The swivel system described has been used by ILOB-TNO for prolonged periods of continuous infusion. It allows for less restricted movement of animals. The swivel prevents the infusion tube from twisting. The swivel system is simple, safe to operate and cost-effective. Animals have greater movement, can stretch and turn around. The physical discomfort and psychological stress of restricted movement are greatly reduced. The potentially complicating/confusing effects on the measurements taken during an experiment are reduced.