I noticed my three and a half month old rooster was getting picked on these past couple of days and was slightly underweight. I thought the weight was due to the stress of getting picked on but then on the 30th of November I found him in the corner and when I encouraged him to walk he was unbalanced and kept leaning backwards. I isolated him and hand fed him food and water all day. By the afternoon his condition had deteriorated to the point where he could not stand up at all without completely falling either on his side or back. Both legs were still kicking as he lay on his side so they weren't paralysed (I think). The vets were all booked for that day so I hoped he would last the night. Come morning he looked awful, he had his eyes closed and was gasping for breath. His comb was also slightly blue, I'm assuming because not enough oxygen was in his system. As he was in so much pain I decided to put him down that morning. I have no clue what happened to him as so far the other chickens appear normal. I did worm all my chickens on the 29 of November, one day before he showed real signs of being sick. I would greatly appreciate any ideas anyone has regarding what caused his death. He was such a beautiful and gentle rooster, I just want to know why he died so it never happens again in my flock as no animal should endure what he went though. Thank you, Erin.