Environmental enrichment and welfare assessment in laboratory rabbits

1. Behavioural needs

Domestic rabbits retain motivations to forage, gnaw, explore, rest in concealment and interact socially. Barren housing restricts these opportunities. Hansen and Berthelsen [1] demonstrated that structural enrichment changes the behaviour of caged rabbits, but the value of any item depends on whether animals can and do use it.

2. From objects to opportunities

An enrichment programme should describe the opportunity it creates. A platform can provide lookout, exercise and usable floor area; a refuge offers control over exposure; hay supports foraging and manipulation. Pair or group housing offers social contact where animals are compatible. Baumans [2] emphasised integration with husbandry and research requirements.

3. Welfare assessment

Input measures such as dimensions or number of objects are easy to audit but cannot establish the animal’s experience. Outcome measures should include posture, locomotion, social behaviour, hiding, interaction with enrichment, abnormal repetitive behaviour, injuries, body condition, pododermatitis and clinical health.

4. Choice and control

Animals benefit when they can choose between exposed and sheltered areas or withdraw from social contact. Resources must not create competition. Verga and colleagues [3] connected housing and management with both physiology and behaviour, reinforcing the need to evaluate the complete system.

5. Scientific quality

Enrichment may change variability, but standardisation does not require impoverishment. A well-described environment improves reproducibility. ARRIVE 2.0 asks authors to report husbandry and housing details that may influence outcomes [5].

6. A practical cycle

1. Define the welfare risk.
2. Select safe resources that create a relevant opportunity.
3. Set observable success and adverse-effect criteria.
4. Record uptake across animals and time.
5. Modify the programme using observations.

EFSA’s review [4] supports combining resource- and animal-based measures rather than relying on a single housing label.

7. Conclusions

Good enrichment is dynamic, evidence-led and specific to the rabbits and procedures in front of the care team. Its success is demonstrated by animal outcomes.