IMHO - Switching to a high quality dog food could help this problem. Neither of the foods you have your dog on is what I would consider high quality. You can read this article and the one at the bottom more indepth if you want by going to the website. Dogs are no different than human's in that we smell like what we eat and our health is determined by what we eat. Both of these dog foods main ingredient is corn which will cause itching and dry skin. 2 food that are better and that are avilable in Petsmart/Petco are Natural Balance and Nutro. It will take a while if you switch foods before this will clean up your problem (same as if you are a human) but it will help. A good oatmeal shampoo will help in the mean time along with a vet/groomer visit to make sure the anal glands are emptied. Good Luck.
IMPORTANT INFORMATION ABOUT DOG FOOD
http://www.5stardog.com/dog-food.asp
People across the globe are striving to improve their health - through exercise and proper nutrition. Every day we make informed decisions about the foods we eat. Companies have recognized this trend and have begun marketing low-fat, low-calorie, or low-carb versions of our favorite foods. But with all of this attention to our own health, we may be forgetting the nutrition of our loyal companion pets. Sure, pet food companies have created special formulas for overweight, older, or active dogs; but even these blends do not meet the necessary requirements for your pet's health. In fact, studies have shown that your dog's food may cause illnesses such as skin allergies, stomach problems, heart disease, diabetes, and cancer.
A BUSINESS FIRST PHILOSOPHY
Pet food companies are run in the interest of business first, while disregarding the interests of those who consume their products - your pet.
Pet food is produced and marketed with the owner - not the pet - in mind. Cute shapes, different colors, exotic flavors-these are characteristics that people have come to expect in their food. Think about colored ketchup, the staggering array of flavor choices for potato chips, and even pasta shaped like cartoon characters. Pepperidge Farm Goldfish(r) crackers, as an example, are shaped like fishs, complete with eye and smiling mouth. You can buy the regular cheddar ones or get the colored ones that come in purple, red orange, and green. The flavor-blasted crackers come in cheddar, nacho, BBQ, and even a flavor called "Xplosive Pizza."
Kids love foods with different shapes, colors, and flavors. But what about your dog? The only characteristic that your dog is seeking in food is taste. Colored and shaped morsels are for your benefit, not your dog's.
The whole point of marketing is to convince the consumer to purchase one product among a sea of similar products. Yet the image depicted by a company for their product is not always accurate. We are led to believe that our dogs are eating moist whole chicken, choice cuts of beef, fresh-picked grains, even chunks of real vegetables. Unfortunately, this is just an image
.
The pet food industry only uses ingredients that are unfit for human consumption. They make a profit from waste that would otherwise be worthless to them. Pet food companies owned by multinational companies include:
* Nestlé - Alpo, Come 'N Get It, Mighty Dog, Chef's Blend, Fancy Feast, Friskies, Kit 'N Kaboodle, Deli-Cat, and Nestlé Purina products such as Dog Chow, Pro Plan, Beneful and Purina One
* Colgate-Palmolive -
Hill's Science Diet Pet Food
* Del Monte - 9-Lives, Kibbles `n Bits, Cycle, Gravy Train, Nature's Recipe, and Reward
* Procter & Gamble -
Eukanuba and Iams
* Mars - Pedigree, Advance, Cesar, Whiskas and Sheba
Another leading pet food, Nutro, is not a multinational company.*
Multinational companies who own dog food manufacturing companies are in the perfect relationship as far as business is concerned. According to the Animal Protection Institute, the benefits of being a multinational company include:
1. Greater buying power
2. Existing customer base
3. Readily available funds
4. Accessibility to cheap ingredients
Here is another article
http://www.api4animals.org/facts?p=359&more=1