LOL don't just switch him back. That's silly to say. Raw is perfectly fine for him. The key is to add one item at a time gradually, thereby being able to note anything that suddnely seems to cause a problem and thus removing that from the diet. It's not difficult and it could be completely unrelated. Start with one item, feed for a few days, it also helps get the system used to raw. Then you can add another. The dog will be perfectly fine while adding new items slowly to avoid upset tummies or allergy problems. It could also be purely coincidental. Don't ask the board, talk to your vet.