top of page

The Stages of Puppy Development


Puppies have definite stages of development and windows of learning. Because of the research on rats, mice and puppies noted in the prior section we know that newborn puppies (and even intrauterine puppies) can learn. By day 21 all of the puppy's senses are intact, the last to "hook-up" is hearing. By 16 weeks of age the basic character of the dog appears to be formed.


Like humans, dogs belong to a species that matures slowly after birth: the newborn puppy is not completely developed and is incapable of surviving on its own. This implies a structured and caring parental environment (caring for the young), reflexes that orient the young puppy to its parents, and the existence of optimal, even crucial, periods in the development of the animal's nervous system. Dr. Patrick Bateson of Cambridge University (one of the giants of developmental psychobiology) in 1981 described how neonatal animals learn in phases. Various names have been proposed for these phases: sensitive period, critical moment, optimal period, vulnerable point, crucial stage, susceptible period, and so on. A sensitive period is a point in the maturing process when events are susceptible to leaving long-term effects, or a period when learning is easier and knowledge gained is stored in the long-term memory. During the sensitive period, a small number of determining experiences have major effects (or damages) on future behavior. The sensitive period is preceded and followed by periods of lower sensitivity, and the transition is gradual.

The notion of sensitive period is used in the place of critical period because the former extends over a longer period of time. Research has shown that ducklings become attached to their mother between the 13th and 16th hour of life, it takes 5 minutes of contact during the first hour after birth for a she-goat to become attached to the odor of her kid and a ewe needs contact within 4 hours after the birth of her lamb. Without this contact the mother will reject her young in the last two cases. These very short periods justify the term critical. Since puppies do not have such short periods of facilitated learning, we will use the term sensitive period. A brief summary of the phases of development and sensitive periods is listed below to help you understand how a puppy becomes an adult dog.

Prenatal Period
Puppies experience touch before birth. Behavioral studies have demonstrated that puppies whose mother's abdomen was petted before birth are more tolerant of touching than puppies whose mother's were not petted.


Neonatal Period(0-13 Days)
When puppies are born they are in an almost totally dependent state, they cannot see, they cannot see hear, cannot control their body temperature have very limited mobility. During the first two weeks of a puppy's life, he depends completely on his mother. Puppies are born with a good sense of smell, taste and touch and the ability to cry. He crawls, nurses, and makes noises but depends on his mother to stimulate his urination and defecation. He can feel warmth, cold and pain.


Transistional Period(14-20 Days)
The third week his eyes open, he cuts teeth, attempts to stand up and walk, and may try to lap water. He will begin to venture further away from the brood and begins to urinate and defecate without his mother's help.

Socialization Period(21 days to 12 weeks)
Something magical happens at the 21st day of life real learning begins. During the fourth week the puppy's hearing, sight, and sense of smell improve. He will bark, wag his tail, and nibble at food. This is the age at which he will begin to learn acceptable doggy behavior from his mother and littermates. He will learn how to behave with other dogs and how to keep his den clean. In order to later bond with humans and make a good pet, he also needs personal attention from humans. Puppies isolated during their first seven weeks may have behavior problems or trouble bonding with humans.
The fifth and sixth weeks, he will learn to walk and run quite well. He will play and growl with the other puppies.
Around six weeks, weaning begins. He will explore everything with a strong curiosity and very little sense of fear. Beginning with this age, the more things he has to explore, the more adventures he can experience and the more people he can meet, the better his socialization and the more confident he will become.
The 49th day has been found to be the best time for puppy aptitude testing (temperament testing). Most canine behaviorists agree that seven to eight weeks is the best age for adoption. At seven weeks the bonding to humans is at its greatest. This period continues to eleven to twelve weeks.
Around eight weeks, he will enter what is sometimes called the "fear" period. For the next two or three weeks, he will be more cautious and show fear of sudden or loud noises or motions. If he is frightened or overstressed during this period, the emotion is likely to affect him for a very long time or for his entire life. At this age he should be protected from frightening experiences and allowed to investigate things at his own pace. The puppy needs positive training during this time.
From nine to twelve weeks, he will be into everything, exploring and investigating. He will learn sounds and scents and your routine. He will follow you around and learn to respond to his name. This is also a good age to begin housetraining.


Ranking Period (3–6 Months)
The puppy is most influenced by "playmates," which may now include those of other species. He begins to see and use ranking (dominance and submission) within the household (the puppy's "pack"), including humans. He begins teething (and associated chewing). At four months of age, the puppy experiences another fear stage. He may be hesitant or fearful of new things. Allow him to take his time investigating things but do not encourage his fear. Make learning fun and keep all experiences positive. This is also the age when his permanent teeth will begin to replace those sharp baby teeth.


Adolescence/Juvenile Period (6–18 Months)
The puppy is most influenced by human and dog "pack" members. At seven to nine months, he goes through a second chewing phase, part of exploring territory. The puppy increases exploration of dominance, including challenging humans. He may also enter a clumsy and rebellious phase. He may behave as if he's forgotten everything he has ever learned. This is his transition from a puppy to a mature dog. The best thing you can do is to be very patient and continue with his training until the phase passes. If not spayed or neutered, the puppy experiences the beginnings of sexual behavior. (Spaying or neutering your puppy at this adolescent stage will likely increase the health benefits of the surgery and increase his lifespan.)


bottom of page