Hell yeah! Get 'em under and they'll be too out of it to realize they've become the doggie pound bitch or had been making life on a farm a little less monotonous for the animals. Maybe it implants a subconscious desire for those exact experiences they think are invasive thoughts and that they're having awful zoophilic fantasies, unaware that they are in fact memories. Then get 'em under again, watch the magic happen once more, and they'll wake up worse off than before.