I hatched out a d'Uccle chick that has a weird round thing attached to its bottom. I don't know what it is and the chick seems to be acting fine. He/she is still in the incubator because I'm afraid that if I put it in the brooder the other chicks will try to peck at it. This hatch didn't do so well I had 6 eggs not hatch (these were not shipped eggs) and it looks like they all died in the shell all around the same time in lock down.Humidity and temperature were fine. Five of the eggs were d'Uccle eggs. The blob on the chick doesn't feel like its filled with anything. I pressed on it and it went down and then came back up like it has air inside of it.