How To Introduce Your Dog To A New Food

Tips to make the transition go smoothly.

Dog disliking dog food

Whether your vet recommended a new food for your pup or you’re getting ready to switch your dog to an adult or senior dog food, you’ll have to make the transition the right way so he doesn’t get sick.

The Dodo spoke to Dr. Andrea Tu, a medical director at Behavior Vets NYC, and Dr. Sara Ochoa, a veterinarian consultant at Senior Tail Waggers, to find out how to transition your dog to new food.

Reasons for changing your dog’s food

There are a variety of reasons why you might switch your dog’s food, such as:

  • Age — Dogs need different amounts of nutrients as they age, so your pup will need to eat food that’s appropriate for his life stage. So when your puppy becomes an adult, for example, you’ll have to transition him from puppy food to adult dog food.
  • Allergies or food sensitivities — Your dog might be allergic or sensitive to certain foods and need to switch to a different food.
  • Bringing home a new dog — If you just got a new dog, you might want to start feeding him a new food.
  • Your dog’s overweight — Your vet might recommend switching to a diet dog food if he needs to lose weight.

Keep in mind you should always talk to your vet before switching your dog to a new food to make sure the food’s a good fit for your pup and that you’re making the transition properly.

How to transition your dog to new food

Any time you transition your dog to a new food, you should do it gradually. This is because dogs have sensitive stomachs, and changing your dog’s diet too quickly can upset his stomach and lead to vomiting and diarrhea.

“Dogs tend to be much more sensitive to new foods than we are and have not evolved to eat as varied of a diet as humans, and as a result, they benefit from a slow transition when introducing a new type or flavor of food,” Dr. Tu told The Dodo.

If you’re going to make the transition from puppy food to adult dog food, it’s basically the same process. According to Dr. Ochoa, “When switching [your puppy’s] diet, it is best to make the transition slowly.”

Dr. Ochoa and Dr. Tu recommend mixing in the new food with the old food gradually until your dog’s eating only the new food. “This should occur over 10 days to one month,” Dr. Tu said.

  • Days 1–3: Feed 25 percent new food and 75 percent old food
  • Days 4–6: Feed 50 percent new food and 50 percent old food
  • Days 7–9: Feed 75 percent new food and 25 percent old food
  • Day 10: Feed 100 percent new food

Be sure to completely mix the new food with the old so your dog can’t pick out his old food.

When to switch a puppy to dog food

You should wait until your puppy’s fully grown to start feeding him adult dog food, Dr. Ochoa advised.

The age at which a puppy matures will depend on his size, so when you can start feeding adult dog food will vary for different pups. “This may be at 6 to 8 months for smaller dogs (25 pounds or less), 12 to 16 months for medium-sized dogs (25 to 75 pounds) and 2 years for large and giant-breed dogs (over 80 pounds),” Dr. Ochoa said.

Here’s a breakdown of approximately when you can start feeding your puppy adult dog food:

  • Small dogs (25 pounds or less) — 6 to 8 months old
  • Medium dogs (25 to 75 pounds) — 12 to 16 months old
  • Large and giant-breed dogs (over 80 pounds) — 18 months to 2 years old

Your vet can also help you decide when to switch to adult dog food if you’re not totally sure.

How to tell if your dog’s reacting well to his new food

The best way to tell if your pup’s OK with his new food is to look at his poop — gross, but necessary.

Your dog’s poop should be brown and firm. If he starts having diarrhea, soft stool or other signs of an upset stomach, like throwing up, you should take him to the vet and stop transitioning to the new food.

If your pup’s still not reacting well to his new food even if you’re transitioning really slowly, he might have an allergy or be sensitive to something in the food. If that happens, start switching slowly back to his old food, and ask your vet for recommendations for different foods.

When transitioning your dog to new food, always be sure to talk to your vet first. And when you’re ready, make the change gradually so your pup doesn’t get an upset stomach.

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