Considering aspects of the 3Rs principles within experimental animal biology

Abstract

The 3Rs - Replacement, Reduction and Refinement - are embedded into the legislation and guidelines governing the ethics of animal use in experiments. Here, we consider the advantages of adopting key aspects of the 3Rs into experimental biology, represented mainly by the fields of animal behaviour, neurobiology, physiology, toxicology and biomechanics. Replacing protected animals with less sentient forms or species, cells, tissues or computer modelling approaches has been broadly successful. However, many studies investigate specific models that exhibit a particular adaptation, or a species that is a target for conservation, such that their replacement is inappropriate. Regardless of the species used, refining procedures to ensure the health and well-being of animals prior to and during experiments is crucial for the integrity of the results and legitimacy of the science. Although the concepts of health and welfare are developed for model organisms, relatively little is known regarding non-traditional species that may be more ecologically relevant. Studies should reduce the number of experimental animals by employing the minimum suitable sample size. This is often calculated using power analyses, which is associated with making statistical inferences based on the -value, yet-values often leave scientists on shaky ground. We endorse focusing on effect sizes accompanied by confidence intervals as a more appropriate means of interpreting data; in turn, sample size could be calculated based on effect size precision. Ultimately, the appropriate employment of the 3Rs principles in experimental biology empowers scientists in justifying their research, and results in higher-quality science.

Shade as enrichment: testing preferences for shelter in two model fish species

“…Several calls have been made for evidence-based identification of biologically meaningful aspects and standardisations of enrichment used across studies and species of fish (Brydges & Braithwaite, 2009;Huntingford et al, 2006;Näslund & Johnsson, 2014). This is important not only for the broad variety of fish used as model species in biomedical, physiological and behavioural research (Ashley, 2007;Browman et al, 2018;Huntingford et al, 2006;Sneddon et al, 2017;Williams et al, 2009) and may also be useful for ornamental fish in captivity worldwide ((Ploeg et al, 2007); see also Stevens et al (2017)).…”

Ethical considerations in fish research

“…However, power analyses are closely related to the P ‐value and it has been argued that interpretation of data based on P ‐values can lead to incorrect conclusions. Therefore, consideration of the effect size is also important (Sneddon et al ., ). Additionally, it is not uncommon to see comments within manuscripts where samples have been lost due to equipment malfunction; thus, a perfectly designed experiment based entirely on power analysis, may fall short if a few samples are lost through technical or human error.…”

“…UK law considers fishes in terms of use in scientific procedures to be those that are capable of independent feeding. Similarly, Canadian guidelines do not require ethical clearance for yolk‐sac dependent embryos (Sneddon et al ., , box 1 gives details on other countries). The time to independent feeding from fertilisation varies considerably depending on the species.…”

“…In zebrafish Danio rerio (Hamilton 1822), feeding starts around 4-5 days post-fertilisation but for other species such as salmonids this period may take several months. The use of fish embryos instead of later stages is therefore considered partial replacement and has been used extensively in toxicity studies with a move to use the fish embryo test (FET) as a replacement for the acute fish toxicity (AFT) test (Belanger et al, 2013;Schaeck et al, 2013;Sneddon et al, 2017). This arbitrary cut-off point in guidance and legislation should be considered from an ethical standpoint with caution.…”

Effects of repeated anaesthesia on gill and general health of Atlantic salmon, Salmo salar

“…In terms of implementing the 3Rs principles of replacement, reduction, and refinement (Russell et al, 1959), aquaculture research methodologies are currently less developed than systems used for mammalian studies (Sneddon et al, 2017). However, recent work has shown a new focus on reduction and refinement for salmonid pathogen challenges in the framework of non-destructive individual monitoring (Braceland et al, 2015;Chance et al, 2018;Collet et al, 2015;Monte et al, 2016;Urquhart et al, 2016), with the scope that the approach allows to obtain more informative and robust data from the same number of individuals or that fewer fish can be used to obtain similar quality data, (Hall et al, 2018).…”