Diet & nutrition

Could my dog have a food allergy?

Date created: 17 11 2017

Humans aren’t the only ones who can be hit by allergies. In fact, it’s thought that around 10%  of the doggy population is affected by allergies to food, with symptoms ranging from itchy skin to severe digestive and respiratory issues. So does your pooch have an allergy problem?

Why do dogs get food allergies?
An allergic reaction happens when your dog’s immune system responds in a certain way to a particular food. It mistakenly thinks that food is a “foreign invader”, releasing antibodies to attack it - and it’s these antibodies that are responsible for what can be very distressing and harmful symptoms.

When it’s working properly, your dog’s gastrointestinal system is a well-oiled machine. So when their dinner reaches the stomach, it’s broken down into smaller pieces. It then moves into the small intestine, where proteins are broken down into amino acids and absorbed into the body. At the same time, the dog’s immune cells will stop harmful bodies from being absorbed, while allowing nutrients to pass through.

In some cases, the immune cells will mistakenly respond to a non-harmful protein, resulting in an over-response (immune hypersensitivity). That response usually gets stronger over time, which means that each time your dog eats the type of food that’s caused the initial reaction, the allergic symptoms become stronger.


What are the symptoms?
Inflammation of the skin is one of the most common signs. If your buddy’s itching and scratching more than usual, shaking their head a lot, licking their feet or rubbing their body against furniture or the carpet, it’s a sign that they’re in distress - and it could be down to an allergy.

Especially if the inflammation is in areas where the skin is exposed (like the ears), excessive scratching can very easily lead to skin breakage, allowing infection to set in. So especially where a dog is affected by recurrent ear infections, a vet will need to rule out whether an allergy is the underlying cause.

Nausea, vomiting, loss of appetite, chronic diarrhoea, heavy breathing, coughing wheezing, sneezing and lethargy can also be symptoms of an allergy.

Which foods trigger allergies?
In theory, a dog can develop an allergy to any type of food - and the problem can arise for the first time at any age. That said, some foods tend to be more problematic for dogs than others. Pork, beef, dairy, wheat and soy are especially common culprits.

If a dog is allergic to one particular type of food ingredient, there’s a stronger likelihood that they will develop similar reactions to other ingredients, too.

Are certain breeds more prone to allergies?
While any dog can develop an allergy, there’s some evidence to suggest that certain breeds are more prone to them than others. These include Cocker Spaniels, Springer Spaniels, German Shepherds, Dachshunds and West Highland Terriers.

Regardless of breed, it’s thought that if the digestive system is compromised in some way, it becomes more likely that a dog will develop an allergic reaction. So if a dog picks up a gastrointestinal virus, infection or has to undergo surgery, it’s even more important to look out for allergies - even if there has been no problems in this area in the past.

How are allergies treated?
First off; an allergy can’t be “cured” - and nor is it likely that your dog will grow out of it. Once a pet is allergic to something, they’re almost certainly going to always have a negative reaction. So treatment involves identifying what’s causing the reaction - and ditching it for good!

Secondly, take another look at that list of common allergy symptoms. While each of them could indicate an allergy, there are a lot of other health and environmental issues that might be behind them. Itching and inflammation might be down to a flea infestation, for instance. And as for gastrointestinal and respiratory symptoms, these could potentially be down to any number of causes, from viruses and parasites through to chronic genetic conditions.

So if something’s amiss, don’t automatically blame the diet. Book in a consultation with your vet, who’ll take a full history, carry out an examination and find out whether an allergic reaction is the most likely cause.

Depending on how that reaction is making itself obvious, the first step could involve medication to bring the physical symptoms under control (anti-inflammatory treatment to reduce the immediate skin irritation, for instance). Then comes the detective work: identifying the ingredient behind the reaction so you can remove it.

Management of this tends to involve an elimination trial diet; often referred to as a novel-ingredient diet. On advice from the vet, you take two foods that your pet was not previously eating as part of their usual diet (i.e. a meat and a veggie that they haven’t had before). If the allergic symptoms disappear with this “novel” diet, you can assume that it was something in the old diet that was triggering the problem.

So little by little, you can then introduce more items into that diet - including items that your dog was eating in the past. If there are no issues with a particular ingredient, you can keep it in there. But if a reaction is triggered, it’s easy to identify which ingredient led to it - and you can eliminate it easily from your doggy dinner list.

So having gone back to scratch with two basic ingredients, you can gradually build up a new menu with the offending items removed. It takes a little patience - and you need to consult closely with your vet to make sure your dog continues to get the nutrients they require. But the end result should be getting rid of those nasties from the diet - and a happier, healthier dog.