It's not uncommon for a dog to take a dislike to a whole breed or type of dog for seemingly no reason.
Dogs will typically react aggressively towards other dogs for two reasons, fear, or they believe the other dog represents a threat. Your dog may perceive a threat to their status or safety, or they may even be protecting you against an apparent threat.
Aside from their heightened sense of smell, another reason why dogs may seem to dislike other dogs instantly can be from historical experience. For example, if your dog has been attacked by another dog, he might exhibit intense fear and aggression towards other dogs.
Dogs in the same household can become aggressive toward each other for a variety of different reasons. Aggression may be dominance-related, territorial, possessive, or caused by fear/anxiety. Some dogs have “alliance aggression”.
Dogs that are reactive overreact to certain stimuli or situations. Genetics, lack of socialization, insufficient training to learn self-control, a frightening experience, or a combination of these can cause reactivity, and fear is typically the driving force.
Reactive dogs become overly aroused by common stimuli. They may lunge, bark and growl, becoming so preoccupied with whatever is triggering the emotion that they can be difficult to control and move out of the situation. A reactive dog is usually a fearful dog.
❖ How dominance is established: Dogs usually establish their dominance hierarchies through a series of ritualized behaviors that include body postures and vocalizations that don't result in injury. One dog may "stand over" another by placing his paws or neck on the shoulders of the other.
Under no circumstances should the dogs be allowed to "fight it out." You could be injured due to redirected aggressive attacks, or when you attempt to break up the fight (see below).
He might be trying to tell you he is afraid of the other dog or he may be verbally staking his claim on "his territory." Most owners quickly become upset when their pup growl and quite often their first reaction is to scold or punish their dogs.
A dog might growl to threaten another dog, or it might be a response to feeling cornered. Growling is also a common symptom of resource guarding. An injured dog will often growl to keep others at bay. In these cases, and more, growling indicates something is bothering your dog.
If your dog behaves himself, reward him for his polite behavior in the presence of the other dog. Gradually work up to rewarding the dog for being close to the other dog, getting closer and closer each time. Of course, the best way to remedy this is to have your leashed dog interact frequently with other leashed dogs.
Dog selective dogs often have certain types of dogs that they are comfortable with or who they don't like. Sometimes this preference is based on the size of the other dog or on a certain physical characteristic like pricked ears.
Dogs sometimes don't like certain people, and their owners can't explain why. But scientists are increasingly learning more about dog behavior and cognition.
Your Dog Follows You
According to the pack code, alphas are at the front of the line, betas are in the middle, and omegas are in the back and double as lookouts. If your dog follows you, this indicates it sees you as the pack leader and is exhibiting the instinctive behavior of walking behind the alpha.
Most dogs assume a neutral or submissive role toward people, but some dogs will challenge their owners for dominance. A dominant dog may stare, bark, growl, snap, or even bite when you give him a command or ask him to give up a toy, treat, or resting place.
Introduction of a New Pet
Bringing home a new puppy or another adult dog can trigger jealousy in your dog, and they may show signs of aggression toward the new addition. Your dog might growl at the new dog, guard your lap, or try to get in between you and your new furry family member.
Pit Bull Terriers
Probably the most notorious breed on this list, the pit bull has a reputation for unpredictability and aggression, even against its owner or his family. State and local governments have been vigorous in restricting ownership of this dog with breed-specific legislation.
Reactive behaviors usually crop up in adolescence around 6 to 18 months of age and tend to get worse as the dog reaches social maturity around 2 or 3 years of age. Your pup will not “grow out of” this behavior. Seek help as soon as you notice an issue.
Which dog breeds are most reactive? Dogs considered highly reactive also include the Boston, Fox, Cairn and Yorkshire Terriers, Pekingnese, Weimaraner, Pug, Irish Setter, Shetland Sheepdog, Shih Tzu, Poodle, Bichon Frise, Springer Spaniel, the Westie, Chihuahua and the Dachshund.
The signs of a dominant and aggressive dog include staring; excessive low-range barking; snarling; growling and snapping; standing tall; holding ears erect; and/or carrying tail high and moving it stiffly from side to side. However, beware, often a dominant aggressive dog will give no sign before biting.
It's pretty common for us to hear from owners that their dog used to like other dogs but suddenly stopped. Often they can't put their finger on a specific reason why but with some digging we usually find it happens between 8 months and 2 years old as dogs progress through adolescence into adulthood.