ok, so the overall assumption is that this is dog aggressive, but there are variable demonstrations of aggression. Aggression where the dog wants to kill the object (dog, other animal,…) or if it is fear aggression, then the thyroid has nothing (probably) to do with the 'aggressing' towards the other dog. If the dog has a fear or inability to socialize with other dogs, then the growling, lunging, last resort bite,(if that variable is actually followed through or if the snapping is done and the fearful dog retreats)...all have different methodologies of rehab with the fearful dog making better decisions in the area of his/her tolerance trigger. CAT or BAT is what you want to talk over with a behaviorist or trainer with the knowledge.
