To start, I want to say we are new to keeping chicken. Someone gave us a couple of chickens, they are around 10 weeks old. They are very smelly, and seem to have trouble breathing. Here is a video: https://drive.google.com/open?id=0B2z2vC98qDWLOXZ2Q256YVBqbnM Do you know what is wrong with them? Thanks in advanced!