Description and validation of a preference test system to evaluate housing conditions for laboratory mice

Housing conditions for laboratory animals can affect animal well-being and experimental results. There are guidelines for laboratory animal husbandry but these are insufficiently based on objective research and thus may not reflect the actual needs of the animals. In order to evaluate housing conditions for laboratory mice, we developed a non-invasive preference test system. The possible application of the multiple-choice housing system is as follows. Individual mice can be offered different housing conditions in different test cages. During the test period the movements of the mice between the test cages can be detected automatically. Simultaneously, behaviour of the animals can be recorded with a mouse-directed video system. When interpreted with caution, combined analyses of relative dwelling times and animal behaviour can give information on the preference of mice for the housing conditions under study. The results can advance the selection of proper housing conditions for laboratory animals. In this paper, a detailed description of our preference test system is given and its validity discussed.