Two Easy Ways to Start Earning Rewards!
Become a member today!
Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
Already a member? Sign in
Become a credit card member today!
Earn 2X Pals Rewards points at Petco
when you use Petco Pay!
APPLY NOW
Learn More About Petco Pay Benefits

What's the best calcium to phosphorus ratio for my large breed dog?

Updated on September 23rd, 2025

Pet's info: Dog | German Shepherd | Female | unspayed | 10 months and 23 days old | 58.5 lbs

What is the proper calcium to phosphorous ratio when feeding a large breed puppy or dog? Ive read that it should be 1:1, Ive read it should be 1.2:1, and Ive read it should be between 1:1 and 2:1. This is very confusing. I have an 11 month old German Shepherd girl and Ive been feeding puppy food thats 1.4:1 which I think is ok. I am now thinking of changing her to an adult food (single protein as she is very itchy), but some of the protein:calcium ratios are way off?!!?

1 Answer

Most Helpful Answer

Answered By Stacey Anstaett, DVM

Veterinarian

Published on April 4th, 2019

Thanks for asking PetCoach!! Confusing is putting it mildly when trying to sort through good, scientific based information regarding nutrition for our pets. First of all, for large breed dogs, keep them on a good large breed puppy food until AT LEAST 12 months of age. For a German Shepherd, sometime between 12-15 months would be a good time to transition. (larger breeds do more growing for a longer period of time than small breeds, so need puppy food longer, which in a way seems counter-intuitive as they "age" faster than smaller breeds!)
http://vetnutrition.tufts.edu/2016/04/when-your-baby-isnt-such-a-baby-anymore-when-to-switch-to-adult-foods/
As far as he Ca:P ratio, while still important, my recommendation would be to stick with something around 1.2:1. For large breed adult foods vs regular adult foods, the difference tends to be more geared towards long term skeletal and joint health; meaning in large breed adult foods you're more likely to find glucosamine/chondroitin supplementation built in, extra fatty Omegas, etc.
I hope that answers your question. Thanks for asking PetCoach! https://www.petcoach.co/article/calcium-phosphorous-requirements-for-dogs/

1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Related Questions

Food & Nutrition

What calcium levels are best for giant breed puppy joint health?

What you need to focus on in a large breed puppy is the calcium/phosphorus levels. If those are not in balance they can get growth abnormalities in their joints. For growth in large breed puppies, a dog food must (on a dry matter basis) contain: 1.2 to 1.8% calcium 1.0 to 1.6% phosphorus Calcium-to-phosphorus ratio between 1:1 and 1.8:1 The protein and fat percent are not that important. My recommendation is to feed a commercial diet that abides by AAFCO standards (this will be on the label) and just make sure it is for large breed puppies. Don’t use nutritional supplements when feeding your large breed puppy any commercial diet as you will surely upset the balance of minerals. I was assuming you were talking about feeding large breed puppies. If you want information on feeding an adult large breed please ask your question again and be more specific. I hope this helps. Best wishes!

Updated on September 23rd, 2025

Food & Nutrition

My Labrador puppy's food has 1.72 calcium. Is that too high?

Hello, and thank you for your question! As a large breed dog, the ideal calcium to phosphorus ratio should be 1.1 to 1.3. So your current food is not ideal but it is definitely not too late to switch! Look for a puppy formula for large breed dogs. Good brands that have this formula include Science Diet, and Royal Canin. Keeping him on a large breed puppy formula until he is at least 1 year of age will help to prevent hip issues as he gets older. I hope this helps, and that Louie is happy and healthy!

Updated on September 23rd, 2025

Food & Nutrition

What large breed food is best for my 9-month German Shepherd?

I use the large breed adult food from 9 months on. I like the dogs to grow a little slower to prevent bone problems. Soska will reach her full size but it will just take a little longer with less bone and joint issues. I usually mix the new food with the old food for a week or two so she doesn't get a stomach upset. Thanks for using Petco Pet Education Center, formerly Petcoach to help you care for Soska.

Updated on September 23rd, 2025

Food & Nutrition

Large breed puppy food: When to switch & calcium levels?

Most larger breed dogs physically mature between 12 and 16 months of age. It will take up to 2 years for him to mature mentally and socially. Giant breeds take even longer, smaller breeds mature sooner. It is generally recommended to transition to an adult diet at around 1 year of age since a majority of dogs will be at or very near adult size by this age. Feeding a puppy diet beyond may predispose a dog to obesity and orthopedic issues. The calcium level in the current diet is fine for Otis. As he nears adulthood, it can be decreased to 1.5%. As long as he is getting a balanced diet, he should be fine. Studies have shown that a low calcium diet have no effect on the incidence of hip dysplasia and other orthopedic abnormalities in growing dogs. A balanced diet and one with an appropriate calcium:phosphorous ratio is much more important and beneficial. You can read more here: http://www.peteducation.com/article.cfm?c=2+1659&aid=652

Updated on September 23rd, 2025

Food & Nutrition

Does my German Shepherd dog really need calcium supplements?

A fully balanced diet such as large breed food formulated for the age of your dog (puppy or adult) would not need to be supplemented with any calcium supplement and indeed over supplementation can also cause problems. I suggest you speak to your local food suppliers to suggest a suitable, balanced diet in order to ensure all his needs are being met, not just calcium and phosphorous

Updated on September 23rd, 2025

Food & Nutrition

Is my 1-month German Shepherd puppy's food and supplements good?

Hello. This may be a pretty low quality food. And adding unnecessary supplements may do more harm than good. You are much better off feeding a good quality large breed puppy food such as the ones made by Purina, Science Diet & Royal Canin. Thanks for using Petco Pet Education Center, formerly Petcoach.

Updated on September 23rd, 2025

Food & Nutrition

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

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!

Updated on September 23rd, 2025

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share