A disposable animal cage which can be used in a ventilated or static caging rack system includes a cage top and a cage base. Any corner or edge present in the interior of the cage base or the cage top that is accessible to an animal that can be contained in the cage is defined by surfaces having a conical section which is non-circular to prevent gnawing of the cage. The cage top can include a water housing mount pocket. The water housing mount pocket can have a conical shape to prevent an animal from gnawing the water housing mount pocket and a container received in the water housing mount pocket. A feed tray can be attached beneath a filter in a ceiling of the cage top to prevent an animal from gnawing the filter.