I recently acquired 3 baby chicks from a local breeder: a Light Brahma, a Welsummer and a Black Copper Marans. A few days ago, my Black Copper Marans (Sophie) began panting and was having labored breathing. Sophie also appeared to be weak, would occasionally shake her head from side to side, sneeze every now and then, and didn't seem to eat or drink very much. Along with those symptoms, Sophie wouldn't move much and would sometimes chirp as she breathes. My other two chicks, Dixie and Trudy, are very healthy and doing great. The weird thing is that Sophie's symptoms are intermittent.... I've checked the temperatures in the brooder, and they're not too high (90 degrees going into their second week). They all have plenty of room to escape the heat. They have fresh water and food. I don't suspect a disease since none of the other two are sick or showing similar symptoms. I'm new to raising chicks, am I missing something?