Hi hwballew –
If you go to the review section of DFA and read the reviews for Purina and Iams you’ll see that they are all very low quality foods. Dry food is definitely more convenient, but a balanced home prepared food is the healthiest. By type – from worst to best: kibble < canned < dehydrated < commercially prepared fresh food < balanced home cooked < commercial raw < balanced homemade raw (granted the foods are rated the same). If you want to stick with kibble for convenience reasons, I'd recommend picking out 2 or 3 (or more) 4 or 5 star dry foods and rotating – top the dry food with a quality canned food, raw food or healthy "people" food (eggs, tinned sardines, leftover lean cuts of meat, etc.). Canned foods, dehydrated foods and commercially prepared cooked and raw foods would be a step up from kibble and wouldn't require the time and knowledge that a home-prepared diet requires. These options are more costly than dry, but if cost isn't an issue they'd be a big improvement over dry food. If you do want to home prepare her meals, research first. It's not difficult to prepare a balance diet but it does take some research. There are many great books available with recipes formulated by veterinarians and nutritionists. Dogaware.com is probably the best online resource for homemade diets. The homemade food and raw food forms here have some useful information – my dogs' menus are posted on the suggested menu thread in the raw food forum.
For digestion problems I would supplement with a high quality probiotic supplement, enzymes and a little bit of plain canned pumpkin. Remember, because she's eaten lower quality foods for so long she may experience some digestive upset when you switch foods. These supplements will help a bit – make sure to do a gradual transition.
Is she on a joint supplement? I just posted some supplement recommendations to another poster on the "Mercola Joint Supplement vs. Others" thread under the "Dog Supplements" forum.
Good luck!
