Food Allergies Common in Dogs
A food allergy by definition is an abnormal reaction to an ingested food or a food additive, which is often a protein source. Actual food allergies are responsible for ten to twenty percent of allergic (adverse) skin diseases in dogs and cats and adverse skin reactions are less common in dogs than in cats. Food allergies are the third most common allergic skin disease in dogs and cats after Flea Allergy Dermatitis and Inhalant Allergies.
Beef, dairy and wheat are the ingredients incriminated in 68 percent of dogs with allergic skin disease. Adverse reactions to chicken, chicken eggs, lamb and soy are responsible in approximately 25 percent of canine cases. Corn and food additives are occasionally significant.
Up to 1/3 of dogs with skin disease due to food allergies are less than a year old. All breeds are susceptible, but those at increased risk include:
* Cocker Spaniels
* Springer Spaniels
* Labrador Retrievers
* Miniature Schnauzers, and
* West Highland White Terriers.
(NOTE: German Shepards and Chinese Sharpeis are two breeds that, like most people, get diarrhea instead of skin disease as the result of food allergies.)
(NOTE: Dogs with milk intolerance generally experience diarrhea, bloating and abdominal pain. The intolerance is actually an inability to digest the milk protein “Lactose”.)
The most common sign is year-round itching. Dogs classically lick and rub their face, fee, armpits and groin. A copper colored discoloration often occurs as a result of the constant licking and is a prominent sign in certain white-coated breeds, i.e. the West Highland Terrier.
WHAT YOU AND YOUR VET CAN DO
The dog’s nutritional history should include a complete list of commercial and homemade foods as well as snacks, treats, chew toys, chewable medications, and human foods.
1. The only way to find out the true cause of a food allergy is to use an elimination diet. A single source of protein is used for 12 weeks to see if the dog’s condition improves. Then new ingredients are added back into the diet one at a time, every five to seven days, until the problem recurs.
Using this method, and noting what was added when, if there is a reaction you will know which food ingredient is responsible for the problem.
2. For the elimination diet to work, start by using a protein source the dog has not been previously exposed to like lamb, fish, rabbit, venison or tofu.
3. The protein should be highly digestible (over 87 percent digestibility).
4. Avoid food with over 30-45 percent protein in skin cases only.
5. Use foods with no or few additives.
6. Ingredients recommended for homemade canine diets that work best initially for dogs include one protein source or a combination of one protein and one carbohydrate source. For example:
* Lamb baby food
* Rice and rabbit
7. Use distilled water or boil tap water and refrigerate – this helps avoid chlorine, which can be a factor.
8. If diarrhea is present, avoid foods with wheat, barley, or rye.
Food allergies tend to be lifelong but once you identify the offending allergen, you can find a variety of suitable diets that don’t include the problem foods but still provide a balanced diet. Your vet can suggest appropriate “allergen” free diets you can make at home or buy. Keep a daily diary during the elimination phase to keep track of the type of food eaten and any signs that occurred as a result.
If a food allergy is the only cause of the problem, itching should stop and signs should improve 100 percent. Up to 1/3 of dogs and cats with food allergies also have other allergies and therefore, may only respond partially to an elimination diet. Flea Allergy Dermatitis and Inhalant Allergies are the most common causes and should be ruled out through other testing.
Vitamin C in high doses acts as an antihistamine and may help with itching, if present. A daily dosage up to 1,000 mg is recommended. Adding Vitamin B complex to the daily diet is also useful. Give the dog a quarter to one tablet each day.
(NOTE: Vitamin dosage will vary depending on body weight.)