My mini doxie is overweight,lethargic, and has really bad skin allergies. I have tried EXPENSIVE dog food from the vet, yogurt, local honey, malesab shampoo,predisone….nothing works. I want to try to make her food from natural ingredients. Any ideas?

I have two dogs that I am considering feeding a natural/fresh food diet rather than store bought dog food but have no idea how to start. I want them to get all the appropriate nutrients and need to know appropriate serving sizes. One of the boys is a 105lb. Chocolate Lab. The other is a 52lb. Lab/Saluki mix. I would really appreciate answers from vetrinarians or other dog care professional who are familiar with the nutritional needs of these breeds.