Why timing matters

A newborn puppy gets antibodies from its mother's first milk. Those maternal antibodies protect it for the first weeks — and they also block vaccines from working, because the puppy's immune system never sees the challenge.

They fade somewhere between six and sixteen weeks, and nobody can predict exactly when for a given puppy. That creates a gap: maternal protection too weak to defend, still strong enough to interfere with a vaccine. That gap is why puppies are vaccinated in a series rather than once, and why the final dose at 14–16 weeks is the one that really counts.

Do not stop at the second round

The most common serious mistake new owners make is treating the second vaccination as "done" and taking the puppy to a dog park. Until roughly two weeks after the 14–16 week dose, your puppy is not reliably protected against parvovirus — which is still common, still often fatal, and survives in soil for months.

Core vaccinations

Four diseases every puppy is vaccinated against, usually in a combined DHPP shot plus rabies.

Canine distemper (D) — a viral disease affecting the respiratory, gastrointestinal and nervous systems. Frequently fatal, and survivors often have permanent neurological damage.
Canine adenovirus / infectious hepatitis (H) — attacks the liver, kidneys and eyes.
Canine parvovirus (P) — severe bloody vomiting and diarrhoea, rapid dehydration, high mortality in unvaccinated puppies. The single biggest reason to finish the course.
Parainfluenza (P) — a contributor to kennel cough.
Rabies — legally required across the United States and Canada. Timing of the first dose varies by state and province; your vet will know.

The schedule

Age	What	Who does it	Notes
2, 4, 6, 8 weeks	Worming	Done here	Fenbendazole or pyrantel, every two weeks
6–8 weeks	DHPP — first round	Done here	Distemper, hepatitis, parvovirus, parainfluenza
8–9 weeks	Microchip + vet exam	Done here	Full exam within a week of travel
10–12 weeks	DHPP — second round	Your vet	Booked by you, within days of pickup
14–16 weeks	DHPP — third round + rabies	Your vet	Rabies at 12–16 weeks depending on state law
12 months	DHPP + rabies booster	Your vet	Then every 1–3 years per your vet and local law

Your vet may adjust this. Local disease prevalence, state rabies law and your puppy's own history all matter, and your vet knows your area better than we do. Follow their schedule, not ours, and keep the record.

Non-core vaccinations

Given based on where you live and what your dog does. Ask your vet which apply.

Bordetella (kennel cough) — needed for most boarding kennels, daycare, grooming and training classes. Often required before a puppy class, so ask early.
Canine influenza (H3N2/H3N8) — worth it in areas with outbreaks or if your dog boards.
Leptospirosis — a bacterial disease spread through water contaminated with wildlife urine. Recommended almost everywhere now, and increasingly treated as core.
Lyme disease — in tick-heavy regions, particularly the Northeast and Upper Midwest.

Worming and parasites

Almost all puppies are born with roundworm larvae passed from the dam — this is normal and not a sign of a dirty environment. It is why worming starts at two weeks.

Here: wormed at 2, 4, 6 and 8 weeks, and a faecal check before travel.
With your vet: continue monthly to six months, then move to a year-round combined preventative.
Heartworm prevention year-round, starting as your vet advises. Treatment is brutal; prevention is a monthly chew.
Fleas and ticks year-round. Dosed by weight, so budget for the giant bracket.
Giardia and coccidia are common in all puppies, cause loose stools, and are easily treated. Tell us if it happens — we will help with the cost and we want to know.

What your puppy arrives with

Age-appropriate core vaccinations — one or two DHPP rounds depending on pickup age
Worming at 2, 4, 6 and 8 weeks, with a clean faecal check
A microchip, registered and ready to transfer into your name
A full veterinary examination within the week before travel
BAER hearing test results for merle and harlequin puppies
A written record of every dose, date, batch number and vet signature — in a folder, in your hands, at pickup
A written schedule of what is still due and roughly when

Book your vet before pickup

Make the appointment for within seven days of collection before your puppy comes home. It is the best early check on everything, it starts your relationship with the vet you will rely on for a decade, and it is the condition that keeps your health guarantee active.

Vaccinations & worming.