A Puppy’s First Year: The Health Timeline

The first year has more moving parts than any other. Here is the whole thing in order.

Before you collect them

• Choose responsibly. See the puppy with the mother, in the place they were raised. Ask about health testing relevant to the breed — hip and elbow scores, eye testing, DNA tests
• Register with a vet and book a check-up for the first few days
• Arrange insurance to start on day one, before anything is on the clinical record
• Ask what they have been fed, and buy the same food

8 weeks (collection)

• Vet check within 48 hours. Heart, eyes, ears, joints, palate, hernias, and — in males — whether both testicles have descended
• Microchip. Legally required by eight weeks in some countries, and the breeder is usually responsible. Transfer the registration into your name immediately
• First vaccination, often done by the breeder
• Worming, typically every two weeks until twelve weeks
• Start socialisation immediately, carrying the puppy outside before the course is complete
• Start handling practice — paws, ears, mouth, being brushed
• Start crate and alone-time training in small doses

10 to 12 weeks

• Second vaccination
• Flea and tick prevention started, as advised locally
• Puppy class, once the first vaccination is done and the class requires proof
• Socialisation continues intensively. The sensitive window closes at around 12 to 16 weeks and does not reopen

14 to 16 weeks

• Final core vaccination. This one matters most: current guidance places the last dose at 16 weeks or later, because maternal antibodies can block earlier doses and they fade at unpredictable ages
• Rabies vaccination where applicable, usually from 12 weeks
• First full walks once the course is complete and your vet confirms cover

4 to 7 months: teething

• Adult teeth come through, and puppies chew constantly. Provide appropriate outlets
• Check the mouth regularly. Retained baby teeth — an adult tooth erupting beside a baby tooth that has not fallen out — need removing, usually at neutering, because they trap food and cause disease
• Frozen chews and food toys genuinely help with the discomfort

6 months

• Booster or health check, depending on the protocol
• Move to two meals a day
• Neutering discussion. Not a default decision any more. Timing depends on breed, sex and size, and for larger breeds many vets now recommend waiting until skeletal maturity
• Start brushing teeth if you have not already

6 to 18 months: adolescence

The hardest stretch, and the one nobody warns people about.

• Recall falls apart
• Lead pulling returns
• A second fear period appears somewhere in here — a confident puppy suddenly becomes suspicious of things
• Testing of boundaries
• Chewing returns

What to do: go back a step rather than escalating. Long line on, sessions shorter, rewards higher, pressure lower. It ends.

Also: keep socialising. Confidence built in puppyhood can be lost in adolescence if exposure stops.

12 months

• Annual vaccination and health check
• Switch to adult food: 9 to 12 months for small breeds, around 12 for medium, 15 to 18 for large, 18 to 24 for giant
• Reassess portions, especially if neutered

Growth and exercise throughout

The five-minute rule is a reasonable guide: roughly five minutes of formal exercise per month of age, once or twice a day. Fifteen minutes at three months, thirty at six.

It applies to structured walking, not to free play in a garden where the puppy self-regulates.

Avoid until growth plates close (12 to 18 months for large breeds):

• Long road walks and jogging
• Repeated stairs
• Jumping out of cars
• Hard ball chasing with skids
• Agility jumping

Sleep

Puppies need 18 to 20 hours a day. An overtired puppy bites, cannot learn, and finds everything harder.

Enforce naps with a crate or a quiet room. This is one of the most underrated interventions for a “hyperactive” puppy.

Signs to see a vet promptly

• Vomiting or diarrhoea, particularly in an incompletely vaccinated puppy — parvovirus kills quickly
• Not eating for more than a few hours
• Lethargy, or a puppy who is hard to rouse
• Coughing
• Limping, or reluctance to use a leg
• A pot belly with a dull coat
• Difficulty urinating
• Any collapse or seizure

Puppies deteriorate far faster than adult dogs. When in doubt, ring.

The two things that matter most

Socialisation before 16 weeks. Controlled, positive exposure to people, sounds, surfaces, handling and other dogs. Behavioural problems from under-socialisation cause more dogs to be given up than any infectious disease.

Keeping them lean. The single biggest lever on lifelong joint health, and the one entirely within your control.

Everything else on this list is a date in a diary. Those two are the ones that shape the next fifteen years.