Health series – Food Allergies

It is a well-known fact that people can be allergic to certain foods.  Dogs can also be allergic to ingredients within their diet.

An allergic reaction to food occurs when the immune system has an exaggerated response to a food constituent.  The immune system in a dog who suffers from a food allergy views the food component as a foreign invader and overreacts to it, resulting in the release of chemicals causing inflammation.

If you suspect your dog has a food allergy, you should consult a medical professional.

What is the difference between an allergy and an intolerance?
A food allergy is when the immune system reacts to a food. An intolerance is a reaction to a food that doesn’t involve the immune system.  In reality the distinction between the two is often not made as the immunological process occurring within the body is usually not determined.

Signs of food allergy
Dogs with food allergies can have skin problems and may also show gastrointestinal signs such as vomiting or diarrhoea. Not all dogs will show these symptoms, but typical signs can be:

– Itchy skin (or pruritus) affecting the face, ears, feet, axillae (armpits), stomach, groin and the skin around the anus.

– Recurrent ear infections in one or both ears can also be a symptom of a food allergy. This will be displayed as a redness of the skin and dogs will scratch and lick the affected areas.  Secondary skin infections, alopecia and thickening of the skin are also often seen.

Which dogs may be affected?
Symptoms are usually seen in younger dogs although older dogs can also be affected.  The signs are non-seasonal and are present throughout the year.  As the signs of dogs suffering from allergic reactions to environmental allergens (atopy) are very similar to those of food allergies it can be very difficult to distinguish between the two conditions.  Dogs may be allergic to both food and environmental allergens.  Your vet should be consulted and may carry out further diagnostic tests.

What foods are dogs allergic to?
There are several different food constituents that dogs can be allergic to however, dogs tend to be allergic to the foods which are commonly found in their diet.  The most common causes are beef, chicken, pork, turkey, lamb, eggs, corn, wheat and soy.  It is possible that some dogs are allergic to more than one food component.

Diagnosis
If you suspect that your dog has an allergy, then you should consult your vet.

In the first instance, your vet will try and determine if there is any other underlying condition that could be causing these symptoms.  It is important that other possible skin diseases are ruled out by your vet and any bacterial or yeast skin infections treated. If they suspect that it is a food allergy, your vet may suggest a dietary trial or elimination diet.

A dietary trial consists of trialing a specific food for a certain period of time.  The idea of a food trial is to remove all the food from the diet the dog has previously been fed and therefore any possible offending food components. Your vet will then advise to feed a new novel diet and monitor the dog for resolution of clinical symptoms under the supervision.

The choice of food to use in the dietary trial is also very important and will be decided on by your vet or specialist depending on the diet the dog has previously been fed.

The length of time a dietary trial should last is also important.  The diet needs to be fed long enough to enable the dog to respond, and your vet will discuss this with you.  It is crucial that during this time no other food is fed.  No dog treats or scraps from the table must be fed as this will influence the dietary trial.  Initially drugs such as antibiotics and antifungals may be prescribed for your dog to control secondary skin infections.  It is important that the dietary trial continues after the treatment has ended so that any improvement in signs can be attributed to the diet and not the drug treatment.

If the symptoms improve then your dog may have a food allergy.  To confirm the presence of a food allergy the dog is normally fed the original diet and monitored for return of signs.  Symptoms usually recur within a couple of weeks although they often show within the first couple of days.  If the signs recur on feeding the original diet then a diagnosis of food allergy can be made.  Dogs may also be allergic to several different allergens.

A dietary trial can be challenging to undertake.  It is important that everyone in the family understands why a dietary trial is being performed and the necessity to eliminate everything else from the diet other than that prescribed.  No dog treats or treats from the table are allowed to be given during the period of the trial.  Dietary trials can fail if dogs are given other foods during this period.  You should always ensure that fresh water is available to your dog to drink.  Once a food allergy has been diagnosed they can be easy to manage just by avoiding the offending foods.  However, as allergies to food develop over a period of time it is possible that dogs can become allergic to the new diet.

Hypoallergenic diets
Hypoallergenic diet is a term used to describe a diet which is low in allergens.  An allergen is a substance capable of causing an allergic reaction.  Diets that have a small number of ingredients will have a lower number of potential allergens.

Naturediet recipes offer a range of complete and balanced diets both as a wet or dry option. Using only a limited number of ingredients, all the recipes are wheat and gluten free.

The Feel Good range offers 12 delicious varieties in 2 different sizes (390g and 200g).  As part of the range, there are 4 grain free recipes have been created for those pets who have a gluten intolerance.

The Purely range is designed to give optimal nutrition from essential ingredients and has been specifically formulated for dogs with food intolerances. The simple, 92% just meat recipes have added vitamins and minerals to provide a nutritionally balanced complete feed.

All Naturediet varieties are complete and therefore do not need to be fed with any other foods and are produced without the use of artificial preservatives, colourings or flavourings.  The wet foods are gently steamed cooked to maintain the highest nutritional value and packed in an innovative recyclable carton that ensures the quality of the food is naturally preserved.

Naturediet dry food can be fed alone, or alongside the wet food ranges taking into account calorific values. You can refer to our feeding guides for more information.