I recently switched my dogs to a raw diet and they are itching. Could they be allergic to chicken?

Cindy,

I recently switched my 2 GSDs (a male, 3 years old & a female, 10 months) to a raw diet. It's been 3 weeks now. I have no issues w/poop, etc. Both love it. My 3 year old's teeth are already white again! And his coat is softer & shinier. I feel pretty confident in my meal prep, but I do have a question? Have you heard of dogs being allergic to chicken? I ask, because both are scratching like crazy, especially at night. Today I remembered that when I got the male, the breeder had him on a chicken based kibble. As a puppy he scratched & scratched (there's definitely no fleas), around 1 year old, I switched him to a bison based kibble & the itching/scratching went away. The female started on the bison so never had a scratching issue. Now that I'm feeding raw, and these past 3 weeks primarily chicken (just started to add pork to it) they both are itching?? If so, I don't think I can afford to feed raw. Where I live, Southern CA, there are no butchers & no hunters... unlike WI.

Thanks