Thanks Rannmiller.
In answer to your question, I started her out as a puppy on Science Diet's large breed puppy food. This of course was before I knew anything about dog food and was under the mistaken belief that Science Diet was one of the best out there. At that time, I noticed that she kept biting along her flanks, hindquarters, and legs. I checked with the vet, and he could find no skin problems, although his wife, also a vet (they have a veterinary partnership), said it would bear watching, as it might be allergies.
So when Lily turned a year old, I decided to wean her from the puppy food, and in discussing matters with our Mrs. Vet, she thought it might be a good time to try a lamb and rice diet, and advised me that I needed to make certain that the food was truely lamb and rice; no corn, wheat, beef, eggs, etc. At that point I found Nature's Recipe Lamb & Rice and started Lily on it. I noticed that she did very well on it -- no biting, itching, etc., and as an added benefit, better stools and no flatulence.
However, it was about that time that I also started doing research on dog foods, and discovered this site and dogfoodanalysis.com. In doing so, I saw that Nature's Recipe was criticized for having low meat content, beet pulp (if I remember correctly) and the synthetic vitamin k that everyone says causes long term problems. And of course I started seeing other, better brands, including Innova Adult Large Breed, which our local pet store carries.
This looked like (and I think still is) a very good dog food. I started Lily out on it, and after about two weeks noticed that while her stools were very good, she was excessively shedding and actually losing hair, particularly on her chest and belly. I live in central Illinois and it was extremely hot at the time, so I thought she was just shedding some because of the heat.
However, the shedding continued, particularly on her underside, to the point where I was starting to see bare skin, and it was spreading to her lower sides, where again, sadly, you could see bare skin. So, we went back to the vet and had her tested for thyroid problems. Those tests came back negative, and the Mr. Vet asked me about any changes in her food or environment. I told him about the food, and he asked that we allow him to look over the ingredients. I gave him a copy of the Innova ingredients (chicken, turkey, rice), and he thought it was a very low allergenic food. He prescribed an antihistamine and skin supplement.
Nonetheless, her shedding and hair loss continued, and when I most recently spoke to Mrs. Vet, she wanted me to go back to a lamb and rice diet. She said that one of her personal dogs had the same problem that only was corrected with a dietary change. She said that while it is unusual, given the history she thought Lily could be allergic to chicken or turkey, or a fowl type bird, and that the symptoms could be more severe now because there was a higher concentration of these meats in the Innova rather than the Science Diet.
So, that's where I am. The antihistamines have helped, as Lily is no longer scratching and biting, but I don't want to keep her on those forever. And, we need to get her off those so that we can do allergy testing.
Sorry this has been so long-winded. If you or anyone has any other thoughts on the hair loss or dog food I would sure appreciate hearing them.
Tom