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Induction for Surgery. At this stage the pet (in this case an intact male dog) is given a dose of medication to place it under a plane of general anesthesia. The Medications are administered intravenously and take effect almost immediately. While they are fast-acting, their duration is short lived. As quickly as possible, the dog is intubated (a plastic tube inserted into it's trachea) to guarantee an open passageway through which the Veterinarian can deliver oxygen mixed with an anesthetic gas so that the animal will remain under general anesthesia ("asleep") during the procedure.