Delivery system controlled administration of beneficial agent to ruminants

摘要

A dispensing device is disclosed for delivering a beneficial agent. The device comprises (1) a semipermeable housing defining an internal space, (2) a dense member in the space, (3) a heat responsive composition containing a beneficial agent in the space, (4) an expandable member in the space, and (5) a passageway in the semipermeable housing for delivering the beneficial agent from the dispensing device.