Often, cats and dogs develop "food allergies" or "food intolerances" to ingredients found in commercial cat food. The top allergens are commercially processed chicken and corn (very common pet food ingredients), beef (often labeled as "meat by-products" or "meat and bone meal"), wheat, dairy products, and fish (especially for cats). However, an allergy can develop to any protein to which the animal is repeatedly or constantly exposed.
Conventional treatments for food allergies include steroids, hyposensitization, and diet therapy.
• Steroids can be given by time-release injection or in tablets. While steroids may be a good choice initially to help animals feel better, the drugs have many side effects and are not recommended for long-term use.
• Hyposensitization requires knowing precisely what the pet is allergic to. The skin test is the "gold standard," but requires anesthesia. There is also a blood test for allergies (sometimes called a "RAST" test). While both are used for dogs, the test is too inaccurate to be used in cats. So how does the process work? Once identified, the allegenic substance is diluted and given by daily injection.
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• Diet therapy uses "novel" or "hypoallergenic" ingredients not commonly found in pet food. Novel protein sources include venison, rabbit, kangaroo, ostrich, and duck. However, pets that are allergic to chicken may cross-react to eggs, turkey, and other poultry; beef-allergic pets may also react to bison and other ruminant proteins (venison, lamb, and such).
Veterinary hypoallergenic diets are available from some veterinarians, and there are also over-the-counter (OTC) diets that may work. However, one study found that some OTC diets contained allergenic ingredients that weren't listed on the label. A diet trial must be strict and must last 8 to 12 weeks: no cheating, no treats, no exceptions. Just one slip-up could restimulate the allergy, and you'd have to start over from square one.
Holistic treatments for food allergies include homemade diets (processed foods, especially dry foods, are more prone to cause allergies), natural supplements like slippery elm, antioxidants, and omega-3 fatty acids to help the skin heal.
It should also be noted that even pets that are not specifically allergic to something in the food may still do better with a hypoallergenic diet. A simplified diet containing fewer allergens gives the immune system less provocation, allowing inflammation to settle down.
Preventing allergies is much easier than treating them. It's a good strategy to vary the diet by changing proteins at least every three to four months. Homemade and raw foods are less apt to trigger allergies than processed food, particularly dry kibble. Adding digestive enzymes and probiotics to all your pet's food will help with proper digestion and moderate inflammation in the body.