When to Stop Feeding Your Dog Puppy Food

puppy eating

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Proper nutrition is an important part of caring for puppies and adult dogs. Most owners know that puppies need food specifically made to promote growth and development. However, many owners struggle to determine when the time is right to switch to adult dog food. This is because there is no rule that applies to all dogs. Different dogs grow at different rates. You and your vet can estimate the best time to make the change to your puppy's diet.

Feeding Puppy Food

Puppies need more calories than adult dogs to support their growth, development, and high energy levels. Young puppies need about twice the number of calories as adult dogs of the same size. As your puppy approaches adulthood, his growth begins to slow and his caloric needs decrease. If you continue to feed puppy food once your dog stops growing, it will result in weight gain. Excess weight can quickly turn into obesity, which can lead to a host of health problems.

When to Switch to Adult Food

In general, dogs are considered puppies until about one year of age. However, different breeds age at different rates. For example, many large and giant breed dogs are considered puppies until two or more years of age and will therefore need to remain on puppy food beyond age one. Conversely, some small dog breeds reach adult size before the age of one. Your veterinarian is the best source of information when it comes to your dog's diet, so ask for advice before making the switch to adult food.

When deciding on the right time to feed adult dog food, the goal is to switch to adult food around the time the puppy stops growing but before he starts gaining excess weight. Keep track of your puppy's weight and height and look for the numbers to increase at a slower rate. Most dogs will begin to reach a plateau around one year of age, but you might notice the growth slow down as early as eight or nine months of age.

Assessing Your Dog's Weight

Be aware that weight gain does not necessarily indicate growth. If your dog is gaining weight but not getting taller or more muscular, he may be getting overweight. You can address your dog's body condition at home in a few steps:

  1. Run your hands along your dog's ribcage. You should be able to feel the ribs covered by a thin layer of fat. If you cannot easily feel the ribs, your dog may be overweight. 
  2. Look at your dog from the side. You should be able to see the upward tuck of the belly. An overweight dog will have very little or no tuck.
  3. View your dog from above. There should be some narrowing at the waist just past the ribcage. A straight or bulging line from the ribcage to the hips indicates an overweight dog. 

Very prominent ribs and a very small waist may mean your dog is underweight. Visit your vet for an exam to be sure.

If your dog is less than a year old and seems to be gaining weight, you may need to simply reduce the portion size or frequency of meals before you switch to adult food. Vets recommend feeding young puppies three times per day. However, most puppies can go down to meals a day when they are approaching adulthood.

How to Make the Diet Change

Any diet change should be done gradually to avoid gastrointestinal upset. This process can take a week or two depending on how you do it.

It may take some time and research to choose the right food for your now-adult dog. You may wish to stick with the same brand of food but switch to an adult formula. Of course, your vet can help you find an appropriate diet.

Once you have chosen the adult dog food, determine the portion size of adult food you will eventually need to feed based on your dog's current weight. Then, add a small percentage of adult food to the puppy food, increasing it a little at each meal. For simplicity, you may want to work out a schedule so you are not trying to remember how much of each to feed. Many veterinary professionals recommend the "3 by 3" approach when switching diets:

  • Days 1-3: Feed 1/3 portion of adult food and 2/3 portion of puppy food
  • Days 4-6: Feed 1/2 portion of adult food and 1/2 portion of puppy food
  • Days 7-9: Feed 2/3 portion of adult food and 1/3 portion of puppy food
  • Day 10 and on: Feed full portion of adult food

During the switch, watch your dog's appetite and bowel movements. Slow the transition if your dog experiences diarrhea or vomiting. If GI upset continues, you may need to choose a different adult diet and re-start the transition. Contact your vet if your dog has vomiting or diarrhea for more than a day.

Watch your dog's weight over the coming months to make sure you don't need to adjust portion times. Also, be sure to keep up with annual or biannual veterinary wellness check-ups as recommended by your vet.