Let’s dispel some food and allergy myths
I had the pleasure of listening to Dr. Simon Quek BSc. BVMS MRCVS. at the Pet Expo recently. He was there to give a talk on Environmental and Food Allergies for Dogs. I am also privileged to be able to consult with Dr Joanna Paul, a small animal veterinarian in Melbourne, Australia. She runs the blog – Creature Clinic. ;)
This post is a result of talking to both of them :)
This post covers the following points on Dog Allergy:
- Not all dogs are allergic, haha!
- For those dogs that are allergic,
- Flea bites and Environmental (inhaled) allergy are more common than food allergy in dogs.
- Food allergies account for only 10‐15% of all the allergies seen in dogs.
- Food allergy can absolutely result in skin reactions without any risk of death.
- For the 10-15% food allergy cases, most food allergy are due to beef, dairy or wheat.
- This is followed by chicken, chicken eggs, lamb and soy – about 25% of food allergies in dogs.
- The Elimination Diet Trial is the only sure way of assessing a pet’s allergy towards particular food.
- The Bioresonance test is unproven and not science-based. Use is not advised.
- Detailed exploration of how the Elimination Diet Trial is conducted
- Why the chicken crossed the road. :P
But first, is your dog really allergic?
As the human of a dog that I adopted more than 2 years back, sitting in on a professional discussion from trained vet professionals is of course, way overdue. To my defence, I plead Donna’s hybrid vigour as my reason for not needing education in this topic sooner. Hah!
But attending the Pet Expo seminar was timely because Donna had been nibbling the side of her bum, until the hair there has been nibbled short, and it’s starting to look sparse. The patch a blatant accusation that I don’t take good care of my dog. OMG!
So after his talk, I hung around waiting to ask Dr. Quek specific questions about Donna. Now, during the whole talk Donna had plonked herself right in the middle of the aisle in front of the vet, scratching and scratching away.
But Dr Quek looked at her and said that her scratching was probably not due to an allergy.
He explained that a dog needs to display more than a couple of the following symptoms in combination in order for her to be possibly suffering from an allergy. List may not be exhaustive.
- redness about the eyes
- rashes under the arms
- itchy ears, shaking head
- paw licking, in between toes and digits.
In Donna’s case, her coat is healthy, and the fur in her ears are full. No signs of skin inflammation or persistent scratching there. So really, it’s only at the side of her bum area and some small rash around her lower tummy/groin, which the vet suggested may be due to insect bite. Hah!
But there are exception cases, says Dr Jo.
“I’ve seen many dogs with itchy skin that are non-lesional. i.e. you can’t see anything wrong at all just looking at it, but it’s still very itchy. I would say the vast majority of these have been atopic dogs …(that react to allergens in the environment) and I’m not sure any have been diagnosed with food allergies specifically.”
But what if your dog is really allergic?
Dogs who itch, lick, chew, rub, bite, and scratch themselves year round, typically around the face, ears, armpits, groin, paws, and around the anus may be showing signs of a food allergy. Since itchy flare factors have an additive effect, it is important to eliminate other possible causes of itching. – vetmed.tamu.edu
It’s easy to blame it on the food. Every few months I have some relative or other telling me I need to change Donna’s food because she sheds. And yet, they themselves don’t have a dog(s) and they don’t even know what I am feeding Donna with. But like what Dr Jo advised, the cause of the scratching could be environmental.
So how exactly do we know if the dog is allergic to food? Or to something else? Or not at all?
Well, there are tests the vets can do. And tests that do not require the vet. In his talk, Dr Quek went on to describe these various ways of testing for allergies.
- Serum testing/ blood test
- not accurate, high percentage of false positive results
- Intradermal skin testing
- for environmental allergies only
- Patch testing
- positive results are not true positive but negative results are true negative, so it’s useful for elimination diet trials
- Skin Biopsy
- only indicative of allergy but does not differentiate between environmental or food allergies
- no scientific basis behind it. Not approved for use in human medicine.
Wow, all these tests just seem to be a waste of time and money. At best, the skin biopsy confirms the dog is allergic to something. And the patch test confirms what the dog is NOT allergic to.
So exactly what works?
Bring on the Elimination Diet Trial
You can do this with a vet. This AsiaOne article quoted Dr Quek who estimated that a diet trial can “cost $150 a month for a 5 to 10kg dog”.
But the concept is really quite simple, so you could also try it out on your own, said Dr Quek in our conversation. (Note: His comment is on the premise that just taking a healthy dog off his regular diet for a short period of time is not going to affect his health adversely, as long as he goes back to a complete and balanced diet after that. But if the dog’s diet trial is going to be prolonged, it is advisable to work with a vet/nutritionist to ensure the dog is getting all the nutrients essential to his health and well-being.)
Basically, what you need to do is to transition the dog to a simple diet comprising, one novel protein source and one carbohydrate (gluten-free). Possible combinations include:
- goat and sweet potato or pumpkin
- frog and sweet potato or pumpkin
- crocodile meat and sweet potato or pumpkin
- rabbit and sweet potato or pumpkin
- venison and sweet potato or pumpkin
Note that “Novel” means that your dog has not eaten it before.
The point here is to take the dog’s current food, which may be causing the scratching, out of the picture. You do this by replacing it with a protein that the dog has never eaten/been exposed to before and hence has not develop an allergy towards.
In Donna’s case, that means rabbit and venison are already struck off the list since she has eaten commercial food containing these before. *Oops!*
The key challenge here is to be really strict about making sure the dog eats ONLY that one combination of food for a minimum eight weeks long, according to Dr Quek. That means, if I were to do this with Donna, she would only have e.g. frog and sweet potato for all her meals. No treats, no other food.
Veterinarians used to recommend that a pet only needed to be placed on a special diet for 3 weeks but new studies show that in dogs, only 26% of those with food allergies responded by day 21. However, the vast majority of pets responded by 12 weeks. Therefore, it is very important to keep the pet on the diet for the entire 12 weeks. – citations on their webpage
Wow, this is really hard!! But it’s the only way.
And I’m not the only one who thinks so. I have gotten a couple of comments on Facebook from people who advised or they, themselves preferred to go for the Bioresonance test instead of the Elimination Diet Trial because it is “cheaper and faster in the long run.”
But both Dr Quek and Dr Jo are in agreement that the Elimination Diet Trial is the only sure way of assessing a pet’s allergy towards particular food.
In fact, Dr Jo hadn’t even heard of the Bioresonance Test before in Australia!
She kindly did some research for me but says,
I couldn’t find any reputable sources of info specifically about bioresonance, but here are a couple of abstracts from articles that don’t recommend it… It seems that it is not evidence based, and there is no science to suggest it is useful.
And while it is difficult, the elimination diet trial is at least science-based, accurate and supported by vets.
For some pets, it doesn’t have to take all twelve weeks
Dr Jo’s recommendation?
That (being on a strict one protein and one carbohydrate diet for twelve weeks) is very, very commonly recommended, but honestly, you should be seeing some improvement in the first month. If the pet responds the next step is to introduce one potential allergen at a time, for two weeks, and to allow a one week washout period in between each.
So at least there is some hope there. Haha :P
Drawing conclusions from the first elimination diet trial dog undergoes
After the food trial period, if the dog is still scratching and does not get better, it means food is not the factor in causing the scratching. If the dog is allergic, then the dog may be allergic to environmental allergens instead. In fact, food allergy in dogs is not as common as environmental allergies or flea bite allergies.
Food allergies account for about 10‐15% of all the allergies seen in dogs and about 40% of all allergies seen in cats. It is the third most common allergy after flea bite allergies and atopy (inhaled allergies). – Rocky Mountain Veterinary Dermatology, Inc
But really, it is less likely to be the food
There are some breeds that are more likely to have specific dietary intolerances, but I’m not seeing anything increasing in frequency in my practice. In my experience, food allergies causing itching is really uncommon (I would say definitely less than 10% of itchy dogs in my location).
We are much more likely to see dogs with chronic gastrointestinal problems (like inflammatory bowel disease) that relate to dietary… intolerance than skin manifestations. – Dr Jo, via email
So yup, let’s not be quick to blame itchiness on the food. In fact, I know Donna tends to scratch more and do these throwing up noises more often if she had been on the balcony, because we have a construction site in front of us. Our vet advises that it’s probably environmental allergies.
Conversely, if the dog stopped scratching after being on the limited one protein and one carbohydrate diet, then it is highly likely that the food prior is the source of his allergies.
If the dog shows a marked reduction or elimination of the symptoms, then the animal is placed back on the original food. This is called ‘provocative testing’ and is essential to confirm the diagnosis. If the symptoms return after going back on the original diet, the diagnosis of a food allergy is confirmed. If there has been no change in symptoms but a food allergy is still strongly suspected, then another food trial using a different novel food source could be tried. – petducation.com
But if it really is the food, it must be the chicken?
Chicken has a bad rep when it comes to food allergies.
A quick check with dog treat seller The Barkery Singapore confirms this:
Many of our customers do tend to avoid chicken even if their dogs are not allergic just to be safe. Chicken has a really bad rep as far as we know. But we also do have customers who are happy to give their dogs chicken because it’s very digestible… Many food allergies are caused by bacterial imbalances in the gut. Once gut imbalances are addressed, the symptoms of allergies are likely to subside.
The Barkery has been selling yummies for dogs for almost 4 years in Singapore, so it is interesting to get their observations of the dog food scene locally.
So imagine my surprise while reading the book Dog Food Logic, to find the author and nutritionist Linda P. Case point out that research showed that dogs with food allergies were found to be most allergic to beef and dairy products, not chicken! :P Chicken follows after beef and dairy products if I am not wrong.
Buy this interesting read on Amazon :P
So don’t blame the food and don’t blame the chicken
Well, not until you put your dog on an elimination food trial anyway. :P
Why did the chicken cross the road?
To escape the blame, of course! :P
See also All other posts on Dog Food by weliveinaflat ;)
This post is written collaboratively with advice from our vet partner, the lovely Dr Joanna Paul. She writes at Creature Clinc [ creatureclinic.com ]. I’m very happy and privileged to be able to tap on her expertise on subjects to do with pet health & medicine! :) Articles with her input are tagged “creature-clinic” for easy reference.
I also recommend her recent article Heartworm Disease in Dogs – And the epic tale of a worm named Laverne over at creatureclinic.com. it’s easy reading and gave me a better understanding of heartworm disease and why preventatives are important. ;P
Weliveinaflat is also grateful to:
- Dr. Simon Quek BSc. BVMS MRCVS for taking the time to chat. The talk at Pet Expo was definitely helpful and interesting.
- The Barkery Singapore for answering our questions about customer protein preferences.
- Everybody else on Facebook for responding to my query!