Stauffacher, M. 1992. Group housing and enrichment cages for breeding, fattening and laboratory rabbits. Animal Welfare 1, 105-125.

53% of rabbits who had been housed in small, conventional cages were unable to hop when being removed from their cages. A further 36% were able to hop only to a limited extent. However, 50% of rabbits kept in double cages were able to hop normally, and a further 30% reasonably well. These findings demonstrate that rabbits need more than the bare minimum floor space of the conventional cage. It was suggested that rabbits should have gnawing sticks, because in a semi-natural enclosure they spent about 20% of the time chewing on wood and branches. Housing pairs of non-breeding does represent a compromise between the interest of the breeder and the claims of the animals. It is also true that paired housing is economically attractive in housing laboratory animals before and during experiments.