Food Allergies in Dogs

Food Allergies In Dogs

For a pet owner, seeing your dog itching and scratching can be a cause for worry. Itching is a common complaint among dog owners and there are many causes for this including flea bites (flea allergy dermatitis), seasonal allergies or atopy, contact dermatitis, sarcoptic mange, and food allergies [3].

"Your dog may develop food allergies at any stage of its life." The Merck Veterinary Manual

Food allergies are the 3rd most common cause of itching (skin disease) in dogs and it consists of 10-15% of all allergic skin diseases in dogs [5]. It has been reported in dogs 2 months to 14 years old [6] which mean that your dog may develop food allergies at any stage of its life. Also, most adverse food reactions begin when dogs are less than 1 year old [6].

While in adults, food allergy develops if they are fed the food allergen for >2 years [2,6] which means that if your adult dog’s diet has an ingredient(s) that it is allergic to, it will take over 2 years of feeding before you see signs of food allergy.

There is no sex predilection for diet-related allergy in dogs so both male and female dogs have the same chances of getting it.

There were some reports, however, that there are dog breeds that have greater risk of developing food allergies. This includes Labrador Retrievers, West Highland White Terriers, Cocker Spaniels, Springer Spaniels, Boxers, Dachshunds, Dalmatians, Lhasa Apsos, German Shepherds, and Golden retrievers [6].

So if your dog belongs to one of these breeds, it might be best to consider feeding your dog a less allergenic diet.

What foods are dogs commonly allergic to?

The most common food or food ingredients that have been found to cause allergies in dogs are beef, dairy products, and wheat. These three ingredients account for two thirds of reported cases in dogs. Chicken, chicken eggs, lamb, or soy accounted for twenty five percent (25%) of the dogs with diet-related skin allergy.[1]

What are the signs and symptoms of food allergy in dogs?

If your dog is suffering from food allergy, you can observe:

Moderate to severe itching [2,6]​

Ear infections [3,6]

Skin lesions [5]

  • Plaques-o
  • Pustules-o
  • Erythema- reddening of the skin
  • Crusting- dried serum or pus on the surface of the skino
  • Scaling- flakes of dead epidermal cells shed by the skino
  • Hair loss- due to constant scratching, licking or chewingo
  • Excoriation- removal of the surface of the skin as a result of scratching or scrapingo
  • Lichenification- thickening of the skin epidermiso
  • Hyperpigmentation- darkening of the skino
  • Urticaria- skin rash; pale red, raised itchy bumps on the skino
  • Angioedema- swelling of the dermis

    Gastrointestinal signs [2,5]
  • Vomitingo
  • Diarrhoeao
  • Stomach rumble (borborygmus), intestinal gas (flatulence), and frequent bowel movements•
  • Neurologic signs [2,5]- very rare; seizures

    Azestfor Homemade diets are tailored to meet your dog’s individual needs, and this means that his diet is free from ingredient(s) that can trigger his food allergy, is nutritionally balanced and nutritionally complete.

Diagnosis of Food Allergies In Dogs

The diagnosis of food allergy in dogs is difficult and time consuming. At the present time, intradermal skin testing, ELISAs, and RASTs for food allergy are considered unreliable in animals.

The only way to determine if your dog is really suffering from food allergy is by doing the following steps:

Food Elimination Trial

Step 1: Food Elimination Trial
In this stage, our aim is to know if the food that we are feeding contains an ingredient(s) that our dog is allergic to.

1. Two weeks before starting the elimination trial, the pet parent must list down the foods the dogs is eating and the clinical signs observed (e.g. itching, redness of the skin, etc.)

2. Have your dog checked and treated by a vet for other possible causes of allergy (flea, mites or atopy) and for secondary causes of itching (yeast infection or bacterial infection)

3. Choose a home-prepared or commercial food to be used as the elimination diet.

The elimination diet should be tailored to the individual and take into account the dietary history of the dog.

It must consist of substances that the dog has not been previously exposed to before, must not contain additives such as colorings, flavorings or preservatives, and must be nutritionally balanced and nutritionally complete.

An elimination diet usually consists of a novel protein source (lamb, filleted whitefish, canned tuna fish in water, rabbit, venison, turkey, ostrich, yams, pinto beans) and a carbohydrate source (rice, potatoes). [2]

4. Feed appropriate formulation (elimination diet) for at least 4-6 weeks; keep a daily diary of what the dog eats and clinical signs observed.

5. If you don’t see any improvement in the dog’s clinical signs then it is unlikely that his skin disease/ ear infection/ gastrointestinal problems were caused by an allergy to food.

6. If you see some improvement, continue feeding the elimination diet for another 4 weeks (it usually takes 12-13 weeks for maximum improvement of the clinical signs).

If after another 4 weeks of feeding, partial improvement continues, then your dog’s condition may not be caused by an adverse reaction to its original food or that he/she also is also affected with other allergic conditions (atopy, flea allergy) in conjunction to food allergy.[1]

7. If you observe a dramatic improvement in the clinical signs of your allergic dog, you go ahead and feed your dog his/her original diet or individual proteins (to identify which particular food ingredient/s your dog is allergic to), we proceed to doing the

Challenge Trial.

Step 2: Challenge trial
The aim is to confirm that a food allergy exists and that the clinical improvement was not just coincidental, the animal must be challenged with the previously fed food ingredients and a relapse of clinical signs must occur. [6]

1. Feed your dog with his/her original diet (previously fed food ingredients).

2. If after the challenge test, the itching does not recur, the individual ingredient is not considered important in causing the clinical signs.

3. If the clinical signs of the allergy will return (in 1 hour to 14 days), this confirms that something in the diet is causing the signs.

Proceed to step 3 which is the

Provocation Diet Trial

Step 3: Provocation Diet Trial
Our purpose in doing this step is to identify which particular ingredient your dog is allergic to

1. In this test, we add single ingredients to the elimination diet.
Test ingredients include a full range of meats (beef, chicken, fish, pork, lamb), a full range of grains (corn, wheat, soybean, rice), eggs, and dairy products. [5]

2. For each ingredient, the feeding should last up to 10 days or less if signs develop sooner.

3. If your dog is allergic to the ingredient, you will see your dog develop signs of allergy (e.g. itching, skin lesions).

Dogs will usually develop signs within 1-2 days of feeding with an allergenic ingredient.

After this trial, you should be able to identify which ingredient(s) your dog has an allergy to. This will help in choosing the best food for your dog.

While the feeding trials are being done on your dog, there are some things you, the pet owner, must keep in mind to make the test result viable [5]:• Do not give your dog treats, chewable toys, vitamins, and other chewable medications (e.g. heartworm prevention medicines) that may contain ingredients from your dog’s previous diet.
Give only treats and toys that are made from known safe materials (e.g. apples, vegetables).

• Inform all of your family members of how the test works and what must be done to keep the test diet clean and free of any other food sources.

• Make sure that your dog’s chewable vitamins and heartworm medications do not contain food substances that trigger allergies.​

What can I do for my dog that has food allergy?

If it has been proven that your dog is indeed suffering from food allergy and the food/ food ingredient he or she is allergic to has been identified, you must avoid giving any food substances that might trigger the clinical signs to return [5].

Some food-hypersensitive dogs, cannot consume any commercial diet because of a reaction to the preservative [2].

Azestfor Homemade diets are tailored to meet your dog’s individual needs, and this means that his diet is free from ingredient(s) that can trigger his food allergy, is nutritionally balanced and nutritionally complete.

Azestfor homemade diets  make sure your dog is itch-free and healthy so you and your dog can spend the best moments together.

You can give your dog home-prepared food, which is specially formulated for your allergic dog [1,2] and nutritionally complete and balanced.

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1. Ettinger, Stephen J and Feldman, Edward C. Textbook of Internal Veterinary Medicine, 7th ed. Elsevier Health Sciences, 2009.
2. Miller, William Howard; Griffin, Craig E.; Campbell, Karen L; and Muller, George H. Muller and Kirk’s Small Animal Dermatology, 7th ed. Elsevier Health Sciences, 2013.
3. “Pruritus.”
4. Thompson, Mary. Off to a good start: A manual for raising your new puppy. Adams Media, 1999.
5. Tilley, Larry Patrick and Smith, Francis W.K. The 5-Minute Veterinary Consult: Canine and Feline, 3rd ed. Lippincott Williams & Wilkins, 2004.
6. White, Stephen D. “Overview of Food Allergy (Adverse Food Reactions).” The Merck Veterinary Manual . May, 2013