My dog has been itching and scratching a lot lately, along with having recurring ear infections and maybe even some hair loss. I suspect they might have food allergies. What are some good brands of hypoallergenic dog food to start with? I'm looking for a food that uses limited ingredients and a novel protein source, like kangaroo or salmon, that my dog likely hasn't been exposed to before. Are there any brands that you've had success with that also meet these criteria?