Abstract: A cage-mounted fluid delivery system for delivering a fluid from a water source, such as a fluid bag or an automatic water system, to animals housed in cages in high density caging systems may comprise a fluid delivery valve assembly, wherein the fluid delivery valve assembly is adapted to be coupled to the water source to facilitate the provision of fluid to animals housed in the cages. The cage-mounted fluid delivery valve assembly may further comprise a valve body and end cap, which may be joined together, that define a fluid channel. The cage-mounted fluid delivery valve assembly may further comprise sealing elements, a spring element, and an interior stem disposed at least in part in the fluid channel to open and close the fluid channel.