Ever wonder what's going on in your puppy's head? Research shows that puppy behavior is a lot like a human child's behavior during what's known as the juvenile period, which starts at about three months of age.
Just like teenagers, dogs in the puppy stage are testing the rules and seeing how far they can push boundaries. The juvenile period in dogs has not been well studied scientifically, but research shows that dogs are becoming more self-reliant and independent at this age. As they grow, puppies, who are born very dependent on their mother, begin learning to make their own way.
As a dog becomes more independent during this stage of puppy development, his caregiver becomes less and less the center of the universe. Instead, the environment becomes more interesting. And with greater physical ability to interact with the environment, older puppies are more easily distracted and less reliable in response to requests their Pet Parents make, such as cues they were taught early on (for example: sit, down, stay).
During this exploratory period, boundary-testing puppies are highly active, very playful and chew a lot. These activities are all normal, as young puppies make the change from puppy behavior to adult dog behavior. They have as much ability to perform complex tasks as adult dogs do, but struggle against their short attention spans.
While a puppy is feeling out the world, it's important to to play with him on a daily basis. But be careful to avoid aggressive games like tug-of-war or wrestling. He may perceive these as games of dominance - especially if he wins. You may notice your puppy naturally engages in these types of games, but you shouldn't encourage them. Aggressive play teaches your puppy that fighting with you is okay.
At this age, puppies need positive behavior training since their hormones can influence 'delinquent' behavior. When he is between four and ten months old, a male puppy's testosterone levels may be up to five times higher than an adult canine's. This is one way adult dogs distinguish that even big puppies are still juveniles and that they must be taught proper dog etiquette as part of their puppy development.
Even while your puppy acts out, you might also notice he experiences a fear-based phase. It may last up to a month, especially in large breed dogs. This fear of the world is normal and is not cause for your concern. It tends to correspond with growth spurts, and is characterized by unwarranted aggression and protective posturing of toys or territory.