Our BPR had labored breathing and wheezing. Her comb and waddles were turning from red to purple. Clearly she wasn't getting enough oxygen but I didn't know what caused it. I called the vet and he said to bring her in for a shot. He said it looked like she was having an allergic reaction and he gave her medication for the reaction. We put her in the house in a large kennel with a roost. Three hours later (right now) her labored breathing has stopped and she is roosted for the night. Okay, what caused the reaction? None of the other chickens are showing symptoms of allergy and they all eat the same food. My wife gave them scraps today and I blamed her cooking but the chickens love green beans and collards. I don't get it.