Abstract: A cage and cage cover combination having a cage cover having a plurality of stacking lugs on its upper surface, at least one stacking lug located in a middle region of the upper surface of the cover and at least one stacking lug located at a side region of the upper surface of the cover. The combination also includes an animal cage having a plurality of locating rings arranged in a middle region of its lower surface, where the at least one stacking lug located in the middle region of the upper surface of the cove is configured to couple with at least one locating ring of the lower surface of the animal cage and where the at least one stacking lug located at the side region of the upper surface of the cover is configured to match up to an lower edge of the bottom surface of the cage, such that when an animal cage is lowered onto the cage cover, the animal cage is securely retained on top of the cage cover.

Abstract: A removable cap assembly employs a cap with a curved side wall having an inner surface and an outer surface. A top portion extends from the curved side wall. A boss extends perpendicularly from the top portion. The boss further has a bottom and a top with a circumferential rib extending perpendicularly from the top and at least one ridge on the inside surface of the boss below the top and above the bottom. A stopper is dimensioned to seal the opening. The stopper has a hole therein configured to allow a fluid to flow therethrough. The stopper is maintained in the cap by the boss and the at least one ridge. The stopper includes a disc shaped base and a cylindrical wall portion extending from the base having at least one cavity corresponding to the location of the at least one ridge on the boss. A first groove in the base surrounding the wall portion is dimensioned to receive the bottom of the boss.

Abstract: A removable cap assembly includes a cap having a curved side wall having an inner surface and an outer surface. A top portion extends from the curved side wall, a boss extending perpendicularly from the top portion. The boss has a bottom and a top, a first circumferential rib extending perpendicularly from the top of the boss and a second circumferential rib extending perpendicularly from the bottom of the boss. The boss and rib defining an opening in the cap, the opening has a width and a height. A stopper is dimensioned to seal the opening, the stopper has a hole therein configured to allow a fluid to flow therethrough. The stopper is maintained in the cap by the boss and second circumferential rib, the stopper includes a disc shaped base. A cylindrical wall portion extends from the base, a first groove in the base surrounding the wall portion.

Abstract: A system and method for illuminating individual animal cages secured in a multiple cage rack is described. A first lighting system makes use of LEDs secured on the frame of a multiple cage rack; or attached to or disposed in each individual cage. A second lighting system utilizes fiber optic cables connected to or adjacent each individual cage or disposed within. Clear observation of all animals at will is economically provided without interference with normal cleaning and sterilizing procedures, utilizing the virtually maintenance free lighting system.