Research Before Policy: Identifying Gaps in Salmonid Welfare Research That Require Further Study to Inform Evidence-Based Aquaculture Guidelines in Canada

Abstract

Aquaculture is a growing industry worldwide and Canadian finfish culture is dominated by marine salmonid farming. In part due to increasing public and stakeholder concerns around fish welfare protection, the first-ever Canadian Code of Practice for the Care and Handling of Farmed Salmonids was recently completed, following the National Farm Animal Care Council's (NFACC) rigorous Code development process. During this process, both the Scientific (responsible for reviewing existing literature and producing a peer-reviewed report that informs the Code) and Code Development (a diverse group of stakeholders including aquaculture producers, fish transporters, aquaculture veterinarians, animal welfare advocates, food retailers, government, and researchers) Committees identified research gaps in tandem, as they worked through the literature on salmonid physiology, health, husbandry, and welfare. When those lists are combined with the results of a public “top-of-mind” survey conducted by NFACC, they reveal several overlapping areas of scientific, stakeholder, and public concern where scientific evidence is currently lacking: (1) biodensity; (2) health monitoring and management, with a focus on sea lice infection prevention and management; (3) feed quality and management, particularly whether feed restriction or deprivation has consequences for welfare; (4) enclosure design, especially focused on environmental enrichment provision and lighting design; and (5) slaughter and euthanasia. For each of these five research areas, we provide a brief overview of current research on the topic and outline the specific research gaps present. The final section of this review identifies future research avenues that will help address these research gaps, including using existing paradigms developed by terrestrial animal welfare researchers, developing novel methods for assessing fish welfare, and the validation of new salmonid welfare indices. We conclude that there is no dearth of relevant research to be done in the realm of farmed salmonid welfare that can support crucial evidence-based fish welfare policy development.

A theoretical approach to improving interspecies welfare comparisons

“…Making interspecies welfare comparisons can have other implications, particularly in relation to identifying bias in discussions of animal welfare. Animal welfare concerns have primarily been directed at terrestrial vertebrates used in agriculture, laboratory research, and as companion animals (e.g., Russell & Burch, 1959;Lundmark et al, 2014;Cardoso et al, 2017;Franks et al, 2021;Gaffney and Lavery, 2022). However, many species used in intensive production systems, such as fish, shrimp, and silkworms, have received little attention and consequently, their welfare is often regarded with less concern (e.g., Elder & Fischer, 2017).…”

“…We would also like to extend our gratitude to Open Philanthropy and Rethink Priorities for facilitating and funding this work. A preprint of this article (Gaffney et al, 2022) can be found on preprints.org.…”

A Method for Improving Interspecies Welfare Comparisons

“…Making interspecies welfare comparisons can have other implications, particularly in relation to identifying acceptable standards of animal welfare. Animal welfare concerns have primarily been directed at a narrow selection of species, such as pigs and chickens (e.g., Franks et al, 2021;Gaffney & Lavery, 2022). Many species used in intensive farming systems, such as fish, shrimp, and silkworms, have received little attention and consequently, their welfare is often regarded with less concern (e.g., Elder & Fischer, 2017).…”