How to Transition Your Pet to a New Food

Sometimes changing your pet’s diet is necessary, but it’s important to transition your pet to new food slowly so their stomach isn’t overwhelmed. In this guide we'll cover the best way to transition your pet to a new food and avoid upset stomachs.

Reasons To Change Your Pet’s Diet
Changing your pet’s diet isn’t a cause for alarm – but there are important steps to follow to ensure the transition goes smoothly and your dog or cat doesn’t suffer any discomfort or stomach issues. You may want to change your pet’s diet for any of the follow reasons:

• Your pet has a medical condition which can be aided with prescription vet diet – as recommended by your vet.
• You’d like to switch to a super-premium food for better nutrition.
• Your circumstances have changed, and you need to move your pet onto more budget-conscious food.
• Your pet has moved into a new life category and thus there are other food types better suited to them (for instance your puppy or kitten may no longer be in that age bracket, or your pet could move into the mature-age bracket and require food with less calory density).
• Your pet is pregnant or nursing.
• Your pet is overweight and you’re transitioning them to diet food, or your pet has reached goal weight and you want to transition them back to normal food.

A Guide for Transitioning Pet Food

While we’re used to our own stomachs (which can handle a variety of foods at any given time), dogs and cats require a balanced and regular diet – otherwise they’re prone to stomach upsets.

Regardless of the reason for changing a pet’s diet, it is imperative that the transition is gradual. Slowly introducing increased amounts of the new food whilst decreasing the volume of the previous diet will significantly reduce the risk of gastro-intestinal upsets and disruption of a balanced gut biome. - Dr Nick Emerton, General Manager of Petstock Vet- Dr Nick Emerton, General Manager of Petstock Vet

If you suddenly change your dog or cat to a new diet without a transitioning process, you risk upsetting their stomachs. Vomiting, diarrhoea and runny poos are common symptoms of a pet that’s had their diet changed too soon – and in severe cases, pets can become very unwell and require medical intervention, or it could be fatal.

This isn’t to say you shouldn’t change your pet’s food! It’s just very important to do it slowly to ensure your pet has adapted to the new food and prevent any discomfort or severe side effects.

Expert Petstock vet Dr Nick Emerton recommends transitioning your pet to their new food gradually – ideally over a period of 14 days. This is just a rough guide however, as some pets will need more time – especially cats who can take up to a month to adjust to a new diet. It’s recommended to consult your vet prior to your change, who will be able to give you more tailored advice to your individual animal.

The transition to new food should take place over a period of 14 days.

Days 1-4: Serve 80% of the old food and 20% of the new food.
Days 5-7: Gradually increase the new food portion to 40% and reduce the old food to 60%.
Days 8-10: Now, make the serving 60% new food and 40% old food.
Day 11-13: Increase new food to 80% share and decrease old food to a 20% share.
Day 14: If your pet has shown no signs of discomfort, you can now fully transition to the new food.

Transitioning your pet’s food works by feeding them a mixed portion of food – partially their old diet, and partially their new food. As you transition along, you will feed them more of the new diet and less of the old – until you’ve fed them an entire serve of their new food. By transitioning your pet’s food this way, you ease the strain on their sensitive stomachs and reduce the risk of your pet exhibiting adverse symptoms.

During this transitioning process, it’s recommended to stay with your pet during mealtimes and monitor them to ensure they’re not reacting adversely. If your dog or cat shows signs of an upset stomach (such as diarrhoea, vomiting or runny poos) at any point during this transition period pause the transition until their stomach has settled. If symptoms persist, it’s recommended to take your pet in for a vet check-up.

Top Tips to Transition Your Pet to a New Food

• Ensure you’re feeding your pet at regular times – and stick to them as strictly as possible during the transitional period.
• Make sure someone is present during and immediately after mealtimes to monitor your pet’s reaction.
• Limit treats during the transitioning period – and avoid introducing new treats until you pet has switched entirely to their new diet.
• If your pet is fussy and reluctant to try their new food, use handfeeding initially to entice them to eat (this is particularly relevant to cats who are often finicky about their food).
• If there is a strong negative reaction, consult your vet.

FAQs for Transitioning Your Pet to a New Food

How long should the process of switching foods take in a dog or cat?
While we recommend a transition period of 14 days, it does depend on the individual pet. Your pet may need longer (cats may take up to a month), but even if they’re transitioning well, it’s ill advised to take the 14 day period to minimise any risk of stomach upset.

Can changing dog food cause any constipation or diarrhoea?

Yes, a change in diet is major culprit of stomach upsets in dogs and cats – and constipation or diarrhea are some of the symptoms they can experience if their diet is changed rapidly. This is why we recommend taking the 14-day transition process to ease them into their new diet.

What are the side effects of switching food?

Serious possible side effects include constipation, diarrhea, and vomiting – though the risk of these is minimised if the transition process is done properly.

Can I switch my pet's food without transitioning it gradually?

Abrupt switches can lead to digestive issues. Gradual transitions are recommended.

Can I transition my senior pet to a new food?

Yes, but it’s possible that your senior pet may need more time to adjust. Consult your vet for guidance.