The first 12 weeks of life are extremely important and determine, to a great extent, a puppy’s personality and sociability. Studies show that puppies go through a series of developmental stages. The successful negotiation of each stage is essential to avoiding future problems such as timidity, fear-biting, phobias, and dominance aggression. A pup with little or no exposure to people and dogs during the first three months of life adjusts poorly as an adult – despite attempts to compensate for this at a later date.
Separating puppies from their mothers and littermates before 6 weeks of age has been found to have adverse effects on a puppy’s weight and physical condition. During the period between 3 and 8 weeks of age, puppies are receptive to and greatly influenced by interactions with their dam, littermates, and other dogs on the premises. These interactions enable the puppy to develop self-awareness and adopt appropriate dog behavior.
The ability to get along with dogs later in life is due, in part, to a smooth transition through this 3 to 8 week period. Thus, puppies should remain with their dam and littermates until they are 8 to 10 weeks of age and are fully weaned and eating puppy food.
Between 5 and 7 weeks of age, puppies become receptive to forming relationships with people. During this stage, puppies learn the leadership role of human beings and also learn that people are not threatening and provide food, pleasure, and rewards.
At 8 to 9 weeks, puppies develop strong preferences for urinating and defecating on certain types of surfaces – carpets, floors, grass, dirt, and so on. Housetraining can begin at this age. If the puppy room has been divided into two or more distinct areas, puppies will have started to housetrain themselves by using one area to eliminate. Providing such an area with a distinctive substrate, such as wood shavings, will help the pups adjust in their new homes. The new families can then put some wood shavings out in the area of their yard they wish the pup to eliminate on.
At 10 to 12 weeks, and again at 16 to 20 weeks, puppies are curious and do well exploring novel environments. This is a good time to begin car rides, obedience classes, and trips to the park.
In summary, it is critical that breeders expose puppies to other dogs starting at 3 weeks of age. Successful interactions are those that build confidence, are not stressful, and do not frighten the puppy. Handling puppies younger than 5 weeks of age is not detrimental, as long as it is not extremely stressful and does not induce fear. After 5 weeks, puppies should be picked up, petted, and handled in a pleasurable manner with increasing frequency.
Socialization should continue when a puppy goes to his new home. It is best to expose your puppy to as many positive experiences as possible. Take him with you in the car and go for walks where you will see other people and dogs. This allows the pup to get used to the noise and distractions of public life and meet and play with dogs who are gentle, friendly, and well socialized.
From about 12 to 14 or 16 weeks, your puppy’s immune system will be in flux. The maternal immunity he got from nursing is wearing off and his own immune system is starting to kick in. At this time, it is best to have your pup around only those other dogs whom you know are healthy and to avoid areas where large numbers of unknown dogs may gather.