Days 1 to 5
There’s only enough brain activity to root and scoot; handling and petting puppies this early does no good, because they’re not aware they’re being cuddled.
Weeks 1 to 2
They spend 90 percent of their time sleeping. They’re susceptible to extreme heat or cold. They crawl, nurse, and seek the warmth of littermates and mother.
Weeks 2 to 3
Eyes open. Teeth begin to emerge. Puppies begin to lap liquids and take their first steps.
Weeks 1 to 3
The brain is growing very fast, and puppies are subject to brain damage if they’re dropped or injured. Handle with extreme care.
Weeks 3 to 4
Puppies hear and see, and their sense of smell becomes more complex. They begin to eat food, bark, wag their tail, and nip other pups.
Weeks 4 to 5
They’re steady on their legs, but tire easily. They paw, bare their teeth, growl, chase, play. It’s still too early to remove them from their mother or litter, and they must still be handled with care.
Weeks 5 to 7
Weaning begins. Puppies are curious, with little fear. They are learning about dominance order, can respond to human voices, and recognize people.
“The 49th Day”
The pups look away from their litter and mother and out to the world. Many people feel this is the best time for temperament testing and separating the dog from the litter.
Weeks 7 to 9
Time to renew caution: A lot of fear imprinting takes place in these weeks, so avoid exposure to anything loud, scary, or unnerving—especially bullying by other dogs or rough play with humans.
Weeks 8 to 12
Puppies need a new mother image for security. They can establish bonds with humans and accept gentle discipline, as well as learn simple command behaviors like come, sit, down, stay, and no. Socialization with humans and other animals is important, but it should be closely supervised. Exposure to loud noises should be gradual. Food rewards are effective.
Week 12
A puppy’s bladder now has the capacity to hold urine, so housebreaking should be reliable. It’s essential at this point to establish consistent patterns of housebreaking tied to proper eating and sleeping patterns.
Weeks 12 to 16
The puppy’s mental capacity is fully developed; it only needs experience. It will try to be dominant. It’s capable of undergoing formal obedience training. Praise is the most effective training tool. Puppies at this age need love, attention, discipline, socialization, and security.
Months 6 to 9
They’re not puppies anymore. This time is akin to the elementary-school years, and it’s a great time for comprehensive training.
Months 13 to 19
This is a dog’s adolescence. You may see a little rebellion. Return to the basics you know you can get from them—like a simple “sit”—to de-escalate any challenges.
Years 5 to 9
Dogs have learned enough, through life experiences alone, to be professors—but like anyone else, they can still learn and be repatterned.
Years 9-plus
These are important years to enjoy and respect. Understand how change can affect a senior dog; he or she needs your patience as much as a puppy does, but in a new way. Vision, hearing, and physical limitations can be responsible for changes in a senior dog’s behavior.
This timeline is based on research that dog trainer Marilyn Pona has used to create reliable guidelines for her work.
