfare standards set by the World Organization of Animal Health and the National Farmed Animal Care Council of Canada. International best practices should be adopted as the minimum acceptable standard.
Several of these areas of agreement were subsequently reflected in the 2020 Sea Lice Conditions of Licence (COL) which DFO issued on February 29, 2020Footnote 4. The new COL now have increased requirements for monitoring and reporting of sea lice numbers, some of which are for the purpose of assessing treatment efficacy and preventing drug/pesticide resistance. There is more specific language regarding mitigation and timelines required following sea lice exceedances, which in turn should allow for increased enforceability following non-compliance.
Some key points of divergence and subjects for further discussion include:
- There was strong disagreement on the 2020 licence condition that allows the sea lice threshold to be exceeded for a period of time during wild salmon mitigation;
- There was a range of perspectives discussed regarding the use of chemotherapeutants to control sea lice. Several were of the view that non-chemotherapeutant approaches should be prioritised in treating sea lice infestations, whereas others supported an Integrated Pest Management (IPM) approach, which considers many factors including fish welfare and utilizes both chemotherapeutant and non chemotherapeutant approaches;
- There was disagreement on sea lice thresholds particularly with respect to their ecological consequences as well as potential impacts to wild fish (including treatment options) and the use of the precautionary approach;
- There was significant divergence in opinion as to what constitutes an appropriate level of monitoring, based on a finite number of resources, and with respect to who should be responsible for the costs of monitoring;
- There was disagreement on the reliance of DFO (and other entities) on its practicing veterinarians, given both their designation as a self-regulated profession and their professional obligations to their clients and patients;
- Considerable environmental data are currently collected onsite by industry, and some data are continuous and in real-time, but there were differences in opinion regarding best practices for collecting and reporting environmental data, due to the often non-continuous nature of these data (i.e., variations in the time and frequency of measurements, rates of change in measured parameters, etc.);
- Whereas there was agreement on the aspirational goal to capture 100% of all viable sea lice dislodged following mechanical/bath treatments, there was disagreement on whether the technology to perform this task currently exists or if there is a necessity to capture dislodged sea lice if they are not viable. Some members thought that testing for non-viability should be a requirement for continued use of such treatment techniques; and
- There was agreement on that research on cleaner fish in the Pacific Region should be undertaken but there was disagreement on whether industry, government or other body should fund this research.
Additionally, whereas there was general agreement that there would be value in incorporating relevant fish health information from all potential sources into a single publicly accessible database, there were unresolved deliberations about how quality control and assurance could be achieved.
Importantly, although discussion that ethical requirement to consider the health and welfare of farmed fish, and the need for veterinarians to choose appropriate treatments to support that goal, should be considered in all aspects of management, there was insufficient time for the FHTWG members to provide consensus advice on how this might best be achieved.
There was a recognition that the DFO updated its 2020 conditions of licence incorporating some of the preliminary recommendations of the FHTWG in near ‘real-time’ and that it has committed to reissuing licenses again in 2022 following further consideration of the final FHTWG recommendations and additional consultation with First Nations, ENGOs, Industry and other stakeholders.
On farm fish health management – PRV, HSMI, Jaundice Syndrome
To inform recommendations to DFO related to the specific questions posed to the FHTWG on monitoring and management of Piscine Orthoreovirus (PRV), Heart and Skeletal Muscle Inflammation (HSMI), and Jaundice Syndrome (referred to by some as “jaundice/anemia”), reviews were conducted of the current DFO fish health management regimeFootnote 5, a compilation of monitoring and management requirements specific to PRV, and HSMI and Jaundice Syndrome in various aquaculture jurisdictions around the world (Appendix 4).
The reviews show that, among the global jurisdictions assessed, BC is the only one which has instituted reporting requirements targeted at Jaundice Syndrome and/or HSMI. No other jurisdiction has a regulatory requirement for monitoring and reporting the sub-genotype of PRV found in the eastern Pacific. For a period of time Norway required national reporting of HSMI until it became ubiquitous in its waters.
At the request of the FHTWG, a workshop of 17 aquatic veterinarians and veterinary pathologists was convened to review the DFO case definitions for HSMI and Jaundice Syndrome. The FHTWG membership nominated qualified veterinarians to participate in the workshop, and elected an independent facilitator from among a selection of candidates who were also nominated by the FHTWG members. Ultimate selection of workshop participants was based on their independent professional expertise and not as representatives of any organization or regulatory agency. The 2-day workshop was conducted in January 2020 and a report of the participants’ findings (Appendix 6) was made available to the FHTWG in early March 2020, prior to their final meeting. The workshop did not have unanimous consent on issues, but there was a strong majority support by those participating in the workshop, on every recommendation. Workshop participants recommended an additional classification for Jaundice Syndrome but did not recommend significantly changing the case definitions currently applied by DFO veterinarians.
Workshop participants recommended a more stringent case definition for both diseases and a more robust framework for the future detection and classification of HSMI in BC. This was in contrast to the concerns expressed by a number of members of the FHTWG that the historic HSMI case definition, requiring clinical signs and/or mortality, was unjustifiably stringent and therefore missed diagnosing some actual occurrences of HSMI. The workshop report emphasized the need for, and importance of, understanding the pathogenesis of each disease diagnosis in all species of wild salmon and additionally generally noted the importance of conducting research on the virulence factors of PRV and other potential contributing disease agents, and the influence of dynamic environmental and ecological processes to fill identified knowledge gaps.
Based on this input, the FHTWG held extensive discussions on developing advice for DFO on several considerations related to fish health management. Additionally, it was generally agreed that there is a continued need for the evaluation and reporting of potential new and emerging diseases including notifying the CFIA for confirmation and reporting of listed diseases, and for increased collaboration between DFO and the CFIA with regard to researching new and emerging diseases. A number of areas of agreement were reached and recommendations proposed for actions DFO should undertake for its on-farm fish health management of PRV, HSMI and Jaundice Syndrome.
Specific recommendations for actions DFO should undertake for its on-farm fish health management of PRV, HSMI and Jaundice Syndrome
- Conduct and support PRV challenge studies for all species of Pacific salmon, including looking at the physiological impact to infected and diseased fish as this could provide key information regarding the potential of a virus and associated diseases to have an impact on the protection and conservation of a particular species; and
- Review its current case definitions for HSMI and Jaundice Syndrome to ensure they are robust and conform to international best practices.
Other recommendations for actions DFO should undertake
- In collaboration with the Canadian Food Inspection Agency, DFO should implement targeted monitoring for improved early detection of emerging diseases, as well as sub-lethal or pre-clinical signs of disease, as appropriate.
Significant debate and discussion among the FHTWG related to PRV in BC and its role in disease development, the extent to which subclinical signs of disease are present and a predictor of health outcomes and/or pathogen-transmission potential, the role of environmental conditions in disease development and transmissivity between aquaculture and wild populations, and the extent to which poorly performing aquaculture fish provide insight into the health of the population or risk to wild salmon health generated polarized perspectives and identified additional issues requiring further consideration, including:
- Some FHTWG participants contested the findings of the veterinary workshop including their determination that pre-clinical/sub-clinical states were not relevant for diagnostic and regulatory purposes;
- There were divergent views among FHTWG members on reported distinctions between endemic vs exotic variants of PRV, and the ability of documented methodologies for determining disease etiology, origin, and virulence. The FHTWG did not agree on what constitutes a “foreign strain” of PRV;
- There was disagreement as to the value and necessity of ongoing surveillance of PRV strains in BC. Suggestions were made to monitor for any change in PRV-related disease presentations as an early and reliable indicator of a change in virulence which would prompt the need for further investigation including genetic sequencing;
- There was agreement that a discussion should ensue on establishing measureable indices of fish health. However, there was considerable discussion and unresolved actions on how to proceed with establishing such indices of fish health, and no discussion on what the indices should be and if/how they might apply differently to wild and cultured fish;
- Despite the broad support for further research on PRV through lab-based experimental challenges with PRV and determination of any physiologic impacts on all species of Pacific salmon, there was disagreement on the applicability of results obtained from such experiments to wild fish;
- There was considerable and unresolved debate on the perceived biases among FHTWG members;
- There was significant debate among FHTWG members on the potential consequence of PRV, HSMI and Jaundice Syndrome on the health of wild fish populations;
- The validity of published PRV challenge studies conducted by DFO scientists was a subject of considerable unresolved debate, as was the discussion of what diseases and infective agents should be screened and in which populations (farmed vs wild vs enhanced); and
- Additionally, there is a requirement to collect additional fish health and environmental data to support DFO’s targeted auditing for HSMI and Jaundice Syndrome. Nonetheless, some of FHTWG members considered that these changes did not sufficiently address concerns.
Conclusions
The formation of the FHTWG is acknowledged by its members as an important step in the DFO’s commitment to improving engagement on and the sustainability of aquaculture practices and the protection of wild fish stocks in BC. Given its broad scope and limited term, the FHTWG acknowledges that more work is required to fully deliver on its mandate. Most members recommend continued engagement of relevant parties, in some manner, to provide their perspective on monitoring and regulation of aquaculture in BC beyond the duration of this FHTWG’s mandate. Should this recommendation be accepted, the following guidance is provided:
- Greater consideration should be given to the makeup of the membership. DFO should attempt to balance representation from industry, government, academia, and environmental non-governmental organizations (ENGOs), as well as other potential interlocutors. Specifically, the FHTWG members highlighted the need for multiple First Nations’ voices at the table to ensure the full diversity of First Nations perspectives within the Pacific Region are represented. In addition, it was stated numerous times that FHTWG members were delegates of First Nations groups, but were neither representatives nor spokespeople. As this is a technical working group, those with Traditional Ecologic Knowledge and/or scientific expertise relevant to aquaculture and wild fish in British Columbia should be consulted;
- Allow the membership of the group to make decisions on internal working group governance including chair, meetings, agendas, secretariat, codes of conduct, and other roles required to deliver on its mandate. This may include either group consensus for a single party to assume each role, provide for rotation of roles between members, or allow the membership to seek external parties for these roles. Some members of the current process were critical of the fact that it was led and chaired by DFO and not an independent facilitator. Whereas other members expressed that DFO should lead and chair the process, given their responsibility for the governance and regulation of aquaculture in B.C, and their public accountability;
- Allow the membership to establish the number, duration, and format of meetings, as well as establish clear focus and goals required to achieve their mandate;
- Provide appropriate resources, including financial support, for all members to fully attend and participate;
- Allow for significant time to establish a group culture that will facilitate future dialogue and cooperation; and
- It should be recognized that such a forum would have a different objective from and will not replace existing mandated mechanisms for ongoing DFO engagement and consultations.
Members encountered significant challenges which prohibited better outcomes to this process. The two biggest challenges were: a) the short timeframe members were provided in which to build a common understanding on broad and complex issues; and b) real and perceived biases among the members that led to difficult and, frequently challenging discussions, and precluded full consensus on many recommendations/decisions. Nonetheless, a majority of members supported the recommendations outlined in this report and appreciate that some of these recommendations were incorporated in near “real time” into the 2020 Conditions of Licence for marine finfish operators in BC.
Lastly, the varying perspectives of the FHTWG members could serve as context for informing future research investments to improve the knowledge base and lower uncertainties associated with current scientific information on the environmental performance and health of aquaculture and wild fish in BC.
Appendix 1 - List of fish health technical working group members
Fish Health Technical Working Group (FHTWG) delegates
Name | Affiliation | Role | |
---|---|---|---|
Dr. Carmel Lowe | DFO, Pacific, Science | Co-Chair (Ex-officio) | carmel.lowe@dfo-mpo.gc.ca |
Dr. Penny Greenwood | Canadian Food Inspection Agency | Co-Chair (Ex-officio) | penny.greenwood@canada.ca |
Name | Affiliation | Role | |
---|---|---|---|
Chad Fuller | Okanagan Nation Alliance | Delegate | cfuller@syilx.org |
Larry Johnson | Nuu-chah-nulth Seafood Development Corporation | Delegate (Alternate Jared Dick ) | larry.j@ncnseafood.com jared.dick@nuuchahnulth.org |
Richard Holmes | Cariboo Envirotech, Upper Fraser Fisheries Conservation Alliance | Delegate | carenvir@wlake.com |
Dr. Fred Kibenge | University of PEI, Atlantic Veterinary College | Delegate | kibenge@upei.ca |
John Werring | David Suzuki Foundation | Delegate (Alternate Kilian Stehfest) | jwerring@davidsuzuki.org kstehfest@davidsuzuki.org |
Sharon DeDominicis | Mowi Canada West | Delegate (Alternates Dr. Mark Sheppard; Dr. Alexandra Eaves; or Dr. Kathleen Frisch) | Sharon.DeDominicis@mowi.com svsbook@shaw.ca; Alexandra.eaves@gmail.com; kathleen.frisch@cermaq.com |
Meghan Mills | Mowi Canada West | Delegate | Meghan.Mills@mowi.com |
Dr. Brad Hicks | Aboriginal Aquaculture Association | Delegate | bhicks@direct.ca |
Dr. Andrew Bateman | Pacific Salmon Foundation | Delegate (alternate Dr. Emiliano Di Cicco) | andrew.w.bateman@gmail.com Emiliano.DiCicco@dfo-mpo.gc.ca |
Dr. Anthony Farrell | University of British Columbia | Delegate | farrellt@mail.ubc.ca |
Dr. Michael Pawlik | BC Ministry of Agriculture, Animal Health Centre | Delegate (Alternate Dr. Chelsea Himsworth) | Michael.Pawlik@gov.bc.ca Chelsea.Himsworth@gov.bc.ca |
Name | Affiliation | Role | |
---|---|---|---|
Dr. Kim Klotins | Canadian Food Inspection Agency | Ex-officio | kim.klotins@canada.ca |
Dr. Kristi Miller-Saunders | DFO, Pacific, Science | Ex-officio | kristi.miller-saunders@dfo-mpo.gc.ca |
Dr. Jay Parsons | DFO, NHQ, Aquaculture, Science | Ex-officio (Alternate Dr. Sunita Khatkar) | Jay.Parsons@dfo-mpo.gc.ca sunita.khatkar@dfo-mpo.gc.ca |
Dr. Zac Waddington | DFO, Pacific, AMD | Ex-officio (Alternate Dr. Sonja Saksida, Dr. Derek Price) | zac.waddington@dfo-mpo.gc.ca sonja.saksida@gmail.com |
Adrienne Paylor | DFO, Pacific, AMD | Ex-officio (Alternate Kerra Shaw) | Adrienne.paylor@dfo-mpo.gc.ca kerra.shaw@dfo-mpo.gc.ca |
Roderick Haesevoets | DFO, NHQ, APD , Stewardship | Ex-officio | roderick.haesevoets@dfo-mpo.gc.ca |
Dr. Kyle Garver | DFO, Pacific, Science | Ex-officio | kyle.garver@dfo-mpo.gc.ca |
Dr. Simon Jones | DFO, Pacific, Science | Ex-officio | simon.jones@dfo-mpo.gc.ca |
Name | Affiliation | Role | |
---|---|---|---|
Anoma Patirana | DFO, Pacific, AMD | Secretariat | Anoma.Patirana@dfo-mpo.gc.ca |
Ginny Van Pelt | DFO, Pacific, AMD | Secretariat | Ginny.VanPelt@dfo-mpo.gc.ca |
Dr. Laura Sitter | DFO, Pacific, AMD | Secretariat | Laura.Sitter@dfo-mpo.gc.ca |
Appendix 2 - Terms of Reference
Marine finfish and land-based fish health technical working group – Draft terms of reference for discussion
Background and purpose
The Minister of Fisheries and Oceans Canada (DFO) announced on June 4, 2019, a series of measures related to the transformation of aquaculture management.
This document outlines the proposed structure and function of the Marine Finfish and Land-Based Fish Health Technical Working Group (TWG) to support the development of new and transformative approaches to the management of aquaculture in the Pacific Region.
Guiding principles
The TWG serves the objective of delivering concrete proposals for actions, guided by the following principles:
- Recommendations are developed and assessed using the best available science and evidence.
- Discussions are informed by a range of policy and technical/scientific expertise in the relevant areas under consideration.
- Recommendations are developed and assessed based on their potential effectiveness in improving the management of aquaculture, recognizing that management can and should adapt over time.
- TWGs will work in a spirit of collaboration and consensus, but will not be required to reach full consensus around any particular proposal.
Objectives
The main objectives of the Working Group will be to:
- Provide a forum for the participants to discuss actions underway and planned by the federal government related to aquaculture management transformation, and to allow participants to provide advice and to share information to help inform government decision-making.
- Promote dialogue and improve shared understanding of the complexities of aquaculture management transformation, shared responsibilities, and respective authorities of the TWG participants.
- Identify opportunities for collaboration and partnership that can advance the collective improvements which can be made relating to the management of aquaculture in the Pacific Region.
- The specific tasks of the Fish Health (the scope of fish health includes the health and welfare of cultured fish (including infection, disease, viruses, bacteria, parasites, etc.) or any spillover effect which cultured fish may have on the health of wild fish stocks) TWG will be as follows:
- Undertake a review of existing marine finfish aquaculture fish health management regimes internationally, including data collection requirements, standards and management metrics, and corresponding management approaches to fish health;
- Review previous audits and assessments of DFO’s fish health management regime;
- Make recommendations which could improve to using the best possible standards to transforming Pacific Region’s fish health management regime, which could include:
- Looking at what is measured and why
- Recommending standards and metrics to be used in tracking and reporting and enhancements to the rigor and transparency of data;
- Recommendations for creating ‘greater certainty’ in fish health, reducing risk, or mitigating potential adverse outcomes;
- Recommendations as to how to better detect, respond to and manage fish health;
- Recommending more clear rules for compliance and penalties for noncompliance
Timeframes
The TWG will identify and propose actions that are both immediate and longer term. The proposed timeframe is as follows:
August meeting:
- Committee introductions;
- Review and respond to draft Terms of Reference;
- Logistics and organization which includes: respond to proposed tasks and time frame, allocate any tasks, discussion of topics/categories for final recommendations, identification of additional questions/expertise/analysis required, initial identification of any potential interim recommendations which would require work prior to September meeting; and
- Plan for review of existing marine finfish aquaculture fish health management regimes internationally including: data collection requirements, standards and management metrics, and corresponding management approaches to fish health; and review of previous audits and assessments of DFO’s fish health management regime.
September meeting:
- Review and discuss background materials and discuss approaches for recommendations.
October meeting: Formulate approach for recommendations.
- Make recommendations which could improve to using the best possible standards to transforming Pacific Region’s fish health management regime, which could include:
- Looking at what is measured and why;
- Recommending standards and metrics to be used in tracking and reporting and enhancements to the rigor and transparency of data;
- Recommendations for creating ‘greater certainty’ in fish health, reducing risk, or mitigating potential adverse outcomes;
- Recommendations as to how to better detect, respond to and manage fish health;
- Recommending more clear rules for compliance and penalties for non-compliance
November meeting:
- Finalize recommendations.
- Interim recommendations – will be made by September 13, 2019.
- Final recommendations – will be made by November 15, 2019.
- Discuss future collaborations and partnerships.
Governance and membership
The TWG will consist of delegates from various Indigenous and stakeholder groups: Indigenous communities, environmental organizations, the aquaculture industry sectors (marine finfish, shellfish, and freshwater/land-based), the Union of BC Municipalities, academia and the Government of British Columbia.
The TWG will be chaired by a senior official from DFO, with ex-officio participation of senior federal officials.
The TWG secretariat will report to the Indigenous and Multi-stakeholder Advisory Body (IMAB), chaired by the Deputy Minister of DFO, on the discussions that were held and the recommendations made, noting the degree of support or divergence among members for advice on different issues.
Additional observers are welcome to listen to discussions; however, participation is limited to members.
Responsibilities of participants
Review circulated information.
Participate in meetings or assign alternate to attend - once per month until the end of 2019.
Engage in open and respectful dialogue, seeking to understand and be understood.
Communicate out to their respective organizations/communities the activities and outcomes of this TWG.
Meeting process
The TWG is anticipated to meet once per month until the end of 2019; however, this may be adjusted by the chair, if needed. The meetings will occur in Vancouver, BC. Teleconferencing and video conferencing will be used where possible to minimize travel demands. DFO will provide secretariat services to support meeting delivery and the preparation of summary meeting notes. The TWG participants will be invited to propose topics for meetings. Agendas will be approved by the chair.
Reporting
The Chair will disseminate meeting summary notes through the federal secretariat to this TWG.
Individual participants of this TWG will also report back to their respective organizations.
The Chair/Secretariat will provide draft meeting summary notes that include a record of recommendations and follow-up actions to all participants within two weeks of the meeting. The TWG will have 2 weeks to review summary notes prior to their finalization.
Budget and financial matters
Direct meeting costs (meeting rooms and videoconference/teleconference technical-related fees) will be covered by DFO.
Each participant will be responsible for their own direct costs associated with participation in the TWG meetings, including travel, accommodations and administrative support.
Appendix 3 - Summary of Sea Lice (Lepeophtheirus salmonis) management in various jurisdictions in Canada and abroad
Summary of salmon louse (Lepeophtheirus salmonis) management activities in salmon aquaculture in various jurisdictions in Canada and abroad.
Prepared By: Dr. Simon Jones
The goal of this exercise is to provide a comparative overview of strategies and tools available for the management of salmon lice in marine net pen salmon aquaculture among jurisdictions. The information was obtained from regulators, scientists and/or veterinarians in Norway, Ireland, Scotland, Newfoundland, New Brunswick and British Columbia.
The information is summarised in a table format which identifies seasonality considerations for salmon louse monitoring, management thresholds, and whether data are reported publically. The authority under which salmon louse management is implemented is identified. Also summarised are the medicinal and non-medicinal treatment and control methods currently in use in each jurisdiction. In all jurisdictions, monitoring is conducted at the farm level. When reported, data may be aggregated to provide summaries at the regional level.
There is variation among jurisdictions in the extent to which management activities (e.g., stocking, harvesting, fallowing and sea lice treatments) are co-ordinated within localised areas (e.g., Bays, Lochs, Fjords). In all jurisdictions, these coordinated area-based activities are governed by agreements between regulators and producers, or among producers, and are not mandated in legislation. The rationale for area management differs among regions. In the Bay of Fundy, Aquaculture Bay Management Areas were implemented by the Province of New Brunswick in response to outbreaks of Infectious Salmon Anemia Virus. Alternatively in British Columbia, the presence of multiple sites operated by one company in a region (e.g., Quatsino, Clayoquot, Esperanza) facilitates the coordination of management measures.
Region | Dates | Monitoring | THD | AUTH | RPT | Management | |||
---|---|---|---|---|---|---|---|---|---|
STK | HVT | FLW | TRT | ||||||
Scotland | Feb1-Jun30 Jul1-Jan31 | WK, 5x5 | 0.5af 1.0af 2.0af3 6.0af4 |
CoGP CoGP AF(S)A AF(S)A |
PUB | - | in-use | 4WK | in-use |
Ireland | Mar1-May31 Jun1-Feb28 | 2/MN, 2x30 MN, 2x30 | 0.5of 2.0of |
DAFM | PUB | in-use | in-use | 4WK | in-use |
Norway- West, -Mid | MidApr-May31 Jun1-midApr | WK, allx20 WK, allx10 |
0.2af 0.5af |
NFSA | PUB | in-use | in-use | in-use | in-use |
Norway North | MidMay-Jun30 Jul1-midMay | WK, allx20 WK, allx10 |
0.2af 0.5af |
NFSA | PUB | in-use | in-use | in-use | in-use |
CAN-NB | All year | WK | - | DAAF | PVT | - | - | in-use | - |
CAN-NL | - | - | - | FLR | PVT | - | - | in-use | - |
CAN-BC | Mar1-Jun30 Jul1-Feb28 | 2WK, 3x20 MN, 3x20 | 3.0mt 3.0mt |
FA, PAR, CoL | PUB | - | - | in-use | - |
Region | In-feed | BATH | NONCHEM | BIO | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
EMB | IVM | TFB | DFB | LFN | HPX | DTM | AZM | HL | TL | FW | CF | |
Scotland | in-use | - | - | - | - | in-use | in-use | in-use | in-use | in-use | - | in-use |
Ireland | in-use | - | in-use | - | - | in-use | in-use | - | in-use | in-use | in-use | in-use |
Norway | in-use | - | in-use | in-use | - | in-use | in-use | in-use | in-use | in-use | in-use | in-use |
CAN-NB | in-use | in-use | - | - | in-use | in-use | - | in-use | in-use | in-use | - | in-use |
CAN-NL | in-use | in-use | - | - | in-use | in-use | - | in-use | in-use | in-use | in-use | in-use |
CAN-BC | in-use | - | - | - | in-use | in-use | - | - | in-use | - | in-use | - |
Appendix 4 - Comparison of PRV, HSMI, Jaundice Syndrome in various jurisdictions
Comparison tables – Actions of various international jurisdictions regarding PRV, HSMI, and Jaundice Syndrome
Country/Region | PRV “Strain” present | Diagnosis description | Threshold for action | Management action |
---|---|---|---|---|
British Columbia | PRV-1a |
There is no diagnosis simply for PRV as it is not a disease. This step would relate to the presence or absence of PRV as detected by PCR. Fisheries and Oceans Canada (DFO) has committed to a two year targeted survey to screen for Norwegian and Icelandic PRV in hatcheries. |
There is no threshold for action set specifically for PRV. There would only be an action required for disease showing clinical signs (morbidity or mortality), and PRV itself is not a disease. Note: approach under review DFO is currently assessing the risk of transferring PRVin-use fish into the marine environment from a hatchery to determine if there will be a threshold for action in the future. |
None. Not reportable or notifiable to the Canadian Food Inspection Agency (CFIA), provincial authorities, or DFO. DFO does not currently have a management action dictated, other than licence holders must report all fish health events and mortality events. PRV is not a disease, and as such, there is no action taken if it is detected at this time in absence of illness. |
East Coast of Canada New Brunswick/ Newfoundland and Labrador/ Nova Scotia |
PRV-1a |
Not a disease, so no diagnosis can be made. |
None. Note: approach under review |
None. No management action or reporting required. No regulatory movement restrictions based on solely PRV presence. Not reportable or notifiable to the CFIA, provincial authorities, or DFO. |
Washington State, USA | PRV1-a |
Not a disease, so no diagnosis can be made. To screen for PRV, the process they use is to conduct QPCR on the L1 fragment. If this comes back positive, then sequence S1 fragment for origin, which they believe can easily be determined. Washington use the terminology “North Atlantic” or “exotic” PRV-1 for strains found anywhere in Norway or Iceland and “endemic” PRV-1 for the strain found in the Pacific Northwest. |
Hatchery monitoring: There is no requirement for PRV testing in Washington for transfers within state (with one exception: one hatchery previously tested positive for North Atlantic PRV-1, and there is a plan to monitor the facility for 3-5 years to ensure this situation is resolved). There is a requirement for PRV-1 and PRV-3 testing on any fish transfers occurring into the state from other jurisdictions. When fish are required to be tested, the sample size is 150 fish.
Marine Monitoring: Washington State will not be renewing aquaculture licences for Atlantic salmon farming after 2022. At this time, there are only 2 pens left in Washington with Atlantic salmon, and these will be harvested out in the near future. Atlantic salmon farming may be replaced with other native species, such as Steelhead. If this occurs, there are plans to test for regulated pathogens and PRV-1 (which is not regulated) 1-2 times annually/farm (which has not historically occurred). |
For hatchery to marine site transfers:
For marine testing (if this occurs in the future): There will be no response if the PRV-1 endemic strain is found to be present. Response, if any, to a positive test of North Atlantic PRV-1 is unknown at this time. Dr. Kenneth Warheit, director of fish health for the Washington Department of Fish and Wildlife (WDFW) says “The WDFW’s current management associated with PRV is consistent with that white paper [entitled “Piscine Orthoreovirus (PRV) in the Pacific Northwest Appears to be of Low Risk to Wild Pacific Salmonids]” which is referenced here: https://drive.google.com/file/d/ 1OxHv7GXddmEXA7pRH4N4MGACzdZUhUL8/view Washington state will no longer be renewing aquaculture tenures after the final one expires in 2022 for the purpose of growing Atlantic salmon. |
Norway | PRV-1a and PRV-1b |
Not a disease, so no diagnosis can be made. This virus is detected on farmed salmon and associated with HSMB (as they call HSMI) and has been found in wild salmonids without inflammation of the heart. The technique to detect PRV is a PCR method. |
There is no requirement to test for PRV in hatcheries or vaccinate (no available vaccination exists). There is some screening for PRV in smaller fish. If fish test positive, the fish health service will take samples for histopathology to determine if HSMB signs are present. |
None. Not reportable to the country’s competent authority (Norwegian Food Safety Authority). It was required ~2012 but not currently. No management action or reporting required. No regulatory movement restriction based solely on PRV presence. |
Scotland | PRV-1a |
Infection with PRV-1 is associated with HSMI but in the majority of cases is not found in conjunction with HSMI. PRV-1 has been found in wild and farmed salmonids and most often not associated with disease. HSMI has not been diagnosed in wild fish. |
None. Infection with PRV-1 is not a listed disease by the World Organization for Animal Health (OIE), European Union, or Scotland. This virus is widely distributed (in wild, farmed, healthy and unhealthy salmon). |
Not reportable to the country’s competent authority (Marine Scotland). No management action or reporting required. No regulatory movement restriction based solely on PRV-1 presence. The Aquatic Animal Health (Scotland) Regulations 2009 require that transport of only healthy animals takes place. |
Chile | PRV-1a and PRV-1b |
Not a disease, so no diagnosis can be made. Considered to be fairly ubiquitous (wild and farmed salmonids) and most often not associated with disease. |
None. |
None. Not reportable to the country’s competent authority (Sernapesca). No management action required. No regulatory movement restriction based solely on PRV presence. |
Tasmania | Not found |
Not found; so not commented on in other sections. |
N/A |
N/A |
Country/Region | PRV “Strain” present | Diagnosis description | Threshold for action | Management action |
---|---|---|---|---|
British Columbia | PRV-1a | DFO uses the following definition of Heart and Skeletal Muscle Inflammation (HSMI) in farmed Atlantic salmon populations:
|
Currently not regulated by the CFIA; however, the Agency monitors for changes that would lead to a re-evaluation of the criteria to regulate in Canada. At this time, there is no action threshold set by DFO that is different than any other disease. If it caused clinical signs (morbidity or mortality), industry would follow their Health Management Plan and SOPs in order to appropriately respond. | Currently not regulated by the CFIA; however, the Agency monitors for changes that would lead to a reevaluation of the criteria to regulate in Canada. DFO does not have a unique management action required following a positive diagnosis of HSMI, which to date has not shown clinical signs or mortality in BC. Reporting to DFO would be required if HSMI resulted in a Fish Health Event or a Mortality Event. Industry must follow Fish Health Management Plan and their Standard Operating Procedures. |
East Coast of Canada New Brunswick/ Newfoundland and Labrador/ Nova Scotia |
PRV-1a | Not currently being diagnosed; but at minimum, would require clinical and histological signs, while ruling out other known diseases. | No action threshold; not reportable or notifiable to CFIA, provincial agencies, or DFO. Currently not regulated by the CFIA; however, the Agency monitors for changes that would lead to a reevaluation of the criteria to regulate in Canada. | Not reportable or notifiable to CFIA, provincial agencies, or DFO. No management action or reporting required for HSMI. |
Washington State, USA | PRV-1a | They would need to observe clinical signs, which would be followed up with histology to look for HSMI-characteristic indicators, rule out other possible causes, and test positive for PRV in order to diagnose HSMI. | The Washington Department of Fish and Wildlife (WDFW) has not historically collected independent sampling from marine sites, but intend on initiating a program in 2020 to do so; however, all Atlantic salmon will all be out of the water by that time and not re-stocked, so monitoring will be dependent on there being other finfish in the water to monitor. At this time, WDFW can require industry to report testing results (including symptoms associated with HSMI), but have never done so. Currently no action threshold and no reported cases of HSMI. | Washington Department of Fish and Wildlife statement: they have not identified a single study to support the claim that PRV from open-water pens will harm wild fish and HSMI has never been detected in our native salmon or any fish other than farmed Atlantic salmon. The WDFW focus of their future monitoring program will be on the health of fish, not HSMI (Dr. Kenneth Warheit, pers. comm), however symptoms of HSMI will be assessed if detected. |
Norway | PRV-1a and PRV-1b | HSMI is considered endemic in Norway. Disease can be detected based on suspicion in field (i.e., clinical signs such as increased mortality and morbidity following a handling or stressful event and some fish exhibiting symptoms). Histological lesions confirm diagnosis, after other diseases (CMS and PD) are ruled out. However, the fish health service does some screening on “healthy” fish because HSMB can be hard to detect only using clinical signs in the early stages. Individual fish diagnosis is made by light microscopy (histopathology). The fish health service gets between 1-10 formalin-fixed fish for examination. One fish being diagnosed with HSMB is enough to confirm a diagnosis for the farm. | No action threshold by government. Norway considers this to be a production disease (found on farms) but not proven to exist in wild salmon at this time, although this has not been fully explored. | There are no reporting requirements for HSMI. Norway considers this to be a production disease. There is no known treatment and no vaccine on the market. If the fish health service finds histological signs of HSMB in early stages (pre-clinical signs), the company may implement changes for the rest of the production cycle: such as decreased handling and moving to a special feed. Decreasing handling and other stressors can decrease the intensity of disease outbreak. |
Scotland | PRV-1a | HSMI is detected based on suspicion in field. Gross signs are: abnormal swimming behavior and anorexia 5-9 months after sea transfer, signs of circulatory disturbance, pale heart, fluid accumulation in the abdomen, yellow liver, swollen spleen, and bruising in the perivascular fat. There is often morbidity and mortality ranging from negligible to 20%. Significant histological lesions would be present before HSMI would be diagnosed, after other causes ruled out (e.g., PD and CMS). Minor histological lesions would be identified as HSMI-like and fish would be monitored to see if it develops into HSMI in the field. Number of cases with HSMI type pathology decreased in 2018. Many subclinical with very mild pathology. | Scotland considers this to be a production disease; and there are relatively few cases within the industry and the disease has not been reported in the wild. It is therefore managed by industry not the Scottish government. HSMI is not listed as a disease by the OIE or within the EU. The Scottish Government has a disease surveillance program, primarily aimed at the diagnosis of listed notifiable diseases and emerging diseases and will test samples of moribund fish. If HSMI is diagnosed, information is provided to the industry. Industry determines the action. | Not reportable. No management action or reporting requirements for HSMI. Industry driven action. The Aquatic Animal Health (Scotland) Regulations 2009 require that transport of only healthy animals takes place. |
Chile | PRV-1a and PRV-1b | HSMI is considered endemic in Chile. Disease is detected based on suspicion in field (i.e., higher than expected increased mortality and morbidity). Histological lesions and PCR positive result confirm clinical signs. | No action threshold. | Associated mortality reported weekly. No management action required for HSMI. |
Country/Region | PRV “Strain” present | Diagnosis description | Threshold for action | Management action |
---|---|---|---|---|
British Columbia | PRV-1a | Jaundice Syndrome (aka Jaundice/anemia) is diagnosed in a farmed Chinook salmon population when there is population level mortality attributable to the disease with characteristic gross and histologic lesions, and no evidence of systemic inflammatory disease. Characteristic gross pathology includes yellow discolouration in the periorbital region and ventrum. Gills and liver are very pale (indicating anemia). Characteristic histopathology includes renal tubular epithelial cell necrosis and generally some associated liver pathology. |
Not reportable or notifiable to CFIA. At this time, there is no action threshold set by DFO that is different than any other disease. If Jaundice Syndrome caused clinical signs (morbidity or mortality), industry would follow their Health Management Plan and associated Standard Operating Procedures in order to appropriately respond. |
Not reportable or notifiable to CFIA. DFO does not have a unique management action required following a positive diagnosis of Jaundice Syndrome, which to date has caused very low levels of clinical signs or mortality (< 0.05%) in BC. Reporting to DFO is required if Jaundice Syndrome results in a Fish Health Event or a Mortality Event. Industry must follow Fish Health Management Plan and their Standard Operating Procedures. |
East Coast of Canada | PRV-1a | No Pacific salmon reared |
N/A |
N/A |
Washington State, USA | PRV1-a | No Pacific salmon reared |
N/A |
N/A |
Norway | PRV-1a and PRV-1b | No Pacific salmon reared |
N/A |
N/A |
Scotland | PRV-1a | No Pacific salmon reared |
N/A |
N/A |
Chile | PRV-1a and PRV-1b | Jaundice Syndrome is considered endemic in Chile. Disease is detected based on clinical signs (i.e., jaundice). |
No action threshold. |
Associated mortality reported weekly. No management action required for Jaundice Syndrome. |
Appendix 5 - Presentation by Dr. Craig Stephen on alternate approaches to management of fish health
Applying modern concepts of health to salmon
(PDF, 1.67 MB)
Appendix 6 - Final report of the veterinary workshop
Workshop to evaluate the DFO case definitions for Heart and Skeletal Muscle Inflammation (HSMI) in farmed Atlantic salmon, and Jaundice Syndrome in farmed Chinook salmon, in British Columbia
Dr. Ian Gardner
January 28-29, 2020.
Vancouver, British Columbia
Introduction
This Workshop was organized to fulfill a recommendation arising from the Fish Health Technical Working Group (FH TWG), established by the Minister of Fisheries and Oceans in August 2019, which suggested the convening of a group of qualified veterinarians and veterinary pathologists to examine the Department of Fisheries and Oceans’ (DFO) current case definitions for Heart and Skeletal Muscle Inflammation (HSMI) and Jaundice Syndrome in British Columbia (BC). The objective of this workshop was to review and, if necessary, revise the DFO case definitions for HSMI and Jaundice Syndrome in BC to meet the goals of monitoring these diseases and compare them to any existing international standards or conventions. This workshop sought input from practicing aquatic veterinarians, regulatory veterinarians, and veterinary pathologists from Canada, Norway, and the United States.
The workshop was held over a two-day period in Vancouver, BC at the Pinnacle Harbourfront Hotel. The veterinary facilitator and participants were invited based on suggestions by the members of the FH TWG, with the participants invited from countries with experience of the conditions in question. Additionally, the facilitator was selected by majority vote of the FH TWG from a pool of potential candidates put forward by the FH TWG. Each day was dedicated to one of the two conditions. Both days of the workshop were structured in a similar fashion - material was presented relevant to each condition, and discussions within the group followed. Discussions took the form of small “break out” groups as well as whole-group conversations. Several scientific publications were referenced throughout these conversations. For reference, these citations are listed at the end of this report.
At various points during the workshop, members were invited to vote on different issues, including on the drafted case definitions. Votes were recorded as “yay”, “nay”, or “abstain”. The Workshop facilitator and one international participant abstained from all voting. In cases where there were differing points of view preventing unanimity, the dissenting view(s) were documented.
HSMI
Introduction/context
Context on the BC experience with HSMI and idiopathic cardiopathy was provided through four presentations. These presentations gave a history and overview of the DFO Fish Health Audit and Intelligence Program (FHAIP), a summary of audit data collected from 2002 to present, a review of histopathologic analysis and common pitfalls, and independent research conducted on marine Atlantic salmon farms in BC. Audit data have shown that in the last ten years, diagnoses of idiopathic cardiopathy have remained stable, with approximately 2% of fresh silvers sampled for audit demonstrating histologic lesions. Dissent arose on whether at least some of those cases could be HSMI (i.e., not idiopathic cardiopathy) and whether the DFO FHAIP data represent the situation in BC or were affected by biases in the selection of the data presented and collection methods; the concern being that this might result in underestimation of fish-level prevalence of HSMI. On the other hand, there has been only a single longitudinal study of piscine orthoreovirus (PRV) and HSMI, and the population dynamics of PRV and HSMI at the selected farm may be unrepresentative of the true situation in BC. Questions and comments from participants were allowed during and after each presentation, and often generated short discussion. The greatest point of contention was whether there was sufficient evidence to unequivocally say that HSMI was present in BC (see Section 2b). The presenters and titles of their respective presentations are included in Appendix 4.
The case definition for HSMI used by DFO for the FHAIP at present is:
Heart and Skeletal Muscle Inflammation (HSMI) is diagnosed in a farmed Atlantic salmon population when there is population level mortality attributable to the disease and/or clinical signs (e.g., lethargy, abnormal swimming, anorexia) and;
- Characteristic microscopic lesions consistent with the disease (heart inflammation in-use/- skeletal muscle inflammation without systemic inflammation) as determined by a histopathologist are present and;
- PRV infection is confirmed, and other viral causes (i.e., salmon alphavirus (SAV), piscine myocarditis virus (PMCV) have been ruled out.
It was noted that in the DFO FHAIP, when there are two or more fish diagnosed on histology with idiopathic cardiopathy, but with no evidence of population level effects (i.e., clinical signs or mortality), idiopathic cardiopathy is recorded as a Condition of Note in the public report of the FHAIP. Therefore any subclinical instances of heart inflammation are being captured and documented by the FHAIP.
Context on the global experience with HSMI and idiopathic cardiopathy in Norway, Chile, Washington State (USA), and Atlantic Canada was provided through four presentations from participants. Presentations included case definitions (if present) and other material relevant to HSMI in their jurisdictions. Questions and comments from participants were allowed during and after each presentation, and often generated short discussion. The presenters and titles of their respective presentations are included in Appendix 4.
In Norway, HSMI is diagnosed by identification of characteristic histologic lesions in the heart and skeletal muscle. There is no requirement for clinical signs, increased mortality, or positive test results for PRV. However, a farm is unlikely to submit a healthy fish for diagnostics. Fish are submitted for analysis by industry when prompted by presentation of clinical signs or increased mortality; the histopathologist may not receive the signalment. There is no regulatory program with routine sampling of farmed Atlantic salmon in Norway. It was explained that since Norway has identified and characterized the disease (including prevalence and pathogenesis) over a 20-year period, only histology is required to make a diagnosis. The only other diseases known to cause similar lesions that are present in Norway are pancreas disease (PD) and cardiomyopathy syndrome (CMS,) both of which can be distinguished histologically and through testing for their respective viral etiologies (SAV, PMCV). In Norway, subclinical disease has been characterized as the presence of histologic lesions without clinical signs (including gross pathology) or increased mortality.
In Chile, the case definition for HSMI in Atlantic salmon is as followsFootnote 15: “suspected case: presence of characteristic clinical signs, positive result to PRV RT-PCR, or detection of characteristic lesions through histology,” and “confirmed case: positive result to PRV RT-PCR, associated with detection of characteristic lesions, through histology with or without clinical signs.” “Differential diagnosis with other diseases that affect the heart must be conducted. Main morphological changes include myocarditis, myocardial degeneration, myositis, and degeneration of red muscle. On occasion it is possible to observe multifocal hepatocyte necrosis.” Another participant reported that in Chile the diagnosis of HSMI is solely based on the presence of histological lesions and PRV, with or without clinical signs. In Chile, surveillance of all disease is conducted passively by industry using private laboratories (authorized by Sernapesca). The laboratories report to the federal authority on an annual basis. From laboratory reports, the federal authority sets disease reporting and surveillance structures for the diseases that are present in the country in three levels- exotic, endemic, and emerging. Twenty percent of all farmed Atlantic salmon mortalities reported in Chile are due to infectious-related causes, and of that number, four percent are attributed to HSMI. This disease is not regulated by Chile.
Neither Washington State (USA) nor Atlantic Canada have case definitions or experience with HSMI within their jurisdictions. HSMI has not been diagnosed in those regions.
There is currently no international standard for diagnosis of HSMI. The World Organisation for Animal Health (OIE) is the standard-setting organization and the only international body that sets case definitions for listed animal diseases. There is currently no case definition for HSMI as set out by the OIE as it is not an OIE-listed disease. The Canadian Food Inspection Agency (CFIA) currently does not regulate PRV. The CFIA does consider PRV and HSMI to be potential emerging diseases and continues to monitor the science.
In 2012, the International Council for the Exploration of the Sea (ICES) published information on HSMI in a bulletin, which has been used internationally. This information can serve as scientific advice to countries that support ICES, however it is not an internationally recognized case definition by competent authorities.
Discussion
Discussion on this topic took place in both a large group setting, with all participants around the same table, and in three small “breakout” groups which then reconvened for larger group discussion. There was significant discussion around the existing science on HSMI in BC, with several different perspectives voiced throughout. One participant indicated that there was a conclusively established causal agent (PRV) for HSMI (or at least a very strong statistical and spatial association with PRV) worldwide. The majority of participants believed that evidence for occurrence of Norwegian form of HSMI in BC as reported was equivocal or non-existent, and laboratory challenge studies had failed to produce clinical disease or microscopic lesions consistent with HSMI (as in Norway). One participant noted that, to date, no lab challenge worldwide has ever been able to reproduce the clinical manifestation of HSMI. The PRV used in challenge trials in BC is considered to be of low virulence.
The majority of participants agreed that a fish-level diagnosis was not required at this time, due to both the uncertainty of the presence of HSMI in BC and the infectious component of the disease which suggests that more than one fish would be affected in an audit sample. For these reasons, prevalence and incidence are unable to be determined currently.
The majority of participants did not believe that there was enough evidence to determine the presence of HSMI in BC waters, as evidenced through a vote.
Participants were invited to vote on “Do we have sufficient evidence to demonstrate that there is population-level HSMI in BC?” The results of the vote were as follows:
Yay: 2
Nay: 14
Abstain: 2
Reason for Yays
2 – based on the Di Cicco et al. (2017) paper, HSMI was evident in dead fish and in live (apparently healthy) fish based on longitudinal sampling in a single farm in BC
Reason for Nays-
14- not enough evidence (at present) to confirm presence of disease in BC; field-based data have not shown same clinical presentation of HSMI as in Norway, and transmission trials with Canadian isolate of PRV have failed to produce significant lesions in challenged fish.
Following this vote, and in order to continue the discussion for the DFO case definition of HSMI, participants agreed that discussion of the HSMI case reported by Di Cicco et al. (2017) was unnecessary to be able to proceed to consideration of the case definition for future cases.
In the breakout groups, participants were tasked with reviewing and, if necessary, revising the existing DFO case definitions for HSMI in BC. Each group came up with suggestions, which were all very similar to each other. It was agreed to proceed with the suggestion to format the case definition as a flowchart. The following was developed:
DFO Audit Program: Farm-level diagnosis pathway for HSMI in the marine environment
If the following five (5) situations are true:
Clinical signs (lethargy, anorexia, abnormal swimming) consistent with disease and/or farm level mortality above baseline attributable to disease;
and
Gross pathology consistent with circulatory disturbance defined as at least one of: pale heart, congested liver (and sometimes with a thin gelatinous membrane), ascites (serosanguinous), empty gastrointestinal tract, swollen spleen;
and If suspicious of HSMI then DFO will request expedited histology
Microscopic lesions include moderate to severe inflammation in the heart- epicarditis and endocarditis in the compact layer and spongey layer with myocardial degeneration and lymphocytic histiocytic infiltration in-use/- red skeletal muscle lesions with no systemic inflammation in two or more fish;
and
Confirm PRV infection in affected fish;
and
Rule out other causes of similar lesions;
then
Targeted audit performed - where 15 fresh dead and 15 live fish will be sampled and submitted for expedited histopathology of all standard organs. If histopathology shows moderate to severe inflammation in the heart consistent with HSMI in-use/- red skeletal muscle lesions with no signs of systemic inflammation in > 50% fish submitted (expedited assessment to for HSMI);
then
Perform qPCR to confirm PRV, and sequence 5 fish with lowest Ct values. This leads to a:
Provisional (presumptive) HSMI diagnosis. This would lead to:
Ongoing field investigation and Laboratory challenge trial
where
If clinical signs and/or population level mortality attributable to disease are found to persist AND if lesions are reproduced in the lab
then
Farm-level HSMI diagnosis confirmed.
If not, then new disease characterization to occur.
Participants were invited to vote for the suggested case definition flowchart up to the “provisional2 diagnosis” line. The results of the vote were as follows:
Yay: 14
Nay: 2
Abstain: 2
Reason for Nays-
The two “nays” both agreed that the overall pathway was adequate. The dissent was:
- That the end of this initial pathway should terminate in a “differential diagnosis”, not a “provisionalFootnote 16 diagnosis”; and
- That there should be no need for inclusion of clinical signs or mortality as these are more stringent criteria and reduce the sensitivity of case detection. The requirement for increased mortality above baseline is a subjective evaluation. Ruling out of other viruses was considered unnecessary and expensive given that they are not in BC and there was no indication for testing for environmental factors or other diseases
In an effort to achieve consensus, further discussion took place based on the results of the vote. The majority of participants were adamant that clinical signs and increased mortality were critical for a population-level diagnosis, so this condition remained in the flow chart. Since most of the participants agreed with the pathway, a second vote was conducted.
Participants were invited to vote to review the pathway and not the nomenclature for the result (i.e., provisional vs diagnosis). The results of the vote were as follows:
Yay: 15
Nay: 1
Abstain: 2
Reason for Nays-
- does not agree with inclusion of clinical signs or mortality (as per previous vote)
Following this vote, significant discussion and debate ensued to discuss confirmatory testing. There were many different perspectives in this discussion- several participants felt that controlled transmission tests performed in a laboratory setting were critical, while several others disagreed since the disease could be demonstrated in the field and that was sufficient. Others held different views about which molecular tests should be performed and with which tissues.
Ultimately, participants were invited to vote to accept the pathway leading from the “provisional2 diagnosis” to the “confirmed diagnosis”, specifically regarding the inclusion of positive field and laboratory studies. The results of the vote were as follows:
Yay: 12
Nay: 4
Abstain: 2
Reason for Nays-
- Two said lab challenge studies have been inconclusive so should be in-use/- (i.e., “and/or” instead of “and”)
- One said for a disease that occurs in the field, data from the field are sufficient; lab challenge is not required
- One said despite these steps, the participant does not believe diagnosis is possible with the information presently available; there is a need further research to characterise the disease in much more detail
Conclusions and recommendations
This topic generated significant discussion and debate about the existing science on HSMI in BC. In some cases, unanimity was not achieved. There were significant areas of undisputed agreement as well, for example on the need for further research into risk factors for clinical expression of HSMI disease. Three risk factors (mechanical handling of fish, concurrent disease, and environmental conditions) have been identified in Norwegian studies. The participants recommend that further research be conducted into HSMI and its potential presentation in BC, with a focus on pathogenesis and variation in virulence from other well-documented occurrences in Norway.
The majority of the participants voted on a revised case definition for HSMI in BC. The majority of participants recommend this case definition be adopted in the DFO FHAIP. Any future presumptive case of HSMI diagnosed in BC by the FHAIP (as outlined in the flowchart) would trigger confirmatory testing/monitoring in order to be recorded and reported as a “confirmed HSMI case” using the processes outlined in the flowchart. If HSMI is then confirmed, these confirmatory tests/monitoring would not be required for subsequent HSMI diagnoses.
If HSMI is not confirmed with follow-up testing/monitoring, then it was suggested that a formalized disease characterization (including unique naming), would be required. The inclusion of a targeted audit of fifteen dead and fifteen live fish for histopathology, qPCR and sequencing should enhance early detection of HSMI. If the detected PRV strain is exotic to BC, the CFIA will launch an investigation with DFO to confirm the presence of the disease, describe the current epidemiology, determine the origin, and report to the OIE.
Jaundice Syndrome
Introduction/context
Context on the BC experience with Jaundice Syndrome was provided through three presentations. These presentations gave a summary of audit data collected over a 20-year timeframe, and independent research conducted on Pacific salmon in BC. Questions and comments from participants were allowed after each presentation, and often generated short discussion. It was noted that the incidence of jaundice in farmed Chinook salmon has remained stable over time (at approximately 0.3% of all stocked fish over the audit period), with a demonstration of a seasonal pattern of occurrence and a suggested correlation between time of smolt entry into the marine environment. It has also been proposed that there is a causal link between PRV and jaundice in Chinook salmon (Di Cicco 2018). The presenters and titles of their respective presentations are included in Appendix 4.
The case definition for Jaundice Syndrome currently in use by the DFO for the FHAIP is:
Jaundice Syndrome is diagnosed in a farmed Chinook salmon population when there is population level mortality attributable to the disease with characteristic gross and histologic lesions, and no evidence of systemic inflammatory disease.
- Characteristic gross pathology includes yellow discolouration in the periorbital region and ventrum. Gills and liver are very pale (indicating anemia).
- Characteristic histopathology includes renal tubular epithelial cell necrosis and generally some associated liver pathology.
Context on the global experience with Jaundice syndrome was provided through presentations on the Chilean experience. Questions and comments from participants were allowed following the presentations, and they generated minimal discussion.
In Chile, a similar disease is called Coho salmon Jaundice syndrome (SISC) and is defined as “suspected case: presence of characteristic clinical signs in a population of susceptible fish” and “confirmed case: presence of characteristic clinical signs and associated mortality with or without lab confirmation” where “characteristic clinical signs” are yellow discolouration. In Chile in 2018, ten percent of all mortalities in Coho salmon were attributable to infectious disease. Of that ten percent, approximately half of the mortalities were classified as jaundice. SISC is not regulated by Chile.
Discussion
Following the presentations, there was significant discussion about the name of the disease in question, specifically whether the case definition was to be developed for “Jaundice syndrome” or “Jaundice/anemia syndrome”. All participants agreed that there are multiple causes of jaundice in fish, that there are multiple causes of anemia in fish, and that simply having one or both present does not infer correlation. Most participants felt that there was not enough evidence to confirm a causal link between PRV and the development of jaundice in Chinook salmon. It was also noted by several participants that the term “anemia” has historically been used incorrectly when classifying carcasses that display pallor in gills and internal tissues, which may be misleading for data analysis. Research conducted independently on FHAIP data relied on terminology used, which included “anemia”. The participants agreed that anemia cannot be diagnosed on a post-mortem basis with gross pathology or histology. A packed cell volume (PCV) or hematocrit is required.
Participants were invited to vote to review a case definition for “Jaundice syndrome”. The results of the vote were as follows:
Yay: 15
Nay: 0
Abstain: 3
Reason for abstentions-
- One participant who does not care what the disease is called; and
- Two others (Facilitator and international participant, as previous)
The group was divided into three different breakout groups for discussion on the case definitions for Jaundice syndrome. Two of the three groups suggested a very similar case definition based on Jaundice syndrome being a non-specific diagnosis after ruling out other known causes of gross yellow discolouration. The third group suggested that the existing case definition (used by DFO FHAIP) was sufficient but with the addition of ruling out other differentials as well as more specific identification of histological lesions. There was disagreement within this smaller group regarding the consideration of subclinical fish. The majority of participants agreed that it would be difficult to find subclinical fish when the specific pathogenesis and associated histological lesions have not yet been described. From this discussion, the following case definitions were developed:
Fish level - jaundice syndrome is diagnosed in a Pacific salmon when a fish with gross pathology including diffuse yellow discolouration of periorbital region and/or ventrum is found during an audit and no other known causes of jaundice are detected
Farm level - jaundice syndrome is diagnosed in a farmed Pacific salmon population when fish with gross pathology including diffuse yellow discolouration of periorbital region and/or ventrum are found during an audit and no other known causes of jaundice are detected
Participants were invited to vote to review a fish-level case definition for “Jaundice syndrome”. Just prior to this vote, and subsequent votes, one participant left the Workshop due to previously scheduled travel arrangements. They did not participate in any of the votes regarding Jaundice syndrome. The results of the vote were as follows:
Yay: 14
Nay: 1
Abstain: 2
Reason for Nays-
- participant said that if yellow discolouration is the only criterion for diagnosis, then missing subclinical cases will result in under-diagnosis of the disease
Participants were then invited to vote to review a population-level case definition for “Jaundice syndrome”. The results of the vote were as follows:
Yay: 12
Nay: 3
Abstain: 2
Reason for Nays-
- One participant said that if yellow discolouration is the only criterion for diagnosis, then missing subclinical cases will result in under-diagnosis of the disease
- Two participants said that mortality levels are important in farm-level diagnosis. Suggestion to include “mortality above baseline attributable to yellow discolouration”
It was noted that in the DFO FHAIP, when there is not sufficient information for the DFO regulatory veterinarian to definitively diagnose a cause of death at the farm-level, but there are two or more fish affected, then it is listed as a “Condition of Note”. The subsequent conversation resulted in the following revised case definitions:
Fish level - jaundice syndrome is diagnosed in a Pacific salmon when a fish with gross pathology including diffuse yellow discolouration of periorbital region and/or ventrum is found during an audit and no other known causes of jaundice are detected
Condition of note: jaundice syndrome is diagnosed in a farmed Pacific salmon population when two or more fish with gross pathology including diffuse yellow discolouration of periorbital region and/or ventrum are found during an audit and no other known causes of jaundice are detected
Farm level - jaundice syndrome is diagnosed in a farmed Pacific salmon population when fish with gross pathology including diffuse yellow discolouration of periorbital region and/or ventrum are found during an audit and no other known causes of jaundice are detected and there is population level mortality attributable to the condition.
Participants were invited to vote on the revised wording to case definitions for “Jaundice syndrome” to include “Condition of Note” and inclusion of mortality elevation at the farm-level. The results of the vote were as follows:
Yay: 14
Nay: 1
Abstain: 2
Reason for Nays -
1- participant said that if yellow discolouration is the only criteria for diagnosis, then subclinical cases will be missed and result in underdiagnosis of disease
Conclusion and recommendations
The largest source of discussion for this disease condition was the lack of science around causes of jaundice in Pacific salmon. There have been a few publications which have described specific aspects of jaundice, however there is a significant knowledge void surrounding pathogenesis of jaundice in Pacific salmon for both viral and non-viral etiologies.
The majority of the participants voted for revised case definitions for Jaundice syndrome in BC, which was a non-specific diagnosis of exclusion. The majority of participants recommend these case definitions be adopted in the DFO FHAIP. They recommend that further research be conducted into jaundice and its potential etiologies, with a focus on pathogenesis of both viral and non-viral causes. Earlier detection of new cases should be enhanced by recording jaundice as a “Condition of note”.
Concluding remarks
The majority of the workshop participants voted in favor of a revised population-level case definition for HSMI with criteria defined for a presumptive and a confirmed diagnosis. The revised definition was deemed to be more stringent (specific) and demanding than the existing case definition by some participants and lacked clarity as to diagnostic methods to “rule out” other known viral myopathies (currently absent from BC). Because of limited time, the diagnostic methods for the rule-out of other diseases were not discussed.
A fish-level case definition was not considered relevant for HSMI because the disease is considered to have an infectious component and there would likely be at least two fish detected by audit testing. Confirmation is facilitated by use of a targeted audit of fifteen live and fifteen dead fish with expedited testing. During discussions, DFO personnel indicated that targeted audits could also occur at the discretion of DFO, if only a single HSMI-suspect fish (rather than two) was detected.
Similarly, the majority of the workshop participants voted in favor of a revised population-level case definition for Jaundice syndrome, with a definition at the fish level and inclusion of a category of “Condition of note” in reporting of audit findings. The participants agreed that significantly more research into these two conditions in BC was required, and they emphasized the need for continued monitoring and surveillance. It was also recommended that the definitions drafted by the participants be adopted in the FHAIP program going forward.
At the conclusion of the Workshop, participants were invited to provide their feedback regarding the process, including:
- One participant welcomed the international perspective, but would have liked to have more international experts represented at the table.
- One participant recommended that observers be permitted at future meetings to enhance transparency of proceedings.
- One participant expressed appreciation of regulatory bodies seeking veterinary expertise on the topic of fish health.
- One participant expressed feeling apprehensive prior to the Workshop but then was pleased with the proceedings and outcomes.
- A few participants recommended better communication with the presenters regarding presentation times and distribution of materials prior to the meeting.
It should be noted that while the Workshop agenda dedicated a full day of discussion for each disease, in reality the proceedings on HSMI took up significantly more time than anticipated, resulting in a deviation from the agenda, and only a half-day discussion on Jaundice syndrome. This was likely due to the larger body of knowledge and material to cover, as well as the contentious nature of the subject. As a result, some topics like diagnostic testing were not addressed. In the future, it would be prudent to allocate more time for discussions of this nature or narrow the scope.
From my perspective as Facilitator, the workshop format which involved discussions in the larger group with smaller breakout groups (five or six participants per group) helped ensure differing opinions were able to be expressed and discussed openly before voting. I recommend that this format be used in similar workshops in the future.
References
- Dhamotharan, K., Tengs, T., Wessel, Ø., Braaen, S., Nyman, I.B., Hansen, E.F., Christiansen, D.H., Dahle, M.K., Rimstad, E. and Markussen, T., 2019. Evolution of the piscine orthoreovirus genome linked to emergence of heart and skeletal muscle inflammation in farmed Atlantic salmon (Salmo salar). Viruses, 11(5), p.465.
- Di Cicco, E., Ferguson, H.W., Schulze, A.D., Kaukinen, K.H., Li, S., Vanderstichel, R., Wessel, Ø., Rimstad, E., Gardner, I.A., Hammell, K.L. and Miller, K.M., 2017. Heart and skeletal muscle inflammation (HSMI) disease diagnosed on a British Columbia salmon farm through a longitudinal farm study. PLoS One, 12(2).
- Di Cicco, E., Ferguson, H.W., Kaukinen, K.H., Schulze, A.D., Li, S., Tabata, A., Günther, O.P., Mordecai, G., Suttle, C.A. and Miller, K.M., 2018. The same strain of Piscine orthoreovirus (PRV-1) is involved in the development of different, but related, diseases in Atlantic and Pacific Salmon in British Columbia. Facets, 3(1), pp.599-641.
- Ferguson, H.W., Di Cicco, E., Sandoval, C., MacPhee, D.D., Miller, K.M., 2019. Haemorrhagic kidney syndrome may not be a variation of infectious salmon anemia. Aquaculture, 516, 734498. https://doi.org/10.1016/j.aquaculture.
- Garver, K.A., Johnson, S.C., Polinski, M.P., Bradshaw, J.C., Marty, G.D., Snyman, H.N., Morrison, D.B. and Richard, J., 2016a. Piscine orthoreovirus from western north America is transmissible to Atlantic salmon and sockeye salmon but fails to cause heart and skeletal muscle inflammation. PLoS One, 11(1).
- Garver, K.A., Marty, G.D., Cockburn, S.N., Richard, J., Hawley, L.M., Müller, A., Thompson, R.L., Purcell, M.K. and Saksida, S., 2016b. Piscine reovirus, but not Jaundice Syndrome, was transmissible to Chinook Salmon, Oncorhynchus tshawytscha (Walbaum), Sockeye Salmon, Oncorhynchus nerka (Walbaum), and Atlantic Salmon, Salmo salar L. Journal of fish diseases, 39(2), pp.117-128.
- Kongtorp, R.T., Kjerstad, A., Taksdal, T., Guttvik, A. and Falk, K., 2004. Heart and skeletal muscle inflammation in Atlantic salmon, Salmo salar L.: a new infectious disease. Journal of Fish Diseases, 27(6), pp.351-358.
- Polinski, M.P., Marty, G.D., Snyman, H.N. et al. Piscine orthoreovirus demonstrates high infectivity but low virulence in Atlantic salmon of Pacific Canada. Sci Rep 9, 3297 (2019).
- Wessel, Ø., Braaen, S., Alarcon, M., Haatveit, H., Roos, N., Markussen, T., Tengs, T., Dahle, M.K. and Rimstad, E., 2017. Infection with purified Piscine orthoreovirus demonstrates a causal relationship with heart and skeletal muscle inflammation in Atlantic salmon. PloS one, 12(8).
Appendices
- Appendix A: Terms of Reference
- Appendix B - Agenda
- Appendix C - List of workshop participants
- Appendix D - List of presenters and presentation titles
- Appendix E - DFO FHAIP Carcass Selection SOP
- Appendix F - Executive Summary of Veterinary Workshop
Appendix A - Terms of reference
Terms of reference for a workshop to evaluate the DFO case definitions for HSMI in farmed Atlantic salmon and Jaundice Syndrome in farmed Chinook salmon in British Columbia.
December, 2019
Objective
The objective of this workshop will be to review and, if necessary, revise the case definitions for HSMI and Jaundice Syndrome in BC to meet the goals of monitoring these diseases. More specifically, we expect this workshop to include the following topics related to the current DFO case definitions (Appendix 1):
- State the goals and objectives of monitoring related to the proper management and control of fisheries and conservation and protection of wild fish.
- Discuss the need for clinically-affected fish in the case definition.
- Describe the histological lesions that are commonly associated with HSMI in Norway and other jurisdictions and describe and compare histological lesions that have occurred in BC fish.
- Discuss the significance of sub- or pre-clinical signs in disease monitoring and build consensus around possible definitions of sub-clinical signs for HSMI.
- Define the criteria for fish-level disease diagnosis.
- Define the criteria for population-level disease diagnosis.
- Review the goals and objectives and case definitions for HSMI found in the literature and used in other jurisdictions.
- Evaluate the uniqueness of the histological lesions commonly associated with Jaundice Syndrome in Chinook salmon and discuss whether they are important to be included in the case definition.
- Review and if necessary revise case definition(s) for HSMI in BC (fish and population).
- Review and if necessary revise case definition(s) for Jaundice syndrome in BC (fish and population).
- Discuss approaches to best detect disease in early stages on farms for the DFO enhanced monitoring program and recommend required testing.
Scope
This workshop will seek to review and, as appropriate, update the case definitions for HSMI and Jaundice Syndrome in British Columbia with input from practicing aquatic veterinarians, regulatory veterinarians and veterinary pathologists.
Deliverables
Specific case definitions for fish-level and farm-level diagnosis of HSMI in farmed Atlantic salmon in BC
Specific definitions for fish-level and farm-level diagnosis of Jaundice Syndrome in farmed Chinook salmon in BC
Recommended protocol for early detection of HSMI in farmed Atlantic salmon in BC in the DFO enhanced monitoring program
Recommended protocol for early detection of Jaundice syndrome in farmed Chinook salmon in BC DFO enhanced monitoring program
Recommend required lab diagnostic testing for DFO enhanced monitoring program and targeted audits
A summary report that includes the different points of view expressed at the meeting.
Roles and responsibilities
Meeting participants are expected to act in accordance with the code of conduct of their profession, contribute to the discussions and deliverables using scientific evidence and to strive for consensus (where consensus means an absence of opposition to conclusions and recommendations that are based on scientific data and information).
In cases where there is a differing point of view preventing consensus and which is supported by scientific evidence, the dissenting view(s) will be documented in the final report, including the reasons why the opinion was not supported by the majority of participants.
DFO Regulatory Veterinarians: Provide the context of existing case definitions and regulatory requirements for PRV, HSMI and Jaundice Syndrome.
CFIA Regulatory Veterinarian: Provide guidance on control of emerging aquatic animal diseases for Canada.
Salmon Aquaculture Industry Licenced Veterinarians: Provide filed level contexts for these diseases.
Other Licenced aquatic veterinarians with subject matter expertise;
Certified Veterinary Pathologists: Provide laboratory level context for these diseases.
Independent third party Facilitator: with subject matter expertise (TBA)
All participants with the exception of the Rapporteur are expected to actively contribute to the discussions and deliverables.
Rapporteur
Appendix A.1 - Case definitions currently being used by the Fish Health Audit and Intelligence Program, Aquaculture Management Division, Fisheries and Oceans Canada
Jaundice Syndrome
For the purpose of our audit farm-level diagnosis:
- Jaundice syndrome (aka Jaundice/anemia) is diagnosed in a farmed Chinook salmon population when there is population level mortality attributable to the disease with characteristic gross and histologic lesions, and no evidence of systemic inflammatory disease.
- Characteristic gross pathology includes yellow discolouration in the periorbital region and ventrum. Gills and liver are very pale (indicating anemia)
- Characteristic histopathology includes renal tubular epithelial cell necrosis and generally some associated liver pathology.
Heart and Skeletal Muscle Inflammation (HSMI)
For the purpose of audit farm-level diagnosis:
- There is population level mortality attributable to the disease and/or clinical signs
(e.g., lethargy, abnormal swimming, anorexia) and; - Characteristic microscopic lesions consistent with the disease (heart inflammation in-use/- skeletal muscle inflammation without systemic inflammation) as determined by a histopathologist are present and;
- PRV infection is confirmed, and other viral causes (i.e., SAV, CMSV) have been ruled out.
Appendix B: Agenda
Veterinarian Workshop - Review of case definitions for HSMI and Jaundice Syndrome in BC for the Fish Health Technical Working Group
January 28 to 29, 2020
9:00am – 5:00pm
Vancouver Marriott Pinnacle Downtown
1128 W Hastings St. (Room: Port of Singapore)
Time | Topic | Supporting materials |
---|---|---|
9:00 – 9:20 am |
|
- |
9:20 – 9:40 am |
|
|
9:40 – 10:30 am |
|
|
10:30 – 10:45 am | Health break | |
10:45 – 12:00 pm |
|
|
12:00 – 12:45 pm | Lunch | |
12:45 – 2:30 pm |
|
3 Breakout groups /all |
2:30 – 3:00 pm |
|
All |
3:00 – 3:20 pm | Health break | |
3:20 – 5:30 pm |
|
3 Breakout groups /all |
5:30 pm |
|
- |
Time | Topic | Supporting materials |
---|---|---|
8:30 – 8:50 am |
|
- |
8:50 – 10:oo am |
|
|
10:00 – 10:40 am |
|
3 Breakout groups/all |
10:40 – 11:00 am | Health break | |
11:00 – 12:00 am |
|
3 Breakout groups/all |
12:00 -1:00 pm | Lunch | |
1:00 – 3:00 pm |
|
All |
3:00 – 4:30 pm |
|
- |
5:00 pm |
|
- |
Appendix C - List of workshop participants
Participants – Veterinary Workshop on HSMI/Jaundice Case Definition
Facilitator: Ian Gardner - Health Management, UPEI
Rapporteurs: Laura Sitter – Field Veterinarian, DFO
Erika Anderson – Aquatic Biologist, DFO
- Emiliano DiCiccio - Fish Health Researcher, veterinarian; Pacific Salmon Foundation
- Kathleen Frisch – Fish Health Director, veterinarian; Cermaq Canada
- Brad Hicks – veterinarian, Partner (Taplow Feeds); Aboriginal Aquaculture Association
- Ian Keith – Fish Health Veterinarian; DFO Salmonid Enhancement Program
- Fred Kibenge – Pathology & Microbiology, veterinarian; UPEI
- Kim Klotins – National Veterinary Program Specialist, veterinarian; CFIA
- Gary Marty – Fish Pathologist, veterinarian; BC Ministry of Agriculture
- Hugh Mitchell – Fish Veterinarian; Fish Health Manager of Aquatactics
- Diane Morrison – veterinarian, Managing Director; Mowi Canada West
- Michael Pawlik – Veterinary Pathologist; Animal Health Centre, BC Ministry of Agriculture
- Derek Price – Veterinary Epidemiologist; DFO
- Sonja Saksida – veterinarian; Aquaculture Population Health (UPEI)
- Mark Sheppard – Fisheries veterinarian, President; Sakana Veterinary Services
- Jed Varney – Aquatic Veterinarian; Pacific Aquaculture
- Zac Waddington – Lead Veterinarian; DFO
- Patrick Whittaker - veterinarian; Grieg Seafood
- Anne Berit Olsen – veterinarian; Norwegian Veterinary Institute
Appendix D - List of presenters and presentation titles
Presenter | Presentation titles (topics) |
---|---|
Zac Waddington | DFO in the Field: Fish Health Audit and Intelligence Program (FHAIP) |
Gary Marty | History and Rationale for Diagnosis of Idiopathic Cardiopathy in BC Farm Audit Samples; Relation of BC PRV and HSMI/jaundice |
Michael Pawlik | What makes a good case definition? |
Anne Berit-Olsen | HSMI in Norway |
Derek Price | HSMI Case Definition in Chile; SISC Case Definition in Chile |
Jed Varney | PRV in Washington |
Sonja Saksida | (HSMI in Atlantic Canada) |
Emiliano Di Cicco | Analysis of the current DFO case definition for HSMI in BC and its strengths/weaknesses relative to those adopted in other jurisdictions; Analysis of the current DFO case definition for Jaundice/anemia in BC and its strengths/weaknesses relative to those adopted in other jurisdictions |
Appendix E - DFO FHAIP SOP-08 for carcass selection
Aquaculture environmental management fish health section
Section: Sampling
Title: Carcass selection
Purpose:
To establish procedures for selecting carcasses of diagnostic quality during a fish health audit. The selection process increases the likelihood for the detection of pathogens and/or disease.
References:
Biosecurity Guidelines SOP AEO FH-BIO-01 (current version)
Responsibility:
Fish Health personnel
Definitions:
Disease: A morbid process or condition of the body or its parts, having characteristic signs that distinguishes if from other morbid processes or conditions and from the normal state. Any state which results in a gradual degeneration of homeostasis.
FHAS: Fish Health Auditing and Surveillance.
Mortality Categories for facilities:
Environmental: Total number of carcasses due to environmental conditions (e.g., low D.O., algal bloom, etc.)
Non-Performers: Total number of carcasses due to non-performers (e.g., starve-out, precocious males, etc.)
Old: Total number of carcasses not of diagnostic quality (e.g., white gills and soft flesh, etc.)
Other: Any other classification facility staff may use to categorize their mortalities.
Predator: Total number of carcasses due to predation.
Silver: Total number of fresh carcasses that still have silver skin/scales having died most recently with no apparent cause of death, or these may show signs of disease. Silver carcasses are most representative of the production population.
Equipment and materials required:
- PPE
- Raingear
- Nitrile gloves
- Clean container with lid for carcass containment (provided by facility)
Safety precautions:
Always wear PPE and follow the directions of facility staff with regards to personal safety when working at a facility. This is especially important when on a sea cage system where many hazards exist – be aware of your surroundings
Policy:
All FHAS specimens, samples, sub-samples, etc. shall be handled, and contained with due care and shall not be used in such a way as to invite cross-contamination or degradation.
Instructions:
- 1.0 Carcass selection:
- 1.1 Select representative samples from all pens stocked at the facility
- 1.2 Select up to three samples for necropsy showing different external gross pathology; for example if a number of fish show yellow mouth plaques, up to three of these are selected from the site with the remainder samples consisting of other ‘silvers’ or fish showing other gross lesions. If all carcasses on a site show the same gross lesions then the all necropsy samples would consist of carcasses with these gross lesion.
- 1.3 Pens showing a higher mortality should have a higher representation in the samples collected for necropsy.
- 2.0 Carcass selection DFO present:
- 2.1 Sort through all carcasses collected during the audit (this is done with facility staff). Any moribund samples collected are to be euthanized in accordance with individual company protocols and adipose fin clipped for identification purposes. Record any moribund samples, where applicable, in the necropsy observations form.
- 2.2 Record the numbers of carcasses in each category classified by facility staff as per the previously defined mortality categories (i.e., predator, environmental, old, etc.).
The classifications recorded on the Fish Health Field Data sheet are those identified by the facility staff. If DFO does not agree with, or has any comments regarding the facility staff classifications, DFO will record this in the “Farm comments” section of the Fish Health Field Data sheet. - 2.3 Select carcasses from the “silver”, ‘environmental’ or ‘other’ category. Do not include carcasses that are ‘old’, ‘ non performers,’ “deformities,” ‘predator’ or ‘mature’ for sampling.
- 2.3.1 In cases where “poor performers,” “mature,” or “deformity” fish are noted to be significantly represented in the living or dead population, up to three carcasses will be processed and submitted for diagnostics.
- 2.4 Assess the colour of the fish’s gills. They should be bright red. However, the gills may be pale in appearance if the fish is anemic and therefore the clarity of the eyes and the bright sheen of the scales need to be taken into account for deciding sample suitability.
- 2.5 Assess the flesh firmness of the carcass. It should be resistant to indentation when pressed. It should feel firm to the touch with no evidence of autolysis.
- 2.6 Collect a suitable number of carcasses for diagnostic sampling as feasible. Be aware that there will be inherent restrictions, such as: availability of “silvers”, resources, time constraints, etc. If possible collect a maximum of 10 carcasses per facility.
- 2.7 Inform facility staff when a carcass is selected for sampling so they can make note of it for their own records.
- 2.8 Place any carcass selected for sampling into a clean, secure container.
- 2.9 Transport carcass to a covered location at the facility for sampling. (Refer to Biosecurity Guidelines SOP ...)
- 2.10 Follow all applicable SOP’s or Guidelines in SOP – Biosecurity and Disinfection Procedures during collection and transportation of samples to the necropsy area.
- 3.0 Carcass selection DFO not present:
- 3.1 If DFO is unable to be present during carcass collection, facility staff are directed to put aside all carcasses, keeping separate ‘silvers’, ‘environmental’ and ‘other’ from ‘old’, ‘non-performer’, ‘predator’, ‘mature’ for each pen.
- 3.1.1 If the amount of carcasses is large, then staff is directed to put aside a number of “silver ‘environmental’ or ‘other’ carcasses for DFO to select samples from.
Facility staff may also be requested to put aside a representative number of “non-silver” carcasses in order for DFO to examine for audit purposes (i.e., ‘non-performers, ‘mature’, ‘predator’ or ‘old’).
- 3.1.1 If the amount of carcasses is large, then staff is directed to put aside a number of “silver ‘environmental’ or ‘other’ carcasses for DFO to select samples from.
- 3.1 If DFO is unable to be present during carcass collection, facility staff are directed to put aside all carcasses, keeping separate ‘silvers’, ‘environmental’ and ‘other’ from ‘old’, ‘non-performer’, ‘predator’, ‘mature’ for each pen.
Appendix F - Executive summary of veterinary workshop
Veterinary workshop on HSMI and Jaundice Syndrome - Executive summary points
HSMI
- Presentations on HSMI: DFO audit program and BC case definitions, HSMI in Norway, Chile, Washington, Eastern Canada, and current research in BC.
- There was agreement to share presentations given at workshop as pdf files for transparency.
- Discussion on whether HSMI is present in BC. Discussion of cases reported by Di Cicco et al. 2017 and Polinski et al. 2019. These cases showed similar histopathology, but low mortality and virulence.
- Vote on whether there is enough evidence to confirm that HSMI is present in BC: Yes (2) and No (14). Reasons given were field-based data have not shown same clinical presentation of HSMI as in Norway, and failure of transmission.
- Discussion of failure of transmission trial with BC strain of PRV to cause HSMI (Garver et al. 2016). Group agreed that challenge tests are difficult, because it is hard to reproduce same stresses in lab setting.
- Agreement that HSMI is multi factorial disease. In Norway, stresses and environmental conditions influence disease expression in subclinical Atlantic salmon.
- Discussion on what is necessary to prove presence of HSMI in BC: elevated mortality, clinical signs, gross histology, complete tissue histology, PCR, and/or laboratory challenge trial?
- Fish-level case definition was not considered relevant for HSMI. If a suspect fish is confirmed, it would be a population level diagnosis due to the infectious nature of HSMI.
- Development of flow diagram of protocol for HSMI case definition (see flow diagram).
- Vote regarding agreement for population-level protocol, up to provisional HSMI: Yes (15) and No (1). No vote believes that subclinical cases without mortality are missed by this definition.
- Vote regarding confirmation of population-level diagnosis including both field studies AND challenge study: Yes (12) and No (4). Argument against included: field mortality is enough without challenge trial, challenge trials are difficult to reproduce, and too difficult/time consuming to complete both.
Jaundice Syndrome
- Presentations on Jaundice Syndrome: current BC case definition, data from DFO audit program, challenge studies, current research, including jaundice disease comparisons to Norway, Japan and Chile in Chinook, Rainbow Trout and Coho.
- Vote on terminology. Jaundice “syndrome” case definition, not jaundice “anemia” because anemia may only be measured in living fish. Vote: Yes (15) and Abstain (1). The participant abstained because they did not “care”.
- Jaundice syndrome in BC has low mortality and a predictable seasonal pattern, with mortality increasing from February to April, for summer-entry smolts.
- Jaundice syndrome is currently diagnosed by exclusion, as jaundice may be caused by other factors (e.g., Cryptobia in Washington).
- Discussion whether non-yellow Chinook with PRV and similar lesions (subclinical) may have jaundice syndrome (Di Cicco et al. 2018). Disagreement whether the lesions are specific enough to indicate disease.
- Disagreement whether there is enough evidence and understanding of the disease mechanism for PRV to be considered causal in jaundice syndrome.
- If early detection is based on yellow discoloration, early detection has limited use because death occurs hours after the jaundice fish is observed.
- Preliminary Vote on case definition without condition of note, or mortality: Yes (12), No (3) and Absent (1). Arguments against included: the need to add substantial, elevated or above baseline mortality to definition, or yellow criteria misses subclinical population.
- Final Vote on Jaundice Syndrome Case Definition including mortality in farm-level diagnosis, and condition of note before mortality is measured: Yes (14), Abstain (1) and Absent (1). Participant abstained because the participant voted no on preliminary case definition at fish-level. The participant believed the fish-level case definition misses subclinical cases in the preliminary vote.
Recommendations
- Final recommendations arising from discussions will be reviewed by participants via email before the report is released.
- Draft recommendations include:
- adoption of flow diagram for provisional and confirmed HSMI case definitions at the population level (fish level is considered irrelevant for infectious disease),
- adoption of case definition for Jaundice Syndrome including fish-level, condition of note, and population-level descriptions,
- the note that these case definitions were designed for use by the DFO audit program,
- adequate monitoring for early detection of disease by the DFO audit program,
- and adequate research on challenge trials in HSMI and etiology in Jaundice Syndrome.
- Disagreement on whether it was necessary to have a closed workshop, or allow observers during this workshop.
References
- Di Cicco E, Ferguson HW, Schulze AD, Kaukinen KH, Li S, Vanderstichel R, et al. (2017) Heart and skeletal muscle inflammation (HSMI) disease diagnosed on a British Columbia salmon farm through a longitudinal farm study. PLoS ONE 12(2): e0171471. doi:10.1371/journal.pone.0171471
- Di Cicco E, Ferguson HW, Kaukinen KH, Schulze AD, Li S, Tabata A, Günther OP, Mordecai G, Suttle CA, and Miller KM. 2018. The same strain of Piscine orthoreovirus (PRV-1) is involved in the development of different, but related, diseases in Atlantic and Pacific Salmon in British Columbia. FACETS 3: 599–641. doi:10.1139/facets-2018-0008Garver 2016
- Garver KA, Johnson SC, Polinski MP, Bradshaw JC, Marty GD, Snyman HN, et al. (2016) Piscine Orthoreovirus from Western North America Is Transmissible to Atlantic Salmon and Sockeye Salmon but Fails to Cause Heart and Skeletal Muscle Inflammation. PLoS ONE 11(1): e0146229.doi:10.1371/journal.pone.0146229
- Polinski, MP, Marty, GD, Snyman, HN, and Garver, KA. 2019. Piscine orthoreovirus demonstrates high infectivity but low virulence in Atlantic salmon of Pacific Canada. Sci Rep 9 (3297): 1-22. doi.org/10.1038/s41598-019-40025-7.
Appendix 7 - Supplemental materials
Readers are invited to visit the drop box site that has additional material related the FHTWG discussions including meeting agendas, meeting meetings, meeting materials including background documents submitted by DFO and CFIA representatives, and selected publications provided by members.
The drop box site can be found at: https://www.dropbox.com/sh/cw8reoq5u23m9rf/AAD_S8uiHgIgH8cLSQl30r6Ha?dl=0
- Date modified: