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New Puppy

New Puppy First Week Checklist (USA 2026)

The first week with a new puppy is equal parts joy and chaos — and it's also when a few early decisions quietly set the tone for the next fifteen years. This is the week you book the first vet visit, start (or continue) the vaccine and deworming series, settle a feeding routine, introduce the crate, and begin gentle socialization. Below is what actually matters, in the order most owners run into it, following AAHA and AVSAB guidance.

Respuesta rápida

En la primera semana de un cachorro nuevo, reserva una visita al veterinario en los primeros días — normalmente entre las 6 y 8 semanas de edad — donde hará un examen completo, revisará una muestra de heces, desparasitará (a menudo aunque sea negativa) e iniciará la serie de vacunas básicas que se repite cada 2–4 semanas hasta al menos las 16 semanas. Mantén el mismo alimento al principio y da a un cachorro de 8 semanas 3–4 comidas pequeñas al día. Prepara una jaula del tamaño adecuado para acelerar el aprendizaje de higiene y saca al cachorro tras las comidas, las siestas y el juego. Lo más importante: empieza la socialización suave ahora: la ventana de las 3 a 16 semanas moldea el temperamento de por vida, y AVSAB considera la socialización temprana y segura el estándar de cuidado incluso antes de la vacunación completa. Confirma el calendario exacto con tu veterinario.

The first 48 hours: keep it small and calm

A puppy that just left its littermates is overwhelmed. Resist the urge to invite the whole neighborhood over. Pick one room, put down water and a bed or crate, and let the puppy explore on its own terms. Keep feeding the exact same food the breeder or shelter used for at least the first several days — a sudden diet switch on top of the stress of moving is the fastest way to trigger diarrhea. If you do plan to change foods, mix the new in gradually over about a week. Expect some crying the first few nights; a crate near your bed usually settles a puppy faster than isolating it in another room.

Your first-week priorities

PriorityWhenWhy it matters
Book the first vet visitWithin the first few daysConfirms the puppy is healthy and starts vaccines/deworming on schedule
Keep the same foodDays 1–7, then transition slowlyAvoids stress diarrhea; puppies eat 3–4 small meals a day
Set up the crateDay 1A right-sized den speeds house-training and gives a safe retreat
Start gentle socializationThis week — it can't waitThe 3–16 week window shapes temperament for life
Puppy-proof one roomBefore arrivalCords, toxic plants, and small objects are the real hazards

The first vet visit — what happens

Book it early: Most vets want to see a new puppy within the first week home, usually somewhere between 6 and 8 weeks of age. The exam runs about 30–45 minutes: a nose-to-tail physical to weigh the puppy, listen for a heart murmur, and check for congenital issues like a hernia or hip problems. Bring any paperwork from the breeder or shelter and, if you can, a fresh stool sample.

Fecal test, deworming, and vaccines: Intestinal worms — roundworms, hookworms, whipworms — are extremely common in puppies, so the vet checks a stool sample and usually deworms even if it's negative, because eggs are shed on and off and can be missed. Deworming typically runs every 2 weeks until about 12 weeks. The core vaccine series (distemper, adenovirus, parvovirus, parainfluenza, plus rabies) starts around 6–8 weeks and repeats every 2–4 weeks until at least 16 weeks — that final booster is the one that really locks in immunity.

Socialization: the window that won't reopen

The single most important behavioral job of these weeks is socialization, and it is genuinely time-sensitive. A puppy's brain is wired to accept new people, dogs, sounds, and surfaces without fear roughly from 3 to 16 weeks of age — and that window does not come back. Here's the tension owners feel: the puppy isn't fully vaccinated yet. The American Veterinary Society of Animal Behavior (AVSAB) is clear that the behavioral risk of under-socializing outweighs the infectious risk when done sensibly, and considers early socialization the standard of care. Do it safely: carry the puppy in busy places, invite calm vaccinated adult dogs to your home, expose it to car rides, umbrellas, and vacuum cleaners, and enroll in a well-run puppy class — most accept puppies from 7–8 weeks with at least one set of vaccines given about a week beforehand. Keep every experience short and positive; forcing a frightened puppy backfires.

What to buy (and rough US costs)

  • Crate sized to stand, turn, and lie down — not bigger: USD 30–70
  • Puppy-formula food (same brand as the breeder to start): USD 20–60
  • Stainless or ceramic food and water bowls: USD 10–25
  • Flat collar, ID tag, and a 4–6 ft leash: USD 15–35
  • Enzymatic cleaner for accidents (ordinary cleaners don't cut it): USD 10–15
  • Bed, a few chew toys, and puppy pads: USD 30–60

You don't need a boutique haul on day one. A correctly sized crate matters more than a fancy one — too roomy and a puppy will potty in the far corner, which defeats the whole point. Skip the retractable leash for now; a simple 4–6 foot lead gives you far more control while house manners are still forming. Budget separately for that first vet visit, which with the exam, first vaccines, and deworming commonly runs about USD 100–300 depending on your region.

Feeding, crate, and house-training rhythm

An 8-week-old puppy has a stomach the size of a walnut and burns energy fast, so plan on 3–4 small meals a day of a food labeled for growth; tiny toy breeds especially need regular meals to avoid low blood sugar. House-training runs on a clock, not on hope: take the puppy out first thing in the morning, after every meal, after naps and play, and right before bed — a rough guide is that a puppy can hold it about one hour per month of age. Reward the instant it goes outside. The crate is your ally here, since puppies avoid soiling where they sleep, but never use it as punishment. One caution worth flagging: vomiting, bloody or watery diarrhea, refusing food, or unusual lethargy in an unvaccinated puppy can signal parvovirus, which is an emergency — call a vet the same day rather than waiting to see if it passes.

Track the first weeks with PetCare AI

There's a lot to keep straight in month one — vaccine dates two to four weeks apart, deworming rounds, feeding amounts, and a socialization to-do list. Log it all in PetCare AI's care calendar and get reminders so no booster slips. Ask the AI vet assistant things like "My 9-week puppy has soft stool after switching food — should I worry?" to think through next steps, and use the in-app finder to locate a nearby clinic. It doesn't replace your veterinarian, who will tailor the vaccine and deworming plan to your puppy — but it helps you show up prepared.

Preguntas frecuentes

¿Cuándo debe ser la primera visita al veterinario de un cachorro nuevo?

Idealmente en los primeros días o la primera semana tras llevarlo a casa, normalmente hacia las 6–8 semanas de edad. La visita confirma que está sano, revisa una muestra de heces en busca de gusanos e inicia o continúa la serie de vacunas y desparasitación a tiempo. Lleva los registros del criador o refugio y, si es posible, una muestra fresca de heces.

¿Puedo socializar a mi cachorro antes de que esté completamente vacunado?

Sí, y deberías, con cuidado. La ventana de socialización de 3 a 16 semanas no vuelve a abrirse, y AVSAB considera la socialización temprana el estándar de cuidado. Hazlo con seguridad: lleva al cachorro en brazos en lugares muy concurridos, invita a casa a perros adultos tranquilos y bien vacunados, y apúntate a una clase de cachorros de confianza que exija al menos una serie de vacunas una semana antes de empezar.

¿Con qué frecuencia debo alimentar a un cachorro de 8 semanas?

La mayoría de los cachorros de 8 semanas están mejor con 3–4 comidas pequeñas al día de un alimento para crecimiento. El estómago pequeño y el metabolismo rápido exigen comidas frecuentes, y las razas toy diminutas las necesitan especialmente para evitar la hipoglucemia. Usa la cantidad del envase como punto de partida y ajústala con tu veterinario según la condición corporal.

¿Qué tamaño de jaula necesita un cachorro?

Lo suficiente para que se ponga de pie, gire y se acueste cómodamente, y no más. Si la jaula es demasiado amplia, el cachorro dormirá en un extremo y hará sus necesidades en el otro, lo que retrasa el aprendizaje de higiene. Muchos dueños compran una jaula de tamaño adulto con un divisor y amplían el espacio a medida que crece.

¿Qué señales de alarma debo consultar con el veterinario en la primera semana?

Vómitos, diarrea con sangre o acuosa, rechazo a comer, letargo extremo, encías pálidas o un abdomen hinchado justifican una llamada el mismo día — en un cachorro no vacunado pueden indicar parvovirus u otra urgencia. Las razas muy pequeñas también pueden sufrir una hipoglucemia peligrosa si se saltan comidas. Ante la duda, llama en vez de esperar.

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