I have two 4-month old chickens of unknown sex and breed. I believe they are mixed breeds from a little schoolyard farm in our city. Anyway, one of them has a wattle that has a scab-type thing on it. I tried to get pictures but it's not easy. Its wattles are two totally different sizes also. Here is a picture of both sides of its head. The side with the larger wattle is the side that has the crusty black scabby looking thing on the edge of it.