Introduction and research question
Biosecurity is crucial for sustainable and safe aquaculture. Biosecurity entails a set of management measures to reduce the risk of transmission, development and spread of infectious diseases, between populations, production zones, means of transport, sites, and enterprises (Lillehaug et al. 2015). Deviations in biosecurity can be caused by limited knowledge, cost considerations, technology design, and increased professional and operational complexity (Larsen et al. 2020).
In Norwegian salmon farming, the smolt is essential. Actors within research, industry and government have urged for more knowledge about biosecurity, particularly for the smolt. A recent Norwegian study shows a great potential for infection control in the hatchery and wellboat operations, due to uncertainty associated with water quality, technical design and quality control (Larsen et al. 2020).
To improve biosecurity for the smolt, this research project will suggest measures for predictable and efficient water treatment and disinfection in RAS facilities ("recirculating aquaculture systems") and smolt transport. The main study topics are microflora, technology, and operational routines. To find adequate measures, several methods will be employed, and the current presentation will report the results of the first step, namely a document analysis.
Method
This is an analysis of documents from the quality management systems of three Norwegian fishfarm and wellboat companies. Documents relevant for biosecurity have been selected, such as risk considerations, technical parameter settings, operational procedures, deviation reports, internal audits, shift schedules, etc. This document analysis is a supplement to the project’s main methods of microorganism sampling, analysis of technology design, and interviews and operations of operational routines. The presentation may give hints to tentative results from the other approaches too.
Background and earlier research
The transfer of microorganisms and infectious agents between fish populations and between systems has been a challenge for the aquaculture industry since its commercialization in the 1960s. Disease spread has been reduced through technological, organizational and biological advances such as vaccines, disinfection systems, hygiene routines, and combat zones for PD and ISA. A basis for increased biosecurity is to identify risk factors that can introduce infectious agents to a fish population and use the risk assessments to make – and follow – biosecurity plans (Lillehaug et al. 2015).
Transport of live animals is one of the most prominent risk factors for the spread of infectious diseases (Sommerset et al. 2021), and in aquaculture, wellboats are a significant route of infection (e.g. Murray et al., 2002). Nevertheless, there is still limited knowledge about infection in and from wellboats. Studies of the external hull and internal seawater systems have found multiple places problematic for access and cleaning (Cahill &Floerl 2019). Biosecurity on wellboats shall be safeguarded through e.g. technical standards, cleaning practices, and hygienic treatment of intake and discharge water from the vessels, but this is not done sufficiently today (Larsen et al 2020). It has previously been described that wellboats operate with small margins which can lead to shortcuts (Fenstad et al. 2008).
There has been a significant development with the use of recirculating aquaculture systems (RAS), which require new practices and knowledge about biosecurity and disinfection routines at hatcheries (Lazado &Good, 2021). Different facilities have different practices for production and disinfection, resulting in different microbiota composition at plants (Dahle et al., 2020; Dahle et al., 2021; Lazado &Good, 2021). In addition, there are major differences in mortality between hatchery facilities, which suggests an opportunity for improvement, e.g. through routines and technology (Tørud et al., 2019). Interview studies at RAS facilities, among others, have shown that employees consider some operational routines to be unwavering due to the plant’s design, but that many hatcheries still can improve their biosecurity routines (Tørud and Størkersen 2021). Larsen et al. (2020) urge for more knowledge so it can be possible to establish a best practice for RAS facilities.
Results and conclusion
The aquaculture industry needs control of infectious agents and biosecurity. This document study shows how three Norwegian fishfarm and wellboat companies plan and control their procedures related to microflora, technology design and operational routines. The oral presentation will compare the companies’ parameters and routines regarding for example filters, UV, washing and disinfection eliminate bacteria and viruses in RAS and wellboats.
Literature
Cahill P, Floerl O (2019) Reactive treatment approaches for biofouling in internal seawater systems of large commercial vessels. Prepared for Australian Government Department of Agriculture and Water Resources. Cawthron Report No. 3280. 71 pp.
Dahle, S.W., Netzer, R., Haugen, T., Hageskal, G., Lewin, A., Ribicic, D. (2020). Overvåking av bakteriesamfunn i settefiskproduksjon. En studie av fem RAS-anlegg. SINTEF 00470.
Dahle, S.W., Attramadal, K.J.K., Vadstein, O., Hestdal, H.I., Bakke, I. (2021). Microbial community dynamics in a commercial RAS for production of Atlantic salmon fry (Salmo salar). Aquaculture 546, 737382.
Fenstad, J., Osmundsen, T. C., & Størkersen, K. V. (2009). Fare på merde? Behov for endret sikkerhetsarbeid ved norske oppdrettsanlegg. Trondheim, Norway: NTNU Samfunnsforskning.
Inglis G, Floerl O, Ahyong S, Cox S, Unwin M, …, Kluza D (2010) The biosecurity risk associated with biofouling on international vessels arriving in New Zealand. Report for Biosecurity New Zealand, Wellington, 186 pp.
Murray, A. G., Smith, R. J., & Stagg, R. M. (2002). Shipping and the spread of infectious salmon anemia in Scottish aquaculture. Emerging Infectious Diseases, 8(1), 1-5.
Larsen, JS, Ervik, L.C., Klakegg, B.R., Sandberg, M.G., Johansen, E. og Holmøy, R. 2020. Smittesikring og biosikkerhet i norsk lakseproduksjon. Sluttrapport – Mål og tiltak for styrket biosikkerhet. Rapport
Lazado, C. C. and Good, C. (2021) Survey finding of disinfection strategies at selected Norwegian and North American land based RAS facilities: A comparative insight. Aquaculture (Volume 532).
Lillehaug, A., Santi, N., and Østvik, A. (2015) Practical Biosecurity in Atlantic Salmon Production. Journal of Applied Aquaculture. (Volume 27, pp 249-262).
Sommerset, Bang Jensen, Bornø, Haukaas, og Brun. (2021). Fiskehelserapporten 2020. Oslo: Veterinærinstituttet 2021.
Tørud, B., Bang Jensen, B., Gåsnes, S., Grønbech, S., Gismervik, K. (2019) Dyrevelferd i settefiskproduksjonen – SMÅFISKVEL. Veterinærinstituttrapport 14-2019. Oslo: Veterinærinstituttet.
Tørud, B., og Størkersen, K.V. 2021. Arbeid med fiskevelferd på settefiskanlegg. Veterinærinstituttrapport 1-2021. Oslo: Veterinærin.