Does my pet have an allergy?

What is Food Allergy?

Food allergy is when your pet is allergic to one or more proteins found in their food.

Food allergies can cause the same symptoms as environmental allergies such as itchy skin and ear disease. Food allergy is different to food sensitivity which may cause digestive upset and other gut-related issues. To complicate things, it is not uncommon for allergic animals to have both food allergy and environmental allergy!

However, it is possible to find out if your pet is food allergic, and if it is, then steps can be taken to ensure it does not cause symptoms in the future.

Is there a test to diagnose food allergy?

Unfortunately there is no test that can prove if your pet is food allergic.

The only way to test for food allergy is to conduct a diet trial, also known as a food trial or elimination diet.

A diet trial involves eliminating all previously eaten foods that may your pet may be allergic to and replacing it with a strict diet using a single novel ingredient.

Diet trials need to last for up to 8 weeks and it is very important that it is run properly in order to diagnose food allergy. Any deviation from the diet trial, including feeding scraps or chews can render the diet trial invalid and you will need to start again.

After 8 weeks, you can reintroduce other ingredients back into the diet one at a time to see if the symptoms start again. This is known as re-challenging. If the symptoms recur, then your pet is allergic to that specific ingredient and you know not to feed your pet that food in future.

What can I feed my dog in a diet trial?

When conducting a food trial, some diets are better choices than others.

As dogs and cats are mainly allergic to meat, fish, dairy and soy, it is important to use a feed that does not contain any of these ingredients. As such, for dogs, a vegetable based diet makes an excellent choice for diet trials since it eliminates the main proteins they may be allergic to. In cats, using a novel protein, like rabbit or quail, that is not commonly found in pet foods would be a good option.

It is important that you feed your pet a balanced and nutritionally complete food and there are vegetable based diets that fit this criteria which are recommended by veterinary dermatologists. Solo Vegetal is a nutritionally complete vegetable-based diet that is available as a dry and wet food. It is highly palatable and makes an excellent choice for diet trials. Watch the video below for more information on Solo Vegetal

Other diets that make suitable choices for elimination diets are special hydrolysed diets. These contain micronised animal proteins that are unlikely to trigger an allergic reaction because the protein molecules are too small. However, evidence suggests up to 40% of allergic animals still react to these diets.

Diets labelled as 'Hypoallergenic' are often not a good choice for a diet trial since they often contain meat or fish based proteins and often include ingredients not labelled.

Be sure to speak to your vet about which food to use for a diet trial.

Owner Compliance:

If you are conducting a food trial for your pet, it essential that you stick strictly to it. Feeding anything other than the chosen elimination diet will invalidate the trial and you will have to start again.

It is very important that you do not feed scraps, treats or medications that may contain other protein sources that your pet could potentially be allergic to.

Make sure you speak to your vet about how best to conduct a diet trial and ensure you are honest about how likely you are to be able to stick to the trial. They will be able to advise on how best to conduct it and help you through the trial.

Although diet trials may be challenging, they are definitely worth it. If your pet is allergic to a certain food and this is proven through a diet trial, your pet may be spared unnecessary courses of medications which can be very expensive through the course of your pets life.

Why is a diet trial so important?

For some dogs with food allergy, removing the problem ingredient from the diet will completely resolve the symptoms, preventing the need for life-long and expensive treatment.

Other dogs with both a food allergy and environmental allergy will benefit since if the food allergy is responsible for 60% of the symptoms, then managing the other symptoms may be easier. Removing the problem ingredient may see a significant or partial improvement in the symptoms.

Whilst some dogs may not be proven to be food allergic, the diet trial is definitely worth doing, since if they are food allergic and the diet trial proves this, the outlook for those pet's is much better.

Food Testing:

Although the only way to prove food allergy is to conduct a food trial, blood tests can help determine an appropriate food to use in the diet trial.

Your vet can take a blood sample from your pet and send it off to a laboratory to run a test that looks for foods that are unlikely to cause a reaction if used for the food trial.

It is important to remember though that this test does not actually prove the foods your pet is allergic to.

Other tests also proclaim to help prove food allergy, such as saliva tests and hair tests. However, clinical trials have proven that these tests do not provide valid results so they should be avoided.