Scruff

Scruff was the dog of Jane Francis.

Jane took Scruff to all of the early experimental work that led to the creation of the robot Robbie. As such his barking was audible in those recordings. Once Robbie was made his creator, Carl Readon banned Scruff from the lab as he was very irritating. After this, Robbie escaped and went on a rampage. The Third Doctor deduced that it was because Robbie had formed an emotional attachment to Scruff and was sad. The Doctor brought Scruff to Robbie and he became friendly again, with Robbie playing fetch with him afterwards. (COMIC: Doctor Who and the Robot)