Thank you

It isn't for my dog. I am asking on behalf of someone else in another forum from another country

He is feeding Royal Canin to his dog and his dog is licking his paw raw. Vet ruled out fungus and such after tests are done. I just told him that the culprit is Royal Canin, the corn in it but I was't sure if food allergy can only show up later on in life as he has been feeding his dog Royal Canin for the longest time-years so I come on YT to ask

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