A rack system having shelves configured to support a plurality of disposable animal cages may include a modular configuration that is adapted to easily provide a desired rack size during manufacturing. A rack system may also include shelves which are configured to receive disposable cages and which have spring biased rails configured to receive edges of the disposable cages and provide a spring bias pushing apertures of a cage against nozzles of the shelf to provide a seal therebetween. A rack system may also include shelves which are configured to receive disposable cages and which have resilient flexible lids configured to deflect for releasable engagement into the rack assembly and establish a seal between the nozzle and receptacle for a controllable flow of air therethrough. A rack system may also include a monitoring system that includes at least one sensor in communication with a exhaust manifold of a cage that provides information to a controller that communicates cage conditions to a user via a graphic user interface. The controller may also provide information to a user independent of sensor data.
