Greencross Vets What is a food allergy?
Allergic reactions or food intolerances occur when the pet’s immune system responds to its food, causing an inflammatory reaction. The exact cause is not completely understood, and it is not easy to distinguish between true allergic reactions and food intolerances. Similar reactions can occur in people, such as lactose intolerance and allergies to MSG or other preservatives. Food allergies can develop even when a pet has been fed the same diet for a long period.
What is the incidence of food reactions?
Food reactions are responsible for approximately 10-15% of all allergic skin diseases in dogs and cats. It is the 3rd most common itchy skin disease in dogs and the 2nd most common itchy skin disease in cats.
What are the signs and symptoms?
The symptoms of food allergy are similar to other allergies. Symptoms most commonly include:
- Itchiness – can occur anywhere on the body
- Redness of the skin
- Licking feet
- Ear infections – particularly yeast infections.
Less commonly, we may see:
- Vomiting and/or diarrhoea
- Excessive gas or flatulence.
How do we diagnose food reactions?
A food elimination trial is the definitive test for food allergies. The diet must be restricted to one protein and carbohydrate source – preferably sources the pet has not eaten before.
This new food source must be fed exclusively for up to 13 weeks or three months. For food trials, we use a complete and balanced commercial dry food. The food is very palatable, and most dogs will eat it happily.
Pitfalls of food elimination trials
- Feeding other food: For the food trial to be effective and accurate, it is essential that no other foods are given to your pet. The food trial will involve a change of diet and, in some cases, a change in the feeding routine. This can be one of the hardest things for many pet owners and families to do.
- Not continuing for long enough: The food trial must be continued for at least 13 weeks before we can be sure a food allergy is not the problem.
- Outdoor pets: Must be prevented from accessing other foods during the food trial. This includes digging up buried bones and hunting small animals.
- Treats: We do not allow treats to be fed treats during a food trial.
