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Guidance

Example enrichment study protocols

The example protocols below provide guidance on how to conduct an evaluation of environmental enrichment, using the approaches outlined in this web resource. General advice on adapting the protocols is available.

Consult the options for evaluation section to help you select the protocol that is most likely to meet your needs, or read examples from the literature that are available online.

Protocol A: Use of an enrichment item (mouse mezzanine with shelter)

Type: Behavioural observation

Preparation: Create ethogram and playroom

Observation: Daily flexibility; approx. 5 – 40 min per day

Protocol B: Playrooms for rats

Type: Behavioural observation

Preparation: Create ethogram and playroom

Observation: Daily flexibility; approx. 20 – 45 min per day

Protocol C: Video recording zebrafish behaviour

Type: Behavioural observation

Preparation: Create ethogram, set up and test recording equipment

Observation: Daily flexibility; approx. 20 – 45 min per day

Protocol D: preference test

Type: Preference test

Preparation: Modify cages

Observation: Daily flexibility; approx. 5 – 10 min

Options for evaluation

The following statements describe situations that you may face when planning to evaluate enrichment. For each statement, suggestions are given for how you could address the situation.

Examples of enrichment evaluations available online

Reference 

Evaluation type 

Study animals 

Evaluation of

Statistics 

[1] Windsor and Bates (2019) 

Nest scoring 

Safety observations 

Mice 

Four types of nesting material 

AVOVA 

[2] Schroeder et al. (2014) 

Preference test 

Zebrafish 

Different types of structural enrichment (sand, gravel and artificial plants) 

Kruskall-Wallis test; Wilcoxon test 

[3] Van Loo et al. (2004) 

Preference test 

Mice 

Nest boxes and nesting material 

Binomial test; t-test 

[4] Czezyk et al. (2020) 

Preference test 

Behavioural observation 

Zebrafish

Different types of structural enrichment (plastic plant, shelter, plastic lily pad) 

ANOVA 

[5] Li et al. (2019) 

Preference test 

Behavioural observation 

Piglets 

Music 

ANOVA 

[6] Tilly et al. (2010) 

Behavioural observation 

Motivation test 

Mice 

Smaller cage versus larger cage with more structural enrichment

Generalised linear model 

[7] Hanmer et al. (2010) 

Motivation test 

Rats 

Various toys and objects (e.g. polyester and fur covered blocks) 

ANOVA; t-test 

[8] Kahnau et al. (2022) Motivation test (automated and home-cage based) Mice Liquids (water, bitter, sweet)  Linear mixed-effects model

References

  1. Windsor Z and Bate ST (2019). Assessing the safety and suitability of nesting material for singly housed mice with surgically fitted head plates. Heliyon 5(7): e02097. doi:10.1016/j.heliyon.2019.e02097
  2. Schroeder P et al. (2014). What do zebrafish want? Impact of social grouping, dominance and gender on preference for enrichment. Laboratory Animals 48(4): 328-337. doi:10.1177/0023677214538239
  3. Van Loo PL et al. (2005). Assessment of the use of two commercially available environmental enrichments by laboratory mice by preference testing. Laboratory Animals 39(1): 58-67. doi:10.1258/0023677052886501
  4. Czezyk A et al. (2020). Does Providing Hiding Spaces for Zebrafish in Large Groups Reduce Aggressive Behaviour? Journal of Young Investigators 38(5). doi:10.22186/jyi.38.5.43-56
  5. Li X et al. (2019) Behavioural responses of piglets to different types of music. Animal 13(10): 2319-2326. doi:10.1017/S1751731119000260
  6. Tilly SLC et al.(2010). Middle-aged mice with enrichment-resistant stereotypic behaviour show reduced motivation for enrichment. Animal Behaviour 80(3): 363-373. doi:10.1016/j.anbehav.2010.06.008
  7. Hanmer LA et al. (2010). Using a runway paradigm to assess the relative strength of rats’ motivations for enrichment objects. Behavior research methods 42(2): 517-524. doi:10.3758/BRM.42.2.517
  8. Kahnau P et al. (2022). Determining the value of preferred goods based on consumer demand in a home-cage based test for mice. Behavior Research Methods 1-16. doi: 10.3758/s13428-022-01813-8