The Cause?

When your pet develops an itch, the first thought on everyone's mind is "fleas". In fact, my personal observation is that pet owners really prefer this to be the issue as there are much quicker resolutions to this with pesticides than the exercise that must be gone through to resolve other causes such as food allergy or intolerance with the elimination diet.

An alternate scenario is that your pet is developing congestion that affects breathing, and this may automatically be labelled in some minds as "asthma". In this second case it may also be seasonal allergies and intolerances, and/or polyps, neither of which will be located in the lungs, which is where usual asthma medication takes effect. Runny eyes and staining around tear ducts is another indication of irritation that is not disease based. I mention this alternate here, as one wants to go through a checklist while starting on the elimination diet, as any other cause is quicker to resolve than a food reaction.

Up to this point in time in our own household, we have encountered food intolerances toward protein and other ingredients on pet food labels, and have also battled seasonal breathing issues and polyps.When it comes to dermatological symptoms, there are a number of very good online sites demonstrating different types of eruptions so that one can identify what is likely to be an allergic reaction to fleas, food, or environment, in order to approach the problem by looking at the most likely sources of irritation to resolve the discomfort for your pet as quickly as possible.

A good review of possible allergy/intolerance causes is found at "Clinical Aspects of Gastrointestinal Food Allergy in Childhood".  A small child has a digestive tract that has similar sensitivities to animals, so the same principles apply as we are not dealing with strict dietary choices here.  Mammals are mammals, and in this article stool samples are the main method of analysis.

The IVIS web site has a plethora of information on toxicology issues that will cause a variety of reactions in your pet.  This could be anything from IBS type, (the food allergies we discuss here), to toxicity from the environment, medications, supplements or lack of a nutrient, and more.  Your veterinarian has access to this information and should be working in partnership with you to find the cause of distress, whether it be itching, paralysis, neuropathy, or any other clinical sign.

Explaining the Elimination Diet

The first object your vet will have is to reduce the discomfort for your pet, and there are a number of different foods created as tools to help with this in that unusual protein sources are used as a single ingredient food that may eliminate the itching, sneezing, scratching type of stress that both you and your pet are under while the allergy or intolerance continues.

Here in Canada, according to the available foods in stores and veterinary offices, it appears that the standard protocol taught in veterinary schools uses what is called an "F&P" diet, meaning fish and potato. Other countries seem to lean toward other unusual protein sources such as rabbit, which I would prefer to see, myself, as fish is not a great source of B vitamins for pets and usually there is a general rule to use no more than 30% fish in a pet diet. Humans can make this up with leafy green vegetables added to their plate, but this is not expected to be found in commercial pet foods, and carnivores are not known for their plate of salad beside their kill in the wild that isn't normally fish for cats and dogs.

Sometimes there is sweet potato on the label of foods designed for elimination feeding, but there is little difference between that and regular potato when it comes to nutritional content for pets. The weakness with this particular combination in my mind is that some pets need to restrict postassium levels, and potato is high in postassium. As I have stated before, though, there is no perfect pet food, and the priority here has to be elimintating the source of irritation.

If the first single protein choice is found to eliminate the irritation which took you and your pet to seek veterinary advice, this is the first step in recovery, and you are lucky. Usually, if it doesn't work, another single protein source is picked, such as lamb, beef, and even grain proteins are resorted to. Most of the time the use of rice, or the better protein source of corn gluten meal will work fine in the short term, but there is the odd time that corn has been found to be a cause as well.

Other possible problems with food allergies may be the additives other than proteins such as guar gum, (diarrhea), dairy, (bad stomach pains and sometimes diarrhea), and so on. This means that for some pet owners there may be a long tedious process that will require a lot of patience on your part as your animal remains in discomfort for a longer period of time.

The allergy may have to do with how the source of protein was grown, or processed. This may involve growth hormones, as used to be common in North America when raising poultry, (now banned here), or it could be in a chemical used in the processing of vegetable matter such as the use of sulphites.

This is just the beginning of the journey to resolution of your pet's food issues. There are a number of other items on the ingredient list that may be found to be the irritant for a pet's problems from dermatitis, to asthma, to seizures, IBS and other indications of toxic reaction. Some good general sources of information can be found at the following sites:
Drs Foster & Smith: Peteducation.com has an article called "Food Allergies and Food Intolerance" with the guidelines for feeding an elimination diet about half way down the page.
Laboklin Aktuell has a pdf file you can download with a slightly different perspective on food irritants at a site labelled, "Adverse food reactions in dogs and cats"
There is another point of view at "Food Allergy In Cats: Symptoms, Treatments And Diagnosis" but that site doesn't go into as much detail regarding how to handle an elimination diet.

There are more sites online that refer to food intolerances, but one problem I am finding with even the latest site listed last above, is that alternate triggers are not being addressed. Some of the triggers can involve sulphites or MSG that can be a by-product of protein production.

While coloring and flavoring agents can be among the worst triggers, (look at the struggle around pinpointing ADHD triggers), along with being neurotoxins or exitotoxins, I found it harder to find online information on these for pet foods. However, eHealthMD offers a good overview of a variety of triggers as mentioned above from a human perspective, and colorings are listed at Allergicchild.com under the page "Food Dye Intolerance and Allergy". The yellows and reds are possible triggers for your pet.   Another chemical to look for in ingredients you see listed fits into this "dye" category as tannins are also dyes.  Some sources are listed if you click here and a site that may help you understand why the body can't accept tannins is here.

A book that is available, which might help identify reasons for your pet to have IBS, for instance, is "Digestion, Diet, and Disease" The red color often identified as "E128" is often a major issue for humans, and should be considered so for our pets. Tartrazine, (Yellow #5), can possibly be triggering your pet's asthma, as another example. The action of dyes in the body are sometimes used as a medical tool.

I often wonder why these are not addressed when websites discuss allergies and intolernaces in our pets. Another symptom that is becoming all too common among companion animals is seizure activity. Keep in mind here that the fact that these dyes were found to be triggers came from testing them on animals and getting the same results so the information should not be deemed invalid because it comes from a human focused website.

While I don't personally consider corn to be a threat in our diets, there is the odd anecdotal information out there that does suggest some people/pets do have a problem, and if that is the case you definitely want to look at the list of ingredients that may be generated from corn if you are running out of options when trying to detect an allergen.

Food Choices to Try

I am hoping that readers can add choices for newly diagnosed cases of food related intolerances, as we all know how hard it is to find good foods out there.  Our only experience with this has been related to beef products in cats where they have developed diarrhea, (probably from the unfamiliar fat content), so we have had to avoid beef.  Then, as a total turnaround we have had to avoid all poultry for our foster dog, "Harley" who gets the worst itchy hot spots if given food that contains "chicken" in any form on the ingredient list -- just wish we could get that through to his original owner who insists on feeding him 'treats' with "chicken" in the ingredient list every time they have some quality time together.  It is so hard to help Harley recover from that nasty itchy skin as a result.

For Harley, the only safe food we have found that keeps him happy and healthy is the veterinary Eukanuba /Iams product for Sensitive Skin.  This was to avoid the "chicken fat" or "poultry fat" often found on foods otherwise not containing poultry.  This product listed "animal" fat.

As mentioned at the top of this blog, the human guidelines put out by the National Institute of Allergy and Infectious Diseases can be found if you click on the hypertext in this line.

Please feel free to add comments at the two sections, either under cats or dogs, at the top of the page.