Cage dimensions are the specified measurements of an enclosure—floor area and the linear dimensions from which it is calculated—that determine the space available to each occupant. Minimum space allowances are legislated by body weight and stocking rate on the assumption that crowding is stressful [1], although the figures derive largely from professional judgement rather than empirical welfare science [2]. Systematic variation of space allowance across conventional ranges produced no consistent effects on growth, stress physiology, emotionality, or home-cage behaviour in mice, whereas larger group size increased aggression in males of one strain [3]. Social composition can outweigh area: dominant rats make more optimistic judgements than subordinates at equal density [1]. Cage dimensions therefore define available space, not welfare [2].
- cage dimensions
- floor area
- space allowance
- stocking rate
- group size
References
- Timothy Hugh Barker; Rebecca Peta George; Gordon Stanley Howarth; Alexandra Louise Whittaker; Assessment of housing density, space allocation and social hierarchy of laboratory rats on behavioural measures of welfare. PLOS ONE 2017, 12, e0185135. [CrossRef]
- A L Whittaker; G S Howarth; D L Hickman; Effects of space allocation and housing density on measures of wellbeing in laboratory mice: a review. Lab. Anim. 2012, 46, 3-13. [CrossRef]
- Jeremy D. Bailoo; Eimear Murphy; Justin A. Varholick; Janja Novak; Rupert Palme; Hanno Würbel; Evaluation of the effects of space allowance on measures of animal welfare in laboratory mice. Sci. Rep. 2018, 8, 713. [CrossRef]