How to Do an Elimination Diet Trial for Your Pet

Itching and skin issues are not unusual in either dogs or cats. When they become chronic, it’s time to find out what the cause or causes could be.

Sometimes there might be an allergic reaction to a certain type of food going on. It’s possible that there’s a secondary parasitic problem as well. Getting to the bottom of all potential issues is tricky territory but well worth the perseverance.

Arm yourself with plenty of patience as we show you how to do a elimination diet trial for your pet.

Aims and the Importance of Being Strict

The goals of an elimination diet or food trial are these:

  • To confirm whether symptoms are totally or partially due to a particular food
  • To identify ingredients that trigger the symptoms along with those that are safe

Any food trial you carry out needs the strictest of control. One slip and you may as well tear up the trial and go back to the drawing board.

Your pet must eat nothing except the food chosen for the trial-  even the tiniest quantities of uncontrolled ingredients could trigger a reaction and ruin the trial. Imagine a person trying to discover if they’re allergic to peanuts – so they eat only foods that are known to not contain peanuts. If that person is sneakily eating a spoonful of peanut butter every night in addition to their prescribed food, the trial becomes useless!

Making Your Plan

Before you embark on an elimination diet or food trial, here is your to-do list:

  • Talk to family, neighbors and friends and explain the trial
  • Impress on them not to feed your pet anything at all
  • Avoid treats, supplements, flavored medications and toothpaste
  • Double-check with your vet about any “extra” products you’re unsure about
  • Only put out plain water to drink during the trial
  • Buy enough food for the trial so there’s no chance you’ll run out

If the pet having the problem is a cat and if you have more than one of them, you have several options:

  • Stick to strict feeding times
  • Use microchip-controlled feeders to ensure the cat does not get any other food
  • Easiest of all, feed all the cats the trial diet if that’s an appropriate way forward – most elimination diets are completely balanced and so are fine for a normal animal to eat as well.

An issue with outdoor cats is their instinct to scavenge for food or even to tuck into a neighbor’s cat bowl. For purposes of the trial, you may have to keep the cat indoors – as if the cat is eating other foods outside then the trial certainly is not worth doing.

This is especially true because you might discover that the cause of the allergy is something that your cat’s eating when they’re outside the home. Using a “do not feed me” collar is a possibility but clearly not foolproof.

Likely Causes of a Food Allergy

Unlike in humans, there can be a delay in an allergic reaction to a food ingredient. This could be anything from a few days to several weeks. Itching and skin infections often (but certainly not always) come with digestive signs such as vomiting and diarrhea.

Negative reactions to dairy products, chicken, beef, and wheat make up over 75 percent of all reported cases in dogs. Negative reactions to eggs, chicken, soy, lamb, fish and corn are far less frequent, while reactions to rice and duck rare.

In cats, negative reactions to dairy products, chicken, eggs, beef, and fish make up more than 90 percent of all reported cases. There is no evidence of dogs experiencing allergies to naturally-occurring peanuts and other kinds of nuts.

What Foods Should I Use for My Food Trial?

There are 4 main categories of dietary options for the trial. We often refer to the first two diets as hypoallergenic diets. Here are the 4 choices:

1. Novel Protein Diets

The focus of this is to use a commercial food to provide kinds of protein that your pet has never had before, the logic being they cannot be allergic to food they haven’t ever eaten. Examples include rabbit, goat, or deer. The source of carbohydrates might be new too, for example, potato rather than rice.

2. Limited Ingredients Diets

The aim here is to offer only one kind of animal protein in the diet that your pet has never eaten. The food could be either a commercial brand or home-cooked. Most experts would recommend a commercial variety as they tend to have better nutritional balance.

3. Hydrolyzed Protein Diets

These are different from both of the above because the proteins in them go through a process known as hydrolysis. This breaks them down into such small fragments that the immune cells cannot detect making them impossible to react to.

These foods will always be commercial. It doesn’t matter what the source of the protein is because hydrolysis makes them all unrecognizable to the gut’s immune cells. There are very effective, high-quality, and nutritious commercial hydrolyzed diets available, and so this option is often the easiest as you don’t need to worry about what foods your animal might have been exposed to in the past.

4. Homemade Diets

It is of course possible to make your own elimination trial food for your pet, but this can be time-consuming to prepare and it can be tricky to get the nutritional balance right. You should always talk to your vet before embarking on this option.

Speak to Your Vet Before Making Your Choice

Your vet will help you choose the most appropriate food based on your pet’s medical history, age, symptoms, and home situation.

Hydrolyzed products tend to be less tasty and more costly when compared to hypoallergenic foods. It’s possible your vet will recommend a hydrolyzed protein diet but weigh up using a hypoallergenic food should your pet refuse to eat the hydrolyzed protein diet. A hydrolyzed diet offers a simpler opportunity to add in and test other ingredients during the trial.

The hydrolyzed protein diet won’t trigger any allergic reactions while the other diets may still throw up evidence of ingredients that your pet has an allergy to.

The Food Trial

A food trial typically has 3 or 4 stages. Here’s a brief rundown of each:

Stage 1

You should stick strictly to the new selected dietary regime for 6 to 8 weeks. Do not give your pet anything except this food along with water. Keep a daily record of your pet’s symptoms. These could include:

  • Instances of vomiting and diarrhea or itchiness levels and rashes

Some pets can be particular about their food and you should incrementally mix in the new food with the old over a period of days in order to avoid gastrointestinal upset. Start the trial timer (usually 6-8 weeks) from the day your pet only eats the new food.

Your pet may have been experiencing severe symptoms that needed anti-inflammatory or antibiotic medication before the trial. If so, start the trial once the effects of the medication have passed. Your vet will be able to advise you.

Stage 2

Once Stage 1 is complete, re-introduce small quantities of the old foods as well as your pet’s usual treats or supplements over a period of about 2 weeks. Keep a close eye on whether the symptoms return.

If the symptoms were due to a food allergy, they’d be likely to reappear up to 2 weeks afterward.

Only give very small quantities of the old foods or treats. Any sudden changes could cause a stomach upset.

Stage 3

If any of the adverse symptoms come back, revert to strictly feeding your pet the new diet until they’re gone again. This will typically take between 2 and 4 weeks.

Moving on to the Possibility of Stage 4

If your pet makes a big improvement during Stages 1 to 3, you have 2 options:

  1. Embark on no further food challenges. If the new diet is complete and if your pet appears happy with it, carry on feeding it to them for life. Most commercial foods are fine to feed a healthy animal for life. Although an acceptable solution, you still won’t know what precisely your pet is allergic to.
  2. Move on to Stage 4 to find out the specific ingredients that cause your pet’s symptoms.

Stage 4

Continue to feed your pet their new diet but offer them ingredients from their previous food or treats on their own. For example, if their old food was chicken-based, feed them small pieces of plainly cooked chicken.

Only offer one new ingredient at a time and for up to 2 weeks. Be on the lookout for the return of adverse symptoms. If everything’s fine, you can add the ingredient to your “safe foods” list.

If there’s a return of any adverse symptoms, you’ll know to avoid that ingredient and to only feed your pet the new food again until the symptoms are gone. Do not begin any further challenge until any flare-up has totally gone away.

The proteins in beef, eggs, chicken and dairy products tend to be some of the most common triggers. You should initially work your way through these. Check the ingredients listed on all your pet’s old foods for any indication about which ingredients might act as triggers.

Your goal should be to end up with a choice of complete diets you can use in the long-term that your pet enjoys and that do not trigger any skin or gastrointestinal issues. Just like in humans, food allergies can be very complex and not straightforward. So – generally – once you find a specific food brand that works for your specific pet – just stick to that!

Talk to a Qualified and Experienced Vet

There are clear links between allergies, nutrition and dietary balance. It’s crucial that you have the opportunity to talk to a vet during the whole elimination diet trial process.

If you’re planning a food diet, do get in touch with us now. We will always have an experienced vet available to help. Find out more information about all our competitively priced pet insurance products too.

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