Puppies are born with almost no functioning immune system of their own and rely on maternal antibodies absorbed from their mother's first milk (colostrum). Those antibodies fade over the first weeks of life — but they also block vaccines from working properly, which is why puppies need a series of shots rather than one. This simulation animates a dog growing from a 6-week-old puppy to a mature adult along a timeline, showing maternal antibody decline, the step-by-step immunity built by each vaccine dose, and which shots are due at each stage.
The exact week maternal antibodies fade varies puppy to puppy — which is precisely why vets give a series of core shots roughly every 3–4 weeks until 16 weeks of age, ensuring at least one dose lands after maternal interference has cleared.
This is a simplified educational illustration, not veterinary advice — always follow your vet's actual schedule.
An interactive 3D vaccination schedule timeline with a puppy-to-adult age slider, animating antibody protection levels and showing which core/non-core vaccines are due at each stage.
Maternal antibodies decline over a puppy's first weeks, creating a vulnerable window before a series of vaccine doses builds lasting immunity, with periodic boosters maintaining protection into adulthood.
Drag the age slider from 6 weeks to 5 years and watch the dog grow, the antibody curve rise and dip, and blue (core) and amber (non-core) markers glow when a dose is due. Adjust lifestyle risk to see how it changes the non-core schedule.
Vets space puppy shots roughly every 3–4 weeks specifically because no one knows exactly when an individual puppy's maternal antibodies will stop blocking the vaccine — so several doses are needed to guarantee coverage.