Is it the Chicken?

When we got Bailey, our first stop was to the Pet Store to stock up on the food she was already being fed by the Breeder. It was a national brand dry puppy food (Pedigree) and we felt it best to keep her on the food she was used to. Once we diagnosed the possible food allergy, we took a look at the ingredients in the puppy food . This was a chicken flavored food and I have a Jack Russell Terrier who is allergic to chicken, so we thought that might be the culprit. We head to the grocery store and pick up a bag of Purina One Lamb and Rice puppy food. After a couple of days we notice she is still scratching but not as much as before we changed the food.
I would like to add that both of these are decent Pet Foods, unless you have a dog with food allergies.

Compare the ingredients in the Pedigree Puppy to the Purina One Puppy

Pedigree Puppy Chicken

Ground Whole Corn, Chicken By-product Meal, Rice, Corn Gluten Meal (source of Lutein*), Animal Fat (preserved With BHA And Citric Acid), Ground Whole Wheat, Monocalcium Phosphate, Natural Flavor, Salt, Brewers Dried Yeast, Potassium Chloride, Fish Oil (preserved with Mixed Tocopherols)[source of DHA*], Vegetable Oil (aource of Linoleic Acid), Vitamins (Dl-alpha Tocopherol Acetate [source of Vitamin E], Choline Chloride, L-ascorbyl-2-Polyphosphate [aource of Vitamin C*], Vitamin A Acetate, Thiamine Mononitrate [Vitamin B1], D-calcium Pantothenate, Biotin, Riboflavin Supplement [Vitamin B2], Vitamin D3 Supplement, Vitamin B12 Supplement), Calcium Carbonate, Taurine, Dried Vegetables (Peas, Carrots), Minerals (Zinc Sulfate, Zinc Proteinate, Copper Sulfate, Copper Proteinate, Manganese Proteinate, Potassium Iodide), Marigold Extract, Added FD&C Colors (Yellow 6, Yellow 5, Blue 2), Rosemary Extract.

Purina One Healthy Puppy Lamb and Rice

Lamb, brewers rice, corn gluten meal, oat meal, fish meal (source of DHA), whole grain corn, animal fat preserved with mixed-tocopherols (form of Vitamin E), poultry by-product meal, animal digest, calcium phosphate, potassium chloride, salt, caramel color, calcium carbonate, choline chloride, L-Lysine monohydrochloride, zinc sulfate, Vitamin E supplement, ferrous sulfate, manganese sulfate, niacin, Vitamin A supplement, calcium pantothenate, thiamine mononitrate, copper sulfate, riboflavin supplement, Vitamin B-12 supplement, pyridoxine hydrochloride, garlic oil, folic acid, Vitamin D-3 supplement, calcium iodate, biotin, menadione sodium bisulfite complex (source of Vitamin K activity), sodium selenite.

Since she is still itching with the Purina One and it has no chicken, maybe it's the corn, at least it's a common denominator.
Now we head back to the Pet Store and start reading dogfood labels.