Rice allergies are relatively common in dogs. Some veterinarians believe a reaction is triggered over time by exposure to rice, an ingredient found in many dog foods and treats. Rice allergies may be diagnosed by blood testing, intradermal skin tests or an elimination diet. A dog allergic to rice should avoid ingesting rice products and instead eat a food containing a different carbohydrate source.
Symptoms
Symptoms of a rice allergy may include itching and hair loss when a food containing rice is consumed. Redness and irritation of the skin may also be observed. The dog may have "hot spots" that can be felt when stroking his sides, haunches or belly. Hot spots will be noticeably warmer than the rest of the dog's skin. Hot spots aren't always due to food allergies. If a rice allergy is present, a reaction will be observed within 24 hours of the dog consuming a food that contains rice.
Causes
Rice allergies may be caused by exposure to rice throughout the dog's life. At one point, lamb and rice dog food formulas were thought to be ideal for dogs with food allergies. Good results were observed because, when these formulas were first introduced, most pet dogs had not been exposed to lamb and rice. This led to a saturation of the market with supposedly superior, hypoallergenic lamb and rice dog food, which in turn caused many dogs to develop allergies to lamb and rice.
Testing
Rice allergies may be diagnosed through blood testing, intradermal skin testing or an elimination diet. Blood tests are performed using either the RAST or ELISA method. Both require a small amount of blood to be drawn and exposed to allergens. If numerous antibodies are produced when the blood is exposed to a particular allergen, the dog is allergic to that substance. Intradermal skin testing requires sedation and shaving a large area of the dog's side. Small amounts of allergens are then injected into the skin. A raised area of irritation will be observed when an allergic response is triggered. An elimination diet requires feeding the dog a diet with one source of protein and one carbohydrate that are completely new to the dog. After a diet that doesn't cause a reaction has been identified, the owner may add ingredients from the dog's former diet, one at a time. If adding rice back into the diet causes a reaction, the dog has a rice allergy.
Similar Allergies
Dogs with rice allergies may also be allergic to other carbohydrates used in the production of pet food. Dogs allergic specifically to rice gluten are likely to react to other glutens, including corn gluten and wheat gluten. Corn, wheat, soy and chicken are the most common allergens in dogs.
Management
Rice allergies can be managed by feeding a diet that doesn't include rice. Alternate carbohydrate sources may include sweet potato, quinoa or amaranth, among others. Try to rotate the dog's diet while avoiding rice so as not to create new allergies. If you find a dog food brand that your dog does well on, see if it has multiple formulas with different sources of protein and carbohydrates. If so, change formulas within the same brand each time you buy a new bag.