I have a 5 wk old NN. I noticed these bumps on his neck about a week ago. They look like little clear round blisters. The old bumps are now scabbing over but new bumps are showing up in other areas of the back of his neck. The area is also raised. The best way to describe it is it looks just like poison ivy. There are 9 chicks and he's the only one showing these. They are in a brooder pen in the garage on pine shavings, changed every 3-4 days, and under a heat lamp. I open the garage door in the daytime so they can sun at one end of the pen. My only thought is that he is having an allergic reaction. Any body seen this before?