It may seem that all, what was stated above, does not apply to the miniature dogs (toy breeds), which are kept by many owners in a "condominium regime". This makes these dogs really comfortable: it is not necessary to walk them a lot, you can teach them to use the litter box like cats and do not spend much time on training.
The problems, associated with gaps in the behavioral development, are affecting not only the purebred puppies. In the recent years, many people are adopting pets from shelters and they also may face the risk of the same kind of problems - signs of gaps in the early development of the dog.
So, you need to approach very seriously to the first 5-6 months of puppy's life and give him enough opportunities to adequately use the external world for self-development. When we confine the dog, not allowing it at the right times to know the basic properties of the world, including the risk and anxiety, we seem to leave a puppy, "for the second year" in the school of life.
Poverty may come from the social environment. Despite the fact that the problem of socialization for kennels does not seem prevalent, sometimes we still have to deal with the manifestations of a kennel syndrome, even in those dogs that were brought up in the urban apartments.
It is believed that there is a special time when the dog is particularly easy to imprint the situations associated with fear, and this time is guilty of some phobias, encountered in dogs.
Violations of the right course of the dog's development may occur in different circumstances - in a large suburban kennel, and in a small city apartment. Beneficial effects, that environment has on the puppy may by limited by the impoverished conditions, which in future will cause many behavioral disorders in the adult dog, that is finding itself in a slightly different environment, getting to the new owners.
The process of behavioral programs development in the early stages of mammals's life have some certain sensitive periods - in these moments animals are most susceptible to the environmental signals. In these moments it is possible to start a certain behavioral programs, to develop the innate behaviors, to train the life skills, to imprint the desired images.
People like different dogs: some prefer dogs with a serious nature and formidable appearance, the other - with a friendly and cheerful disposition. But they all want their dog's behavior to fit the "frame" of normal. This framework is quite difficult to define, and very often we notice, that the dog's behavior is not right, when it is already formed.