How do you know when your dog needs a dog food allergy test? In my family, we learned the hard way.
When I was in elementary school, the neighbours gave us two Great Pyrenees puppies from the same litter, brother and sister. We named them Samson and Delilah. Samson started playing with my two-year-old brother when he was just six weeks old, and Delilah wanted to explore everything all the time.
But when they were about nine months old, our two Great Pyrenees puppies started scratching their ears. They scratched, and scratched, and scratched. My parents at first thought the problem was fleas, but flea treatment didn’t stop the scratching. The idea of doing a dog food allergy test never crossed anyone’s mind.
Then they tried the treatment for ear mites. No success.
Finally, my mother decided to try a chicken and rice diet and forbade us to give them anything else. We didn’t realize that was actually a dog food allergy test. That did the trick. In about three weeks, Samson and Delilah stopped their constant scratching, their bloody ears healed, and they were a delight to our family for many years.
Food allergies don’t cause every skin problem in puppies, and chicken and rice are not a universal diet to treat them. After all, dogs can be allergic to chicken, rice, or both foods. But there are things to look for that tell you it is time to get your puppy a dog food allergy test and ways of getting your growing dog back on track for a healthy, happy, allergy-free life.
Signs It’s Time for a Dog Food Allergy Test
Canine food allergies produce a variety of clinical signs. These clinical signs are all signals it is time for a dog food allergy test,
One of the most common symptoms of food allergies in dogs is itchy ears, as it was for Samson and Delilah. Inflammation of the soft tissue of the external ear and inflammation of the ear canal sets the stage for ear infections that come back over and over again, almost as soon as you treat them.
There may be quite an odour coming from your dog’s ear. You will see a fair amount of black debris. (If the debris is brown or white and seems to move around, it’s more likely to be ear mites.) When the constant irritation caused by food allergy sets up yeast infections, the inside of the external ear (the part you can pet) will probably be red, and the ear will be smelly.
If your dog us a candidate for a dog food allergy test, you might see repeated eye infections. Your dog might develop blepharitis, a condition in which the eyelids generate lots of sticky mucus.
Food allergies can cause the same symptoms as atopy, or environmental allergy. Your dog might lick her paws a lot.
Dogs with food allergies may scratch their groin a lot. Papules and pustules may develop from skin infections that enter the skin when your dog scratches to relieve an allergic itch.
Canine food allergies can also cause perianal irritation, so dogs lick their butts a lot. Overall, food allergies in most dogs cause mostly skin irritation, with lots of secondary problems resulting from constant scratching, biting, and licking to stop the sensation of itching.
Here are some things every pet parent needs to know about food allergies in dogs:
- Food allergy occurs when your dog’s immune system overreacts to some protein in a particular food. A one-time reaction to something your dog should not have eaten is not a food allergy. If your dog has a food allergy, the problem is not some food you just started feeding them in the last two weeks.
- Food allergies can also cause vomiting and diarrhoea. Dogs that react with vomiting and diarrhoea tend not to have skin problems, and dogs that develop skin problems tend not to have vomiting and diarrhoea (at least the kind caused by an allergic reaction to food).
- Food allergies usually show up at about the age of six months. Puppies are never allergic to foods they have never eaten before. Your puppy will develop an immune system response only to foods he eats repeatedly.
Puppies that have had food allergies may just need to “go” to defecate very frequently. They may not develop runny diarrhoea or vomiting. Flatulence, tummy rumbles, straining to defecate, and painful defecation can also be symptoms of food allergies in puppies.
In up to 70 per cent of dogs that have food allergies, the only symptom is itchy ears.
How Do They Test for Food Allergies in Dogs?
It is always best to let your vet determine whether your dog has a food allergy. That is because your veterinarian will rule out other problems, such as kidney disease, fleas, mites, and unusual reactions to flea medication.
In puppies up to six months old, intestinal parasites are often the real problem. And in adolescent dogs up to the age of two years, the problem allergen is more likely to be some chemical around the house than some component of food.
Once your vet is confident the problem is a food allergy, there are reliable tests to identify the food you need to exclude.
RAST Testing
A radioallergosorbent or RAST test is a blood test that identifies specific allergens. Your vet takes a single blood sample and sends it off to a lab for analysis. The report identifies the specific foods or other substances causing allergies in your dog.
The shortcoming of RAST tests is that they often come back with false positives. That is, they say your dog is allergic to foods that are not really a problem. However, dogs that are treated on the basis of RAST testing do better several months later than dogs treated on the basis of other methods.
Scratch Testing
Intradermal testing, or scratch testing, is similar to the allergy tests many people get. A veterinary dermatologist shaves a patch of your dog’s coat and injects tiny amounts of allergy-causing substances. If a whelp or skin inflammation develops, your dog is allergic to that food/
Because scratch testing can be graded by the severity of the skin reaction, it is more accurate than RAST testing. However, it has to be done by a veterinary dermatologist, which may involve travel costs and time away from work.
Elimination Diet
There is one more way of doing food allergy testing for your dog. It’s an elimination diet.
The veterinarian gives you a prescription for hydrolyzed protein to feed your dog for four to eight weeks. Hydrolyzed protein is meat with all the allergy-provoking proteins removed. Your dog’s symptoms should stop. If they don’t, the problem really wasn’t a food allergy.
Once your dog is better, then you start feeding them one entirely new protein, something they have never eaten before in their lives, at a time. New foods will not cause allergies. You can also begin to add back old familiar foods one at a time, every two weeks or so, eliminating them again if allergy symptoms come back.
What Are the Most Common Causes of Food Allergies in Dogs?
Have you been feeding your dog common food allergens? If you have, it may be time for a dog food allergy test.
The most common food allergens in dogs are beef, chicken, egg, dairy, soy, wheat, and corn. If you cannot afford to take your dog to the vet for allergy testing, you can try giving your dog a diet free of all of these foods. If your dog is happy on the new diet, great! But you can also add back old foods one at a time to see if they were really the cause of your dog’s allergy problems.
One Thing to Remember About Dog Food Allergy Testing and Your Dog
Allergy testing won’t work if your dog gets even a tiny amount of the food being tested during a dog food allergy test. Everyone in the family has to understand that your dog cannot have her old dog foods and her old dog treats for a little while until the allergy testing is complete.
