So I am going to go ahead and disagree with everyone lol. You want a definite answer as to whether you're dealing with food allergies? Try out Medi-Cal Anallergenic. Yes, it's a vet diet, and yes, it's expensive as hell. That being said, it'll give you your answer as to whether this is a symptom of a food based allergy.
You can continue trying out different foods, but each attempt requires 3-6 weeks to see any significant change. If there is no change then you're off to the pet store to pick up something new, and go through the process of slow introduction all over again.
Have you bathed your pups? Perhaps it was an allergy to a shampoo used.
It could be from excessive moisture as well. Try drying them off when they come in from outside if its wet, see if that changes anything.
Side Note to Members~ We should be careful when bashing Vet Diets. I agree that some of the diets are comparable to pet store foods, the Development line included. However, most of the prescription diets are specially formulated to help in the management of many diseases. Making generalized statements about vet diets being garbage, imo, is irresponsible.
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