Shaw, D. C. , Gallagher, R. H. 1984. Group or singly housed rats? In: Standards in Laboratory Animal Management. The Universities Federation for Animal Welfare 65-70. The Universities Federation for Animal Welfare, Potters Bar, UK.

From the available data it is concluded that housing rats singly affects survival. In both sexes singly housed animals showed a markedly lower survival rate than group-housed animals. This effect became apparent when the animals reached the age of about 80 weeks. No specific cause could be identified. Animals were housed in wire mesh cages and developed foot lesions during the second year of the study. The incidence of foot lesions was markedly higher in single housed animals than in group housed animals. It was suggested that the greater total floor space available for group-housed rats (1820 sq.cm) compared to single-housed rats (600 sq.cm) allowed for more activity thereby contributing to the lower incidence of foot lesions in group-housed rats.