If your dog has food allergies, his immune system is reacting to the food. This is not the same thing as food intolerance, like lactose intolerance. Of all the allergies dogs have, food comes in at number 3, behind flea allergy dermatitis and canine atopy.
Food allergies are not seasonal like canine atopy. Most times, it is a protein in the food that causes the allergy. It is usually animal based, like eggs, meats or dairy, but it could be a carbohydrate as well. A dogs most common allergies include chicken, beef, eggs, fish, milk, horse meat, soy, wheat gluten, corn, potatoes, or additives.
The clinical sign seen the most is extreme itching, chewing, and scratching. There could also be red bumps and infection of the skin involved. Dogs are most affected in the areas of the paws, groin, flank, ears, and neck. They often have recurring ear infections along with the food allergy. Cats normally just scratch their ears and faces and these signs happen year round.
The food allergy can also show up in the gastrointestinal tract, instead of the skin component. Signs of this include; diarrhea; chronic vomiting; belching; loose stools; frequent bowel movement, and/or flatulence.
Since there is no single test for food allergies, talk to your vet about starting an ' elimination diet' that consists of giving your pet highly digestible proteins and carbohydrates, but no food additives. It is advised to choose a protein and carb that your pet has never had before, not even once. These foods include duck, rabbit, kangaroo, snow peas, potatoes, along with a source of fat. The first trial does not need to be balanced.
If your pet`s itching decreases, it will take a crucial period of over 2 months to get the diet adequately balanced. Usually itching will decrease in about 6 weeks but some have seen results in as little as a couple weeks. Nothing extra should be given to the pet while on the trial diet and the pet will do fine as long as he is not re-exposed to the food ingredients that caused the allergy.