The prenatal period is a recent addition to the developmental periods of puppies. It is thought that “long-term effects on behavioral development may also be produced in some mammals by events occurring in utero.” (Serpell, 1995, p. 80) Previous studies tended to overlook the existence of this period, since the puppy’s behavior could not be observed. With the development of the ultrasound machine, a puppy could be observed within the mother as early as the fourth week of gestation.
It was found that puppies would react to touch and/or pressure from the outside of the mother’s abdomen. In addition, it is theorized that since puppies have such a well-developed sense of touch at birth, the sense of touch would also be well-developed before birth. Puppies may be sensitive to touch received by the mother while still unborn. Studies have found that “when a pregnant animal is petted her litter is more docile (Denenberg and Whimbey 1963, in Fox 1978).” According to Fox (1975, in Fox 1978) this facilitates relaxation, emotional attachment, and socialization as well. Other studies have indicated that puppies that receive outside contact (petting of the mother) while in utero have a higher tolerance for touching than puppies who receive no contact at all. One could deduce that gentle petting of the mother’s abdomen could help to facilitate positive, beneficial puppy socialization with people.
During the first two weeks of a puppy’s life, also known as the neonate period, puppies can learn simple associations. (Serpell, 1995) However, early experience events are unlikely to carry over into later periods. Studies indicate that puppies in the neonate period do not seem to learn by experience. (Scott and Fuller, 1965) It is theorized that this is due to the fact that the puppy’s brain, sense, and motor organs are still undeveloped. Based on its limited capacity to sense and learn it would be difficult to affect the puppy psychologically, either in a positive or negative sense. (Scott and Fuller, 1965)
The next period of development is known as the socialization period. This is arguably the most important developmental period, beginning around 3 weeks (21 days) old, and ending around 12 weeks old. (Beaver, 1999) The biggest aspect of this period is social play. Social investigation (curiosity), playful fighting and playful sexual behavior (body contact) is very important to developing social relationships during its life. (Scott and Fuller, 1965) New behavior patterns are directly influenced by the puppy’s interaction with its mother and other puppies in the litter.
This is a time for developing social relationships, both among other puppies as well as with people. These behaviors are relatively easy for any individual who stays with the puppies during this period. However, there is a point where the puppies can develop a fear of strangers. At 3-5 weeks of age, puppies will actively approach strangers. Shortly thereafter stranger avoidance begins and slowly escalates until it peaks around 12-14 weeks of age. (Beaver, 1999) While this natural fear of strangers could serve as a way to keep a curious puppy away from predators, it can also hinder normal relationships with people.
During this period, startle reactions to sudden movement and sounds is now present. This serves to help the puppy learn to differentiate between which events are dangerous, and which events are safe or insignificant. (Scott and Fuller, 1965) During the socialization period, the development of attachment to certain locations occurs. This is displayed by an extreme disturbance in the puppy whenever a change in location occurs. This is known as “localization”. (Serpell, 1995) “Localization” often peaks in puppies between 6-7 weeks old (Scott and Fuller, 1965), and then tapers off after that time to the point where a change in location is no longer distressing to the puppy.
Dogs that are handled and petted by humans regularly during the first eight weeks of life are generally much more amenable to being trained and living in human households. Ideally, puppies should be placed in their permanent homes between about 8 and 10 weeks of age. In some places it is against the law to take puppies away from their mothers before the age of 8 weeks. Before this age, puppies are still learning tremendous amounts of socialization skills from their mother. Puppies are innately more fearful of new things during the period from 10 to 12 weeks, which makes it harder for them to adapt to a new home.
Puppies can begin learning tricks and commands as early as 8 weeks of age; the only limitations are the pup’s stamina, concentration, and physical coordination. It is much easier to live with young dogs that have already learned basic commands such as sit . Waiting until the puppy is older and has already learned undesirable habits makes the training much more challenging. (Beaver, 1999; Lindsay, 2000; Scott and Fuller 1965; Serpell 1995)