Causes of Canine Food Allergies
Canine allergies of any sort, including allergies to ingredients in food, are caused by an abnormally strong response by the immune system to something that the dog has come into contact with more than once, either by ingestion (eating it), touch, smell or inhalation. The things that trigger allergic reactions are called allergens. In a nutshell, when the immune system perceives something as being foreign and therefore potentially dangerous, it initiates a cascade of events on a cellular level designed to identify and get rid of the intruder. Certain immune cells develop a finely-tuned memory of the foreign substance. When the dog comes into contact with that substance a second time, the memory cells are primed to react faster than they did the first time. Subsequent exposures to the allergen make the immune system’s reaction increasingly sensitive, specific and swift. This is why allergies are also referred to as hypersensitivity reactions.
Different allergens can trigger different allergic reactions in different dogs. Any of the components of dog food, whether commercial or homemade, canned or in kibble form, can cause an allergic reaction. Some of the food products that commonly cause allergies in domestic dogs are beef, pork, fish, lamb, chicken, milk and dairy products, wheat and grains, potatoes, eggs, soy products and a variety of different dietary supplements. Poorly digestible dietary proteins are also common causes of canine food allergies. It can take a long time and a great deal of patience to identify the precise food ingredient or ingredients that are causing the symptoms in a dog with food allergies. Nonetheless, the process is worthwhile and almost always successful.
The most effective way to determine the cause of a dog’s allergic reaction to something in its diet is to put it on what is called an “elimination diet.” This involves taking away the dog’s access to any food products other than one or two specific bland ingredients, such as boiled rice and chicken, and then gradually introducing other ingredients to the diet one at a time. Over the course of the elimination diet, the owner and veterinarian will track the dog’s reaction, if any, to each new ingredient. Hopefully, the ingredient or ingredients that were causing the allergic reaction will eventually be identified.
Preventing Food Allergies
Once specific food allergens are identified, the dog’s owner will need to carefully manage the dog’s diet, to be sure that those offending ingredients are not included in its food. Fortunately, there are a number of high quality commercial diets that contain novel protein sources, such as venison, bison, rabbit, duck and salmon. These often work very well for dogs with allergies to the more common components of commercial canine kibbles, which usually are chicken, beef or lamb. Tasty kibbles with one or more novel proteins are becoming increasingly available at retail pet food outlets. They can really help dogs that are suffering from food allergies regain and maintain their good quality of life.