Housing cage for laboratory animals

A cage for housing laboratory animals, comprising:

• a cage base and a lid attachable to said cage base and having a seat for receiving in a removable manner a drinking bottle, said cage base comprising a bottom wall defining a base plane and having an inner surface on which the animals can reside, and an outer surface, wherein said bottom wall defines a raised portion protruding into an interior of said cage base and configured with a plateau portion with respect to said base plane such that the animals can reside thereon;
• wherein said outer surface of the bottom wall includes a recess conforming to and aligned with said raised portion of said bottom wall, said recess being arranged so that, when said cage is placed directly above a second like cage inside a cage post of a housing shelf, said recess is in alignment with a second seat formed on a second lid of the second cage which is inserted in the cage post below the cage, wherein said cage base has a substantially quadrangular shape comprising a pair of short sides and a pair of long sides, wherein said recess is adjacent to one of said pair of short sides of said cage base and to one of the pair of long sides of said cage base which define a corner of said cage base.