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When should my large breed puppy transition to adult dog food?

Updated on September 23rd, 2025

Pet's info: Dog | German Shepherd | Male | unneutered | 8 months and 26 days old | 50 lbs

I have a 9-month-old german shepherd/ belgian malinois mix puppy, and I was wondering when should I change him from puppy food to adult food.

4 Answers

Most Helpful Answer

Dr. Melanie, BVSc MS

Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on May 11th, 2023

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question, which is a great one. You should switch Ranger from his puppy food to an adult food when he is 12 months of age. Given that he is a large breed dog, I recommend that when he is 12 months old, you feed him a large breed dog food. Brands I recommend include Royal Canin, Hill's Science Diet, Purina ProPlan, and Iams. When you do make the switch, you will need to transition him slowly to prevent stomach upset. You do this by mixing together the puppy food and adult food, slowly increasing the amount of adult food and decreasing the amount of puppy food until he is eating the adult food only. I hope this helps!
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Related Answers from Veterinarians

  • Answered By Rebecca, DVM

    Veterinarian

    Published on August 11th, 2017

    It somewhat depends on the breed and the size of the dog. A general rule of thumb is feed puppy food till they are about a-year-old, however giant breed dogs should be fed large breed puppy formula still there 18 months to two years old and smaller toy breed dogs may be able to be switched between 8 to 10 months of age. If pilot is a midsize mixed breed dog I would recommend keeping him on primarily a puppy formula until close to a year of age.

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    1Pet Parents found this answer helpful

  • Answered By Dr. Elizabeth

    Veterinarian

    Published on November 1st, 2019

    You will need to transition the food over about a week so you will need a small supply of the current dog food the puppy is eating. Yes, you should feed your new puppy an appropriate puppy food until he is about 1 year old (depending on his adult size).
    I hope this helps and please feel free to post any additional questions.

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    2Pet Parents found this answer helpful

  • Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on June 24th, 2018

    Wallace is a very handsome boy! Large breed dogs should be switched to an adult food when they are at least 12 months of age, so I would wait until then to make the switch. Best of luck, I hope this helps!

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    1Pet Parents found this answer helpful

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