Developing an early-stage welfare assessment protocol for companion rabbits.

Many welfare concerns have been reported for rabbits kept on farms and for those kept for private purposes, and there is a general lack of knowledge regarding appropriate rabbit husbandry among rabbit owners. While welfare assessment protocols have been developed for farmed rabbits, no such protocols currently exist for companion rabbits. The aim of this review was therefore to take the first step towards a welfare assessment protocol for privately owned rabbits. This was achieved by identifying feasible and valid welfare indicators for privately owned rabbits and to compile these into an adapted welfare assessment framework based on the Five Domains model. To this end, two separate searches was carried out in Web of Science in 2025, aimed at identifying and evaluating current evidence of the validity, reliability, and feasibility of non-invasive animal-based welfare indicators for rabbits kept on farms and used in research, as well as identifying behavioural-based indicators for companion rabbits and extracting evidence of their validity. From the literature search, 257 publications met the inclusion criteria, and from these, 41 welfare indicators were identified. Based on evidence of feasibility and validity, several promising welfare indicators were proposed as both relevant and suitable for the welfare assessment of companion rabbits, covering all welfare criteria required for holistic welfare assessment. Although research on rabbit welfare has historically been limited, this review identified an increase in welfare-focused studies across sectors. Even so, substantial welfare concerns remain evident among rabbits across sectors, and studies developing and testing behavioural indicators of positive welfare remain scarce, resulting in limited availability of evidence-based indicators for practical use. Moreover, given the increasing range of use contexts to which rabbits are exposed, identifying indicators capable of inferring short-term emotional responses across different situations would be valuable. Overall, this review provides a welfare framework and indicators for further development of a welfare assessment protocol for privately kept rabbits, integrating existing evidence-based indicators while identifying priorities for future research, including validation, assessment of reliability among owners, and refinement across diverse use contexts. A welfare assessment protocol aimed at rabbit owners may not only support improvement of companion rabbit welfare, but may also serve an important educational role by increasing owners' knowledge of the species-specific needs of rabbits.