A cage-mounted valve assembly for delivering a fluid from a water source to a cage in an animal caging system for housing one or more animals, the cage-mounted valve assembly comprising: a valve body defining a distal portion of a fluid channel, the valve body having a bottom surface; an end cap defining a proximal portion of the fluid channel, wherein the end cap has a proximal end with an opening for delivery of water to the one or more animals housed in the cage and a distal end designed and constructed to be joined with the valve body to facilitate the delivery of water through the fluid channel; an interior stem displaceable between an open position and a closed position, the interior stem disposed at least in part in the fluid channel, wherein the interior stem has a distal end having a top surface and a bottom surface; and an exposed end proximate the opening of the end cap, wherein the exposed end may be displaced by the one or more animals to cause the interior stem to be displaced to the open position or the closed position; a spring element disposed in the fluid channel, wherein the spring element has a proximal end that abuts the top surface of the distal end of the interior stem and the spring element is capable of applying a biasing force to the interior stem; and a sealing member disposed in the fluid channel, wherein the sealing member is in abutment with the bottom surface of the distal end of the interior stem to prevent fluid from flowing through the opening in the end cap when the interior stem is in the closed position, wherein: the end cap includes a lower shoulder disposed within the proximal end of the end cap; and the interior stem includes a lower portion having a lower surface disposed in the fluid channel, wherein: the lower surface is designed and constructed to abut the lower shoulder of the end cap when the interior stem is in the closed position; and the lower surface is designed and constructed to provide a non-linear pathway through the fluid channel when the interior stem is in the open position to prevent jamming of the valve assembly. a valve body defining a distal portion of a fluid channel, the valve body having a bottom surface; an end cap defining a proximal portion of the fluid channel, wherein the end cap has a proximal end with an opening for delivery of water to the one or more animals housed in the cage and a distal end designed and constructed to be joined with the valve body to facilitate the delivery of water through the fluid channel; an interior stem displaceable between an open position and a closed position, the interior stem disposed at least in part in the fluid channel, wherein the interior stem has a distal end having a top surface and a bottom surface; and an exposed end proximate the opening of the end cap, wherein the exposed end may be displaced by the one or more animals to cause the interior stem to be displaced to the open position or the closed position; wherein the interior stem has a distal end having a top surface and a bottom surface; and an exposed end proximate the opening of the end cap, wherein the exposed end may be displaced by the one or more animals to cause the interior stem to be displaced to the open position or the closed position; a spring element disposed in the fluid channel, wherein the spring element has a proximal end that abuts the top surface of the distal end of the interior stem and the spring element is capable of applying a biasing force to the interior stem; and a sealing member disposed in the fluid channel, wherein the sealing member is in abutment with the bottom surface of the distal end of the interior stem to prevent fluid from flowing through the opening in the end cap when the interior stem is in the closed position, the end cap includes a lower shoulder disposed within the proximal end of the end cap; and the interior stem includes a lower portion having a lower surface disposed in the fluid channel, wherein: the lower surface is designed and constructed to abut the lower shoulder of the end cap when the interior stem is in the closed position; and the lower surface is designed and constructed to provide a non-linear pathway through the fluid channel when the interior stem is in the open position to prevent jamming of the valve assembly. the lower surface is designed and constructed to abut the lower shoulder of the end cap when the interior stem is in the closed position; and the lower surface is designed and constructed to provide a non-linear pathway through the fluid channel when the interior stem is in the open position to prevent jamming of the valve assembly.