Changing your pet's diet


When might your pet require a change in diet?

From time to time there may be a reason when your pet requires a change in diet. This could be a result of simply being unable to find their brand of pet food in the supermarket, to altering their diet as they grow;  following neutering, pregnancy, because of illness or, commonly they may require a specific diet to help them lose weight. Whatever the reason we are here to help! Take a look as we explore and identify why and how to change your pet’s diet effectively

Why do we need to be considerate when changing their diet?

While people tend to eat a varied diet which changes between meals and days, our pets generally eat the same food on a regular basis. Their guts and gut bacteria get used to this food, and a sudden diet change can therefore cause gastrointestinal upset. Sudden changes to the diet will commonly result in diarrhoea, and occasionally regurgitation or vomiting. These symptoms may be confused with intolerance to the new diet. While it is possible that the new diet does not agree with your pet, it is much more likely that the change was too sudden, and that their bowels did not have a chance to adjust to the new food. This is commonly seen in puppies and kittens when owners switch diets rapidly to try and find one that ‘agrees’ with their new pet, when in fact a little time and patience may be all that was required.

A considerate approach to changing your pet’s diet is less likely to result in a negative outcome, and you may find your pet actually eating the new food, which is great news for you! 

How should you go about changing your pet’s diet?

Unless the vet has recommended an immediate change in diet, as may be the case with certain diseases, it is important that the new food is introduced gradually. It’s advisable to introduce any new food over a 1 week period, sticking to previous meal times that your pet was used to. Start the week by adding a small amount of the new food to the old, and removing equivalent amounts of the old food – to be sure we are not increasing the total quantity that they receive. Throughout the week, gradually increase the amount of new food and reduce the amount of old food. By the end of the week they should be eating the new diet alone. This way your pet, and their digestive system, will have time to become accustomed to the new food.

For example

If moving onto a weight loss diet, it is advisable to seek assistance from your veterinary surgery. Many practices will offer weight clinics, where you can ensure you are feeding the correct food in the correct quantities.

What should you monitor during a diet change?

It is important to monitor your pet’s general demeanour and stool quality and frequency while changing their diet. If you notice any signs that they are not adjusting, then just slow down the diet change process. Reduce the amount of new food a little and spend a few more days at this level before starting to increase the new food and decrease the old food again.

Where should you change your pet’s diet?

This may seem like a strange thing to think about. However, where possible, it is best to carry out a change in diet in a familiar environment, so your pet experiences minimal changes at one time. For example, try not to change their diet suddenly when going into kennels – as we know that kennelling itself can be stressful for some dogs. The combination of stress and diet change may be more likely to result in digestive upset. Of course, if you are caught short on holiday, this would not be an option, but it’s something to aim for where possible!

Does the new diet suit them?

It is sensible to keep an eye on your pet for a few months following a diet change. Monitor their overall health, coat quality, stool consistency and frequency to be sure that the new diet is suiting them well. If the diet change was to assist with weight loss, be sure to continue your ‘weigh-ins’ at the vets to monitor progress. If the diet change was for medical reasons ensure you attend regular check-ups as advised by your vet.

Top Tips and considerations

  • Where possible it is always best to purchase your pet’s next bag of food before finishing the last. If for some reason you cannot source their normal brand/ flavour, you will have some left to gradually transition your pet onto the new diet.
  • It is always recommended to weigh out your pets food using scales. Measuring cups are a step in the right direction, but have been shown to be rather variable depending on how the biscuits position themselves within the cup! This is particularly important if following a weight loss program.
  • Most pet-foods will provide feeding guidelines on the side of the packet. It is worth remembering that these are guidelines and the amount fed should be judged on a case-by-case basis. Some animals will require more, others less, than the daily recommended amount in order to maintain a healthy weight. If you are unsure please consult your veterinary surgery.
  • Some pets can be very stubborn, and may initially refuse a new food. While it is easy to give in and give them something ‘more tasty’, animals are very clever and will quickly learn that by turning their nose away they will receive treats/ human food etc. So long as your dog is fit and healthy they will not starve themselves. In an adult dog you can try the following: leave the food down for 30 minutes in the morning, and if it is not eaten during this time then remove the bowl, repeat this again in the evening, within a couple of days most dogs will realise that this is the only option they are being given, and so will tuck in happily.


11th September 2018

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