De Villiers, C., Seal, J. V. 2010. Solid floors versus wire floor housing for rats revisited: Influence of age and the presence of test boxes. Animal Technology and Welfare 9, 31-36.

Data did not reveal a clear preference for solid floors. Juveniles were found most often on wire floors while among adults, a preference for solid floors was apparent only in females, and only when a nest box was available.