Need some help.

[BurlyGirl]

It doesn't matter if the blend is grain-free. Your dog could be allergic to half a dozen other things in the dog food (believe me I KNOW!). A simple blood test from your veterinarian can cure a lot of headache, and avoid trial and error-despite it not being 100 percent perfect, you will at least know what foods to avoid feeding your dog and can narrow down brands/blends. Even still, in the summer or throughout the year your dog may need Benadryl, prednisone, atopica, and a med I cannot for the life of me remember now. Discuss with your vet.

Our old girl had chronic problems with her ears, and as it turned out, we needed to go grain-free. We switched her to the Wild Prairie formula and she did well, ears cleared up and she stopped chewing her itchy feet. As you say, though, the OP's problem may be more complex than ours was.

[Farmin n huntin]

I had this problem to, i solved it by not feeding him human food no treats and only one kind of dog food with no switches. Also try and keep him as dry as possible

[Sharon]

Very good point not mentioned before - keep the dog dry. Dry out those ears etc. well after every time in the fields etc.

(Welcome to the dog forum. )