Vet discusses novel protein diets for cats to manage allergies

In this second part of an email conversation with a friend, Dr. Michael Watts, companion animal general practitioner and owner of Clevengers Corner Veterinary Care, shares his advice on pet nutrition and why prescription petfood diets do work for managing a pet's health problem. 
Dr. Watts says that many niche diets, as opposed to prescription diets, are made to balance according to textbook nutritional values, but many niche diets do not do animal feeding trials to measure the actual nutrition performance, with the exception of a few organic brands. Dr. Watts says that when choosing a food, pet owners should look at the food’s Association of American Feed Control Officials' statement for the words "animal feeding tests substantiate this food is complete and balanced." If the words "animal feeding tests" are missing, the tests haven’t been done, he says.
Finding a food to manage a pet's allergy may take time, Dr. Watts says. He says a true novel protein diet may take up to eight weeks to see a response. 
"It is difficult to find a truly novel protein for cats because ordinary cat foods contain so many similar flavors and ingredients," Dr. Watts says. "Duck, for instance, often cross reacts with turkey and chicken. Beef often cross reacts with venison, bison, etc. Add to that the difficulty that many OTC formulas that say 'soy free' or 'grain free' have been shown to have significant enough levels of these ingredients to aggravate a truly allergic cat. It’s not so much they’re 'sneaking it in' as there is inadvertent contamination. Feed mills are dusty places and it’s easy to have cross contamination of production lots."
While the dog food market has a few truly novel protein diets, using ingredients like kangaroo or rabbit, very few over-the-counter diets for cats have these novel proteins; most are limited to salmon, chicken, duck and venison. Dr. Watts says that these cat diets are not totally novel for all cats, so it may be easier for a vet to find a prescription hydrolyzed protein diet, which breaks down the protein into small enough units that the cat's immune system, theoretically, does not detect it. 

Dr. Watts recommends the website, balanceit.com, for pet owners looking for a novel protein diet but who do not want to feed a prescription diet. The site sells supplements that make a homemade diet complete and balanced on paper and were formulated by board-certified veterinary nutritionists. This allows cat owners, especially, to select their own novel protein source and use the supplement to make the food balanced for the cat's nutritional needs. 
"Also, you should know that many food allergic cats also have some degree of gastrointestinal involvement. They are also much less likely than dogs to manifest food allergies as solely skin symptoms. Since you mention only skin symptoms, be sure your veterinarian has thoroughly explored all the dermatologic angles and has run general blood work before placing too many eggs in the food allergy basket," Dr. Watts advises.