Now what do I feed? Identifying food hypersensitivity in dogs and cats
Food hypersensitivity, food intolerance and other adverse reactions to food (ARF) cause a myriad of effects on several different systems of the body, with the integument and digestive systems being most commonly affected. This two-part article series provides insight into how ARF affects the skin in dogs and cats and how to definitely diagnose and manage patients with food allergies.
Most common culprits
One common misconception of clients and many veterinarians is that food allergy is more likely to develop only after a recent diet change. In fact, when food allergies develop, the offending allergen has often been fed for more than two years, and some patients will eat the same protein for many years before the allergy develops.
Further complicating the workup of a patient with a suspected food allergy is the recognition that some patients will have cross reactions between related food ingredients. This phenomenon is well recognized in human medicine as well. Examples include patients allergic to chicken who will not tolerate duck or turkey. Some patients allergic to beef will cross-react or show clinical signs when exposed to other ruminants, such as lamb or venison. Fortunately, not all patients with food allergies will have cross reactions, but some will.