Gunny is fairly well disciplined, as it is a requirement of her Service Dog Training. Which is not to say she is not tempted and were it not for my diligence, she would bolt after any prey critter in a heartbeat. As she is a Boxer, the breed was bred to run down prey and hold it until the master arrives, so it has been a very tough lesson to get her to learn, since she is 'hardwired' to do exactly that. She reacts just like the dog in the video when I say 'Squirrell', she immediately starts looking for it. I do it to desensitize her to the idea of chasing.