The Vetland Large Animal Anesthesia System (LAS-4000) is a complete large animal anesthesia support system. The Vetland LAS-4000 can be used for spontaneous breathing, or its operator may utilize the popular reconditioned vaporizer. The Drager AVE ventilator is an electronically-controlled, time-cycled, pneumatically-driven anesthesia ventilator capable of delivering from one half (1/2) liter to 15 liters of tidal volume at 1-to-99 breaths per minute, and I to E ratios from 1-to-2 up to optional 1-to-8. The tidal volume can be adjusted via a rocker switch that electro-mechanically adjusts the tidal volume setting.