What to Expect in a Labrador Puppy's First Year: A Milestone-by-Milestone Health Guide

By Jessica Ennis, DVM, CVA

Breed care · August 16, 2026 · 4 min read

Expect a Labrador puppy in the first year to move through deworming, core vaccines, teething, socialization, then controlled growth.

Expect a Labrador puppy in the first year to move through deworming, core vaccines, teething, socialization, then controlled growth. Each of those milestones has a biological clock behind it, and understanding the mechanism makes the calendar far less mysterious. Below we walk through the year roughly in the order things arrive — what is normal, what is worth a call to your vet, and why the timing matters.

The First Weeks Home: Parasites and the Immunity Handoff

Most Labrador puppies come home between eight and ten weeks old already carrying two things from their mother: passive immunity and, very often, intestinal parasites. Roundworm and hookworm larvae pass to puppies across the placenta and through milk, which is why deworming starts before a puppy is even weaned. The Companion Animal Parasite Council recommends treating puppies beginning at two weeks of age and repeating every two weeks until routine broad-spectrum parasite control takes over. Because these worms are zoonotic, early deworming protects the household as much as the dog.

Passive immunity works on a shorter fuse than most owners expect.

Antibodies absorbed from colostrum in the first day of life shield a puppy for only a few weeks, then fade — and that fade is the hinge the whole vaccine schedule turns on.

Building Immunity: The Core Vaccine Series

Maternal antibodies are a mixed blessing. They protect a young puppy from disease, but they also bind and neutralize vaccine virus, so a shot given too early can be quietly cancelled out. Since no one can predict the exact week a given puppy’s maternal antibodies drop below that interfering level, vaccines are given as a series rather than a single dose. The American Animal Hospital Association lists distemper, parvovirus, and adenovirus (the combination often labeled DHPP) plus rabies as core vaccines for every dog, with the puppy series repeated every three to four weeks and the final dose given no earlier than 16 weeks of age. That last detail is the point of the whole schedule: it ensures at least one dose lands after maternal interference has cleared, when the puppy can actually respond.

The Socialization Window Runs in Parallel

Here the calendar creates real tension. A Labrador’s brain passes through a sensitive period — roughly the first three months — when sociability outweighs fear and new experiences get filed as normal rather than threatening. The American Veterinary Society of Animal Behavior treats this as the primary window for socialization and recommends starting structured exposure before the vaccine series is finished, because the behavioral cost of waiting usually outweighs the infectious risk when sensible precautions are in place. In practice that means well-run puppy classes on clean surfaces, one set of vaccines at least a week beforehand, and steering clear of high-traffic ground like dog parks until the series is complete.

Miss this window and it does not fully reopen.

Teething and Chewing

Around three to four months, the mouth changes over. Puppies start with 28 deciduous (baby) teeth and finish the year with 42 permanent ones. As Teeth, Teething and Chewing in Puppies describes, adult teeth begin replacing the deciduous set from about three to four months, and most Labradors carry a full permanent set by roughly six months. Expect sore gums, a spike in chewing, and the odd baby tooth turning up on the floor. If a baby tooth — most often a canine — is still wedged in beside its adult replacement, flag it at the next visit; retained deciduous teeth can crowd the bite and are usually removed.

Growth and the Orthopedic Trade-off

This is the milestone owners most often get backwards, because with Labradors faster is not better. As a large breed, a Lab’s skeleton is vulnerable during rapid growth, and excess energy or calcium can outpace the ability of cartilage and bone to mature safely — a direct route to developmental orthopedic disease. Nutritional Considerations for Large and Giant Breed Dogs explains that overfed large-breed puppies do not necessarily get fat; they grow too fast, and the skeleton pays for it. The practical guidance is unglamorous: feed a diet formulated for large-breed growth, keep the puppy lean at a body condition around 4 of 9, and do not add calcium or general mineral supplements on top of a complete puppy food. Labradors are already predisposed to hip and elbow problems, so the choices made this year echo well into later life, when joint supplements for senior dogs become a more common conversation.

Spay and Neuter Timing

The timing of desexing is a genuine first-year decision, and for Labradors specifically the evidence has moved. Analyzing hospital records across dozens of breeds, a 2020 study in Frontiers in Veterinary Science reported that neutering male Labradors before six months of age was associated with joint-disorder rates roughly double those of intact dogs, and its authors suggested neutering males beyond six months and delaying spaying in females past a year. These are population-level associations, not individual guarantees, and they sit alongside reproductive-cancer and behavior considerations — so it is a conversation to have with your veterinarian about your own dog, not a fixed rule.

The Short Version

The first year is really five overlapping clocks — parasites, immunity, the socialization window, teething, and skeletal growth — and most of the job is simply meeting each on time. Finish the vaccine series after 16 weeks, use the socialization window before it closes, feed for steady rather than fast growth, and time desexing deliberately. Do that, and you have set up the quieter years that follow, right through to the longevity and NAD+ questions that matter for senior dogs much later on.