Puppy Development Week by Week — The Breeder's Edition

The first 8 weeks of a puppy's life are a period of extraordinary transformation. A puppy goes from a blind, deaf, crawling neonate to a fully mobile, socially aware young dog ready for a new home — all in just 56 days.

This guide covers every week from the breeder's perspective. Each section includes what's happening physically and behaviorally, what weight changes to expect, and what you should be doing that week to give your puppies the best start.

Milestone checklist by week

Use this table as a quick-reference checklist. Each row covers the physical and behavioral changes you should see and what you should be doing as a breeder.

Week 0–1: The critical neonatal period

Newborn puppies are entirely dependent on their dam. They cannot see, hear, or regulate their own body temperature. Their world is warmth, milk, and sleep. A healthy newborn spends roughly 90% of its time sleeping and the remaining 10% nursing.

The single most important action this week is ensuring every puppy receives colostrum — the first milk rich in maternal antibodies. Puppies that miss colostrum in the first 12–24 hours are significantly more vulnerable to infection.

What you should be doing

• Weigh every puppy daily at the same time each day. Record in the Weight Tracker
• Maintain ambient temperature at 85–90°F (29–32°C) in the whelping area
• Monitor nursing — ensure each puppy is latching and getting adequate milk
• Watch the dam — check for mastitis, adequate milk supply, proper maternal behavior
• Keep the whelping area clean and dry

Week 1–2: Steady growth continues

The second week is a continuation of the neonatal period. Puppies remain blind and deaf, but their sense of smell is developing and they're becoming more coordinated in their crawling. The key metric this week is weight — puppies should be gaining 5–10% of their body weight daily.

By the end of week 2, most puppies will have doubled their birth weight. This is a critical milestone. A puppy that hasn't doubled birth weight by day 10 needs closer monitoring and possibly supplemental feeding.

What you should be doing

• Continue daily weighing — look for consistent upward trends, not single data points
• First nail trim — puppy nails grow fast and can scratch the dam's mammary glands
• Supplement weak nursers if needed — bottle or tube feeding with milk replacer
• Begin early neurological stimulation (ENS) if following a protocol — this starts between days 3–16

Week 2–3: The transitional period

This is one of the most exciting weeks for breeders. Puppies begin to open their eyes (usually days 10–14) and ears (days 14–18). The world is starting to exist for them beyond warmth and milk.

Eyes open gradually — starting as slits, then widening over 1–3 days. Vision is very blurry at first. The first baby teeth may begin to emerge by the end of this period, and puppies start attempting to stand on shaky legs.

What you should be doing

• Reduce ambient temperature to approximately 80°F (27°C) — puppies are developing some thermoregulation
• Continue daily weighing — most puppies should be approaching or exceeding triple birth weight
• Begin gentle handling — different textures, gentle cradling, brief separation from littermates
• Watch for eye and ear infections — discharge or swelling around newly opened eyes needs veterinary attention

Week 3–4: Socialization begins

Week 3 marks a major turning point. Puppies can now see, hear, and walk — and the world suddenly becomes much bigger and more interesting. This is when socialization truly begins, and it's also when weaning can start.

Play behavior emerges between littermates. You'll see the first tail wags, hear the first barks and growls, and watch puppies begin to interact with each other in genuinely social ways. This is the beginning of bite inhibition learning — puppies learn from their siblings that biting too hard ends play.

What you should be doing

• Introduce gruel — start the weaning process with puppy food mixed to a soupy consistency
• First deworming — pyrantel pamoate at 2–3 weeks
• Begin socialization in earnest — different surfaces (carpet, tile, grass), gentle sounds, brief handling by different people
• Set up a potty area — puppies begin to eliminate away from their sleeping area
• Continue daily weighing — growth may appear to slow slightly as puppies become more active

Week 4–5: Exploration and independence

Puppies are now running, climbing, and exploring with enthusiasm. Their coordination improves dramatically this week. They're lapping water, eating increasingly solid food, and spending more time awake and active.

Social play becomes more complex. You'll see chasing, wrestling, and play-fighting. Littermates begin establishing social dynamics. This is a critical window for environmental enrichment — the more novel, safe experiences you can provide, the more resilient these puppies will be as adults.

What you should be doing

• Expand the living space — puppies need room to play, explore, and potty away from sleep areas
• Increase food consistency — move from soupy gruel to thicker mush
• Second deworming
• Introduce novel stimuli — different textures, mild noises (TV, radio, doorbell), different surfaces to walk on
• Begin brief individual handling sessions — time away from littermates builds confidence

Week 5–6: Growing confidence

By week 5, puppies are well into the socialization window. They're eating softened food reliably, and nursing frequency decreases significantly. The dam will begin spending more time away from the puppies voluntarily.

This is the ideal time to introduce puppies to new people — different ages, appearances, and handling styles. Gentle exposure to outdoor environments (weather permitting and in safe, clean areas) broadens their experience base significantly.

What you should be doing

• Individual time away from the litter — brief sessions build independence without causing distress
• Introduce new people — friends, family members, different ages if possible
• Third deworming
• Safe outdoor exposure — grass, fresh air, natural sounds
• Begin basic startle-recovery exercises — drop a book, play thunder sounds at low volume

Week 6–7: Preparing for the world

Puppies now have nearly a full set of 28 baby teeth and are eating moistened kibble. They're genuinely independent little dogs — curious, playful, and increasingly aware of the world around them.

This is when the first veterinary exam and vaccinations typically happen (6–8 weeks). Microchipping is usually done at this appointment. If you're doing formal temperament evaluations (like the Volhard test), week 7 is the traditional time.

What you should be doing

• Schedule vet exams — first DHPP vaccination, wellness check, microchipping
• Begin crate introduction — brief, positive associations with a crate or small enclosed space
• Temperament evaluation — formal or informal assessment to guide placement decisions
• Review buyer applications — final screening and matching puppies to appropriate homes
• Begin preparing puppy packets — care guide, health records, food sample, blanket with dam scent

Week 7–8: Go-home preparation

The final week before puppies typically go to their new homes. Puppies are eating solid food (moistened kibble), are fully mobile, socially aware, and have had their first vaccines.

Be aware that a fear period can begin around week 8. During this window, puppies are especially sensitive to negative experiences. Avoid traumatic events — a bad experience during this period can have lasting behavioral effects.

What you should be doing

• Final vet check — health certificate for travel if needed
• Prepare puppy packets — include health records, feeding schedule, care guide, purchase contract, blanket with dam scent
• Final buyer communication — confirm pickup dates, share go-home instructions
• Send puppies home at 8 weeks or later, depending on your policy and breed
• Keep notes on individual puppies for buyer follow-up and your own breeding records

Weight tracking throughout

Weight is the most objective measure of puppy health, especially in the first weeks when behavioral cues are subtle. A growth chart that shows steady, consistent gain tells you more than any single observation.

Use the Weight Tracker to record daily weights for each puppy. The tool charts trends over time, making it easy to spot a puppy that's falling behind before the gap becomes dangerous. Weight tracking is most critical in weeks 0–3 but remains valuable throughout the entire 8-week period.

For detailed guidance on weight expectations by breed size, see our newborn puppy weight chart. If a puppy's weight trend concerns you, review our guide on when weight gain becomes a concern. For puppies showing signs of decline, our article on fading puppy syndrome covers warning signs and emergency response.

For more on the early socialization protocol breeders follow during weeks 3–8, see our breeder socialization guide. And when puppies are ready to transition to solid food, our step-by-step weaning guide walks you through the entire process.

Puppy development FAQs